Articles de revues : « Immunité hybride »

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Crotty, Shane. « Hybrid immunity ». Science 372, n^o 6549 (24 juin 2021) : 1392–93. http://dx.doi.org/10.1126/science.abj2258.

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Shi, Meiqing, Liping Su, Sigou Hao, Xulin Guo et Jim Xiang. « Fusion Hybrid of Dendritic Cells and Engineered Tumor Cells Expressing Interleukin-12 Induces Type 1 Immune Responses against Tumor ». Tumori Journal 91, n^o 6 (novembre 2005) : 531–38. http://dx.doi.org/10.1177/030089160509100614.

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Aims and Background Dendritic cell (DC)-tumor fusion hybrid vaccinees that facilitate antigen presentation represent a novel powerful strategy in cancer immunotherapy. Preclinical studies have demonstrated that IL-12 promotes specific antitumor immunity mediated by T cells in several types of tumors. In the present study, we investigated the antitumor immunity derived from vaccination of fusion hybrids between DCs and engineered J558/IL-12 myeloma cells secreting Th1 cytokine IL-12. Methods The expression vector pcDNA-IL-12 was generated and transfected into J558 myeloma cells and then bone marrow-derived DCs were fused with engineered J558/IL-12 cells. The antitumor immunity derived from vaccination of the fusion hybrid DC/J558/IL-12 was evaluated in vitro and in vivo. Results DC/J558/IL-12 cells secreted recombinant IL-12 (1.6 ng/mL), and inoculation of BALB/c mice with DC/J558/IL-12 hybrid induced a Th1 dominant immune response and resulted in tumor regression. Immunization of mice with engineered DC/J558/IL-12 hybrid elicited stronger J558 tumor-specific cytotoxic T lymphocyte (CTL) responses in vitro as well as more potent protective immunity against J558 tumor challenge in vivo than immunization with the mixture of DCs and J558/IL-12, J558/IL-12 and J558, respectively. Furthermore, the antitumor immunity mediated by DC/J558/1L-12 tumor cell vaccination in vivo appeared to be dependent on CD8+ CTL. Conclusions These results demonstrate that the engineered fusion hybrid vaccines that combine Th1 cytokine gene-modified tumor cells with DCs may be an attractive strategy for cancer immunotherapy.

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Dang Caihong, 党彩虹, et 聂敏 Nie Min. « 基于免疫和模拟退火混合算法的量子卫星资源调度策略 ». Laser & ; Optoelectronics Progress 61, n^o 21 (2024) : 2127004. http://dx.doi.org/10.3788/lop240585.

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Xiao, Wei, Binglin Chen, Jun Wang, Zhiying Zou, Chenghui Wang, Dayu Li, Jinglin Zhu, Jie Yu et Hong Yang. « Integration of mRNA and miRNA Profiling Reveals Heterosis in Oreochromis niloticus × O. aureus Hybrid Tilapia ». Animals 12, n^o 5 (3 mars 2022) : 640. http://dx.doi.org/10.3390/ani12050640.

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Heterosis is a widespread biological phenomenon in fishes, in which hybrids have superior traits to parents. However, the underlying molecular basis for heterosis remains uncertain. Heterosis in growth and survival rates is apparent in hybrid tilapia (Oreochromis niloticus ♀ × O. aureus ♂). Comparisons of growth and hematological biochemical characteristics and mRNA and miRNA transcriptional analyses were performed in hybrid and parents tilapia stocks to investigate the underlying molecular basis for heterosis. Growth characteristics and hematological glucose and cholesterol parameters were significantly improved in hybrids. Of 3097 differentially expressed genes (DEGs) and 120 differentially expressed miRNAs (DEMs) identified among three stocks (O. niloticus, O. aureus, and hybrids), 1598 DEGs and 62 DEMs were non-additively expressed in hybrids. Both expression level dominance and overdominance patterns occurred for DEGs and DEMs, indicating that dominance and overdominance models are widespread in the transcriptional and post-transcriptional regulation of genes involved in growth, metabolism, immunity, and antioxidant capacity in hybrid tilapia. Moreover, potential negative regulation networks between DEMs and predicted target DEGs revealed that most DEGs from miRNA-mRNA pairs are up-regulated. Dominance and overdominance models in levels of transcriptome and miRNAome facilitate the integration of advantageous parental alleles into hybrids, contributing to heterosis of growth and improved survival. The present study provides new insights into molecular heterosis in hybrid tilapia, advancing our understanding of the complex mechanisms involved in this phenomenon in aquatic animals.

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Cortes, S., A. Albuquerque-Wendt, C. Maia, M. Carvalho, I. A. Lima, L. A. R. de Freitas, W. L. C. dos-Santos et L. Campino. « Elucidating in vitro and in vivo phenotypic behaviour of L. infantum/L. major natural hybrids ». Parasitology 146, n^o 5 (29 novembre 2018) : 580–87. http://dx.doi.org/10.1017/s0031182018001993.

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AbstractThe clinical manifestation and course of Leishmania infections depend on factors such as species, virulence and host-immunity. Although trypanosomatids are considered to have clonal propagation, genetic hybridization has produced successful natural hybrid lineages. Hybrids displaying strong selective advantages may have an impact on pathogenesis and the eco-epidemiology of leishmaniasis. Thus, characterization of phenotypic properties of Leishmania hybrids could bring significant insight into the biology, infectivity, pathogenicity and transmission dynamics of these atypical strains. The present study focuses on phenotypic features and survival capacity of Leishmania infantum/Leishmania major hybrid isolates as compared with representative putative parental species, L. infantum and L. major. In vitro assays (growth kinetics, susceptibility to different conditions) and in vivo infection (parasite detection and histopathological alterations) showed that hybrids present higher growth capacity and decreased susceptibility to reactive oxygen species. Furthermore, evaluation of infected spleen tissue suggests that hybrids induce a stronger immune reaction than their putative parents, leading to the development of white pulp hyperplasia in B-lymphocyte compartments. Overall, these hybrids have shown high plasticity in terms of their general behaviour within the different phenotypic parameters, suggesting that they might have acquired genetic features conferring different mechanisms to evade host cells.

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Liu, Zihui, Binglin Chen, Zhiying Zou, Dayu Li, Jinglin Zhu, Jie Yu, Wei Xiao et Hong Yang. « Non-Additive and Asymmetric Allelic Expression of p38 mapk in Hybrid Tilapia (Oreochromis niloticus ♀ × O. aureus ♂) ». Animals 14, n^o 2 (15 janvier 2024) : 266. http://dx.doi.org/10.3390/ani14020266.

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Hybridization is a widely used breeding technique in fish species that enhances desirable traits in cultured species through heterosis. However, the mechanism by which hybrids alter gene expression to form heterosis remains unclear. In this study, a group of hybrid tilapia was used to elucidate heterosis through interspecies crossing. Specifically, p38 was analyzed to describe the regulation of gene expression variation in hybrid tilapia. Transcripts from the Nile tilapia allele were found to be significantly higher than those from the blue tilapia allele in hybrid individuals, indicating that the expression of p38 was dominated by Nile tilapia sub-genomic alleles. The study also found a compensatory interaction of cis- and trans-acting elements of the Nile tilapia and blue tilapia sub-genomes, inducing a non-additive expression of p38 in hybrids. Eight specific SNPs were identified in the p38 promoter regions of Nile tilapia and blue tilapia, and were found to be promoter differences leading to differences in gene expression efficiencies between parental alleles using a dual-luciferase reporter system. This study provides insights into the non-additive expression patterns of key functional genes in fish hybrids related to growth and immunity response.

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Groszmann, Michael, Rebeca Gonzalez-Bayon, Rebecca L. Lyons, Ian K. Greaves, Kemal Kazan, W. James Peacock et Elizabeth S. Dennis. « Hormone-regulated defense and stress response networks contribute to heterosis in Arabidopsis F1 hybrids ». Proceedings of the National Academy of Sciences 112, n^o 46 (2 novembre 2015) : E6397—E6406. http://dx.doi.org/10.1073/pnas.1519926112.

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Plant hybrids are extensively used in agriculture to deliver increases in yields, yet the molecular basis of their superior performance (heterosis) is not well understood. Our transcriptome analysis of a number of Arabidopsis F1 hybrids identified changes to defense and stress response gene expression consistent with a reduction in basal defense levels. Given the reported antagonism between plant immunity and growth, we suggest that these altered patterns of expression contribute to the greater growth of the hybrids. The altered patterns of expression in the hybrids indicate decreases to the salicylic acid (SA) biosynthesis pathway and increases in the auxin [indole-3-acetic acid (IAA)] biosynthesis pathway. SA and IAA are hormones known to control stress and defense responses as well as plant growth. We found that IAA-targeted gene activity is frequently increased in hybrids, correlating with a common heterotic phenotype of greater leaf cell numbers. Reduced SA concentration and target gene responses occur in the larger hybrids and promote increased leaf cell size. We demonstrated the importance of SA action to the hybrid phenotype by manipulating endogenous SA concentrations. Increasing SA diminished heterosis in SA-reduced hybrids, whereas decreasing SA promoted growth in some hybrids and phenocopied aspects of hybrid vigor in parental lines. Pseudomonas syringae infection of hybrids demonstrated that the reductions in basal defense gene activity in these hybrids does not necessarily compromise their ability to mount a defense response comparable to the parents.

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Accotto, Gian Paolo, Giuseppe Nervo, Nazzareno Acciarri, Luciana Tavella, Manuela Vecchiati, Massimo Schiavi, Giovanna Mason et Anna Maria Vaira. « Field Evaluation of Tomato Hybrids Engineered with Tomato spotted wilt virus Sequences for Virus Resistance, Agronomic Performance, and Pollen-Mediated Transgene Flow ». Phytopathology® 95, n^o 7 (juillet 2005) : 800–807. http://dx.doi.org/10.1094/phyto-95-0800.

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Tomato hybrids obtained from homozygous progeny of line 30-4, engineered for Tomato spotted wilt virus (TSWV) resistance, were tested under field conditions in two locations with their corresponding nontransgenic hybrids. No transgenic hybrid became infected, but 33 to 50% of plants of each nontransgenic hybrid became infected with a severe reduction of marketable fruit production. The transgenic hybrids conformed to the standard agronomic characteristics of the corresponding nontransgenic ones. Fruit were collected from the nontransgenic plots included in the experimental field and from border rows, and seed were used to estimate the flow of the transgene via pollen. No transgene flow was detected in the protected crops; however, in the open field experiment, 0.32% of tomato seedlings were found to contain the genetic modification. Immunity to TSWV infection in 30-4 hybrids was confirmed in laboratory conditions using mechanical inoculation and grafting. Thrips inoculation in leaf discs of line 30-4 demonstrated that TSWV replication was inhibited at the primary infection site but not in leaf discs of a commercial hybrid containing the naturally occurring resistance gene Sw-5. Due to the high economic value of tomato crops worldwide and the importance of TSWV, the engineered resistance described here is of practical value for breeding into cultivars of commercial interest, because it could be combined with naturally occurring resistance, thus greatly reducing the ability of the virus to develop resistance-breaking strains.

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Tang, Jinyi, Arka Chaudhuri, Panke Qu, Yue Wu, Kristin Wavell, Marthajoy Spano, Justin Taylor, Shan-lu Liu, William Teague et Jie Sun. « Respiratory mucosal immunity against SARS-CoV-2 after vaccination and infection ». Journal of Immunology 212, n^o 1_Supplement (1 mai 2024) : 1559_5071. http://dx.doi.org/10.4049/jimmunol.212.supp.1559.5071.

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Abstract The current COVID-19 mRNA vaccine is effective in systemic immune memory but lacks in generating mucosal anti-SARS-CoV-2 immunity. While prior SARS-CoV-2 infection establishes respiratory immunity, its strain-specific nature and limited duration pose challenges for sustained protection. Recent research has shown that hybrid immunity, a combination of vaccination and infection, results in a more robust, durable, and broadly reactive immune response in circulation compared to vaccination or infection alone. However, the characteristics and protective mechanisms of hybrid immunity in the respiratory mucosa are not fully understood. Moreover, it remains to be determined whether mucosal booster vaccines could potentially induce responses that are even stronger and more broadly reactive than hybrid immunity. Here, we collect nasal wash, bronchoalveolar lavage, and blood from controls, vaccinee, convalescents, or hybrid individuals. We found that hybrid individuals displayed higher levels of specific Ab, nAb, and B cells than other groups in the respiratory mucosa. In our mouse models, although hybrid immunity showed significant mucosal humoral and cellular immune responses, an adenovirus-based mucosal vaccine booster induced more robust protective respiratory immunity against SARS-CoV-2 variants. Our findings reveal the mechanisms of protection of hybrid immunity and underscore the importance of developing mucosal vaccine boosters that can emulate heightened mucosal immunity.

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Lukomets, V. M., M. V. Trunovа et Ya N. Demurin. « Modern trends in breeding and genetic improvement of sunflower varieties and hybrids at VNIIMK ». Vavilov Journal of Genetics and Breeding 25, n^o 4 (10 juillet 2021) : 388–93. http://dx.doi.org/10.18699/vj21.042.

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Modern sunflower breeding is significantly diversified due to the different needs of agricultural production. The breeding of sunflower varieties and hybrids is carried out at V.S. Pustovoit All-Russian Research Institute of Oil Crops (VNIIMK) in all areas in demand on the market and is based on fundamental biological research. In the field of breeding for faster maturing, the following commercial cultivars were obtained: very early maturing, cv. Skormas and the three-way hybrid Achilles, early maturing cvs. Varyag and Uspekh, medium maturing cvs. Amelie, Aris and Aurus. Within the framework of breeding for immunity, eight hybrids and one variety have been produced. So at the Don experimental station (Rostov region), productive hybrids were bred, resistant to the virulent broomrape of the G race due to the presence of the Or7 gene: ‘Gorstar’, ‘Gorfild’, ‘Grant’, ‘Status’, ‘Fogor’ and the three-way hybrid Nika. On the central experimental base, the following were obtained: the mid-early hybrid Typhoon and the earlymaturing variety Platonych with resistance to common races of downy mildew and a high oil content of achenes (up to 53 %) as well as the mid-early hybrid Tayzar, which is simultaneously resistant to virulent races of broomrape and to the causative agent of downy mildew. The early maturing large-fruited sunflower variety Belochka was included in the“Russian State Register of Selection Achievements…”, and the large-fruited varieties Karavan, Konditer and Kalibr are currently undergoing state tests. The breeding use of germplasm with genes for herbicide resistance wasaccompanied by their extensive genetic study. A practical recommendation for all three alleles of the ALS gene (Imr, CLHA-Plus, Sur) was the need to create homozygous hybrids for their reliable use in appropriate production systems. For Clearfield technology, the hybrids Imidzh, Arimi and Immi have been developed; for Clearfield Plus, the hybrid Klip; and for Express Sun (or SUMO), the hybrid Surus. Klip and Surus are mid-oleic. All newly developed fertile ornamental sunflower varieties – Aurelia, Fizalia, Zhemchuzhny, Rumyanets, Agat and Mazhor – were transferred for practical use to a sterile CMS RIG basis. Thus, new achievements have been attained across the entire spectrum of modern trends in sunflower breeding.

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E. A. Imelbaeva, E. A., A. Zh Gilmanov et L. M. Saptarova. « Results of assessing herd immunity to SARS-CoV-2 in medical workers ». Terapevt (General Physician), n^o 10 (27 octobre 2023) : 6–11. http://dx.doi.org/10.33920/med-12-2310-01.

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article presents the results of a study of the level of antibodies to SARSCoV- 2 in the blood of 54 medical workers: those who were ill or vaccinated within six months before the start of the study (70.4 %), non-ill and unvaccinated (20.7 %), and those with hybrid immunit y (recovered from the disease and vaccinated) (6.9 %). The data obtained indicate a decrease in the level of herd immunity within six months, which is especially pronounced in non-immunized individuals. The presence of antibodies in low titers in non-ill and non-immunized individuals may indicate natural immunization in the context of the infection pandemic, which decreases sharply as the epidemic subsides.

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Abel, Craig A., et Melanie C. Pollan. « Field Resistance of Bacillus thuringiensis Berliner Transformed Maize to Fall Armyworm (Lepidoptera : Noctuidae) and Southwestern Corn Borer (Lepidoptera : Crambidae) Leaf Feeding ». Journal of Entomological Science 39, n^o 3 (1 juillet 2004) : 325–36. http://dx.doi.org/10.18474/0749-8004-39.3.325.

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The fall armyworm, Spodoptera frugiperda (J. E. Smith), and the southwestern corn borer, Diatraea grandiosella (Dyar), can cause economic damage to maize, Zea mays L., grown in the southeastern United States. Maize hybrids are commercially available that have been transformed to express insecticidal crystalline proteins from Bacillus thuringiensis (Bt) Berliner. The field efficacy of seven Bt hybrids were tested for control of leaf-feeding fall armyworm and southwestern corn borer. All Bt hybrids performed better than their conventional near-isolines for control of both insects. In general, the Bt hybrids provided intermediate resistance to the fall armyworm and near immunity to the southwestern corn borer. Based on larval establishment and weights, the fall armyworm was more tolerant of the insecticidal proteins expressed by the Bt hybrids than the southwestern corn borer. There was no difference in expression of insecticidal proteins among the Bt hybrids. Bt hybrids should be advantageous for the production of maize in areas that are affected by southwestern corn borer. The moderate level of resistance in the Bt hybrids to fall armyworm should be further examined to determine if amplifying the expression of insecticidal proteins or integrating other control methods along with the use of current Bt hybrid maize is needed to protect the crop from yield reduction by this pest.

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JOLY, P., V. GUESDON, E. FROMONT, S. PLENET, O. GROLET, J. F. GUEGAN, S. HURTREZ-BOUSSES, F. THOMAS et F. RENAUD. « Heterozygosity and parasite intensity : lung parasites in the water frog hybridization complex ». Parasitology 135, n^o 1 (2 octobre 2007) : 95–104. http://dx.doi.org/10.1017/s0031182007003599.

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SUMMARYIn hybridogenetic systems, hybrid individuals are fully heterozygous because one of the parental genomes is discarded from the germinal line before meiosis. Such systems offer the opportunity to investigate the influence of heterozygosity on susceptibility to parasites. We studied the intensity of lung parasites (the roundwormRhabdias bufomisand the flukeHaplometra cylindracea) in 3 populations of water frogs of theRana lessonae-esculentacomplex in eastern France. In these mixed populations, hybrid frogs (R. esculenta) outnumbered parental ones (R. lessonae). Despite variation in parasite intensity and demographic variability among populations, the relationship between host age and intensity of parasitism suggests a higher susceptibility in parentals than in hybrids. Mortality is probably enhanced by lung parasites in parental frogs. On the other hand, while parental frogs harboured higher numbers ofH. cylindraceathan hybrid frogs, the latter had higher numbers ofR. bufonis. Despite such discrepancies, these results support the hybrid resistance hypothesis, although other factors, such as differences in body size, age-related immunity, differential exposure risks and hemiclonal selection, could also contribute to the observed patterns of infection.

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Kanokudom, Sitthichai, Jira Chansaenroj, Suvichada Assawakosri, Nungruthai Suntronwong, Ritthideach Yorsaeng, Lakkhana Wongsrisang, Ratchadawan Aeemjinda et al. « Real-World Study : Hybrid Immunity against SARS-CoV-2 Influences the Antibody Levels and Persistency Lasting More than One Year ». Vaccines 11, n^o 11 (7 novembre 2023) : 1693. http://dx.doi.org/10.3390/vaccines11111693.

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This study investigated the impact of hybrid immunity on antibody responses in the participants who received two to seven doses of the COVID-19 vaccine. The study was conducted between April and June 2023. Out of 771 serum samples analyzed, 71.7% exhibited hybrid immunity (positive for total anti-N Ig), while 28.3% showed vaccine-induced immunity (negative for total anti-N Ig). Participants were categorized based on the number of vaccine doses: 2, 3, 4, and ≥5. The findings highlight a trend where a higher number of vaccine doses received was associated with a lower infection rate. There was no significant difference in total RBD Ig levels between those who received 3, 4, or ≥5 doses in both the hybrid immunity and vaccination alone groups across all observed durations as follows: <6 months, 6 to <9 months, 9 to <12 months, and ≥12 months. Hybrid immunity consistently maintained higher total RBD Ig levels and durability compared to vaccination alone, with estimated half-lives (T1/2) of 189.5 days versus 106.8 days for vaccine alone. This investigation underscored the potential benefit of hybrid immunity and raised questions about the optimal strategies for further vaccine dosing.

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Paul B. Ekpo, Ekerette E. Ekerette, et Owoidihe M. Etukudo. « Enhanced Growth, Haematological and Biochemical Performance in Hybrid Catfish of Clarias gariepinus x Clarias cavernicola ». Sumerianz Journal of Scientific Research, n^o 74 (6 décembre 2024) : 57–65. https://doi.org/10.47752/sjsr.74.57.65.

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This study evaluated the growth performance, haematological indices, and biochemical parameters of four catfish breeds, including two purebreds (Clarias cavernicola and Clarias gariepinus) and two hybrids (female C. cavernicola x male C. gariepinus and female C. gariepinus x male C. cavernicola). Over four months, growth was assessed by measuring body weight, total length, and standard length. Haematological and biochemical analyses were conducted to assess the health and immune status of the different breeds. The results indicated that the hybrid of female C. cavernicola x male C. gariepinus exhibited the highest growth performance, with significant increases in body weight and length compared to the other breeds. This hybrid also demonstrated the highest white blood cell (WBC) and lymphocyte counts, suggesting a stronger immune response, which was statistically significant (p<0.05) compared to the purebreds. Granulocyte levels were consistent across all breeds, while red blood cell (RBC) and platelet counts showed no significant differences, indicating stability in these parameters. Biochemical analysis revealed that the female C. cavernicola x male C. gariepinus hybrid had the highest total protein and globulin levels, which are indicative of better health and immune function. Albumin levels were higher in both hybrids compared to the purebreds, while cholesterol, creatinine, and glucose levels were similar across all breeds. The alleles associated with better immunity are likely present in the maternal line of C. cavernicola, leading to the superior vigour observed in the C. cavernicola (female) x C. gariepinus (male) hybrid. This enhanced vigour results in improved growth, hematological, and biochemical profiles. Compared to purebred breeds, this hybrid demonstrates better health, increased disease resistance, and a higher potential for productivity in aquaculture.

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Hablak, S. G., Ya A. Abdullaeva, L. O. Ryabovol et Ya S. Ryabovol. « Susceptibility of siberian hybrids new races of zarazhi ». Faktori eksperimental'noi evolucii organizmiv 23 (9 septembre 2018) : 154–59. http://dx.doi.org/10.7124/feeo.v23.1006.

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Aim. A study of the racial composition of broomrape on sunflower crops in the northern part of the Steppe of Ukraine. Methods. Assessment of the resistance of hybrids and sunflower test lines to broomrape was carried out by a modified soil method. Results. The broomrape parasitizing on the fields of sunflower has a high degree of virulence, which overcomes the immunity of the best hybrids of domestic and foreign breeding, resistant to the E, F and G races of this parasite. Conclusions. The emergence of new very aggressive broomrape races (E, F and G) indicates the important need to solve the problem of creating breeding material resistant to new races of this parasitic plant. Intensive with the accumulation of parasite races E, F and G in the sunflower crops is associated with the disruption of crop rotations and the saturation of fields with hybrids of this culture, resistant mainly to 4 (D) and 5 (E) races of the parasite. Keywords: Orobanche сumana Wallr., race, sunflower, hybrid, root system, root allocation, srigolactones.

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Coyne, Glare J., et Shawn A. Mehlenbacher. « 521 PB 483 RESISTANCE TO EASTERN FILBERT BLIGHT IN CORYLUS SPECIES AND INTERSPECIFIC HYBRIDS ». HortScience 29, n^o 5 (mai 1994) : 506b—506. http://dx.doi.org/10.21273/hortsci.29.5.506b.

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Eastern filbert blight (EFB) (Anisogramma anomala) is a serious disease of the European hazelnut (Coryls avellana). A single dominant gene for immunity to EFB from C. avellana `Gasaway' is being combined with good nut and kernel traits using a modified backcross approach. Additional sources of resistance would be highly desirable. Clones and seedlings of six other species (C. columa, C. comuta, C. heterophylla, C. sieboldiana, C. amencana, and C. jaquemontii] and a few interspecific hybrid selections were screened in the greenhouse to identify new sources of resistance. C. jacquemontii seedlings and C. columa clones were highly susceptible. C. comuta, C. hetemphylla, and C. sieboldiana clones were resistant, as were 86% of the C. americana seedlings tested. Five C. americana × C. avellana hybrids from New York were resistant under field conditions. One of four C. comuta × C. avellana and two of three C. hetemphylla × C. avellana hybrids were resistant.

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Sizyakina, L. P., V. Ya Zakurskaya et I. I. Andreeva. « Capacities of hybrid immunity : objective realities ». Immunologiya 45, n^o 3 (2024) : 300–311. http://dx.doi.org/10.33029/1816-2134-2024-45-3-300-311.

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Tatarnikova, V. V., V. I. Dubrovina, N. O. Kiseleva, V. A. Vishnyakov, D. D. Bryukhova, A. B. Pyatidesyatnikova, A. N. Bondaryuk et S. V. Balakhonov. « Effect of Immunity to SARS-CoV-2 Virus on Blood Cellular Composition ». Epidemiology and Vaccinal Prevention 23, n^o 2 (3 mai 2024) : 50–60. http://dx.doi.org/10.31631/2073-3046-2024-23-2-50-60.

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Relevance. The new coronavirus infection (COVID-19) is still a public health problem and a threat to socio-economic well-being. Most studies have focused predominantly on humoral immunity, and there are no data on the cellular composition of blood in dynamics. Aim. To study the dynamics of changes in blood cellular composition depending on the type of immunity formed (natural, hybrid, breakthrough, postvaccinal) to SARS-CoV-2 virus. Materials and Methods. A total of 130 volunteers participated in the study. Immunophenotyping of peripheral blood leukocytes using flow cytometry was performed. The presence of specific IgG antibodies to N-protein SARS-CoV-2, total IgA and cytokines (IL-4, IL-10, IFN-γ, TNF-α) was assessed in serum by ELISA. Results and Discussion. A statistically significant increase in BL was recorded in volunteers with hybrid immunity 1 month (14,0% (12,3–16,4%)) after vaccination compared to healthy volunteers (9,1% (6,4–10,2%), p = 0,0007) and people with primary COVID-19 infection (10,2% (8,3–12,1%), p = 0,0134). In volunteers with natural and hybrid immunity, as well as in revaccinated people, an increase in B1-cells (CD3-CD19+CD5+CD27-) was observed during 3–9 months of observation. It is shown that the increase of B-lymphocytes with «switched» class of synthesized antibodies was detected in people with breakthrough immunity. Increased levels of T-lymphocytes expressing HLA-DR were recorded in all individuals during 6–9 months of follow-up. Volunteers with breakthrough immunity showed a significant increase in the positivity index when assessing the presence of specific IgG class antibodies to the coronavirus N-protein compared with volunteers with natural and hybrid immunity. Conclusions. Vaccination promotes protective immunity sufficient for timely activation of memory T- and B-cells in breakthrough immunity and maintenance of immunologic efficacy in hybrid immunity against COVID-19. The results help to assess the strain of innate and adaptive immunity in novel coronavirus infection and to fill gaps in the understanding of immunopathogenesis in COVID-19.

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Kodera, Sachiko, Akito Takada, Essam A. Rashed et Akimasa Hirata. « Projection of COVID-19 Positive Cases Considering Hybrid Immunity : Case Study in Tokyo ». Vaccines 11, n^o 3 (13 mars 2023) : 633. http://dx.doi.org/10.3390/vaccines11030633.

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Since the emergence of COVID-19, the forecasting of new daily positive cases and deaths has been one of the essential elements in policy setting and medical resource management worldwide. An essential factor in forecasting is the modeling of susceptible populations and vaccination effectiveness (VE) at the population level. Owing to the widespread viral transmission and wide vaccination campaign coverage, it becomes challenging to model the VE in an efficient and realistic manner, while also including hybrid immunity which is acquired through full vaccination combined with infection. Here, the VE model of hybrid immunity was developed based on an in vitro study and publicly available data. Computational replication of daily positive cases demonstrates a high consistency between the replicated and observed values when considering the effect of hybrid immunity. The estimated positive cases were relatively larger than the observed value without considering hybrid immunity. Replication of the daily positive cases and its comparison would provide useful information of immunity at the population level and thus serve as useful guidance for nationwide policy setting and vaccination strategies.

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Livieratos, Achilleas, Lars Erik Schiro, Charalambos Gogos et Karolina Akinosoglou. « Durability of Adaptive Immunity in Immunocompetent and Immunocompromised Patients Across Different Respiratory Viruses : RSV, Influenza, and SARS-CoV-2 ». Vaccines 12, n^o 12 (22 décembre 2024) : 1444. https://doi.org/10.3390/vaccines12121444.

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Background/Objectives. Research on respiratory virus immunity duration post-vaccination reveals variable outcomes. This study performed a literature review to assess the efficacy and longevity of immune protection post-vaccination against SARS-CoV-2, influenza, and respiratory syncytial virus (RSV), with a focus on immunocompromised populations. Specific objectives included examining humoral and cellular immune responses and exploring the impact of booster doses and hybrid immunity on extending protection. Methods. A literature review was conducted focusing on studies published from January 2014 to November 2024. The search targeted adaptive immunity post-vaccination, natural immunity, and hybrid immunity for SARS-CoV-2, influenza, and RSV. Selection criteria emphasized human populations, adaptive immunity outcomes, and immunocompromised individuals. The PICO framework guided the analysis, culminating in a detailed review of 30 studies. Results. SARS-CoV-2 vaccines exhibited robust initial antibody responses, which waned significantly within six months, necessitating frequent boosters. Influenza and RSV vaccines similarly showed declines in immunity, though some influenza vaccines demonstrated moderate durability. Hybrid immunity, arising from combined natural infection and vaccination, provided more resilient and lasting protection than vaccination alone, especially against emerging variants. Immunocompromised individuals consistently exhibited reduced durability in adaptive immune responses across all studied viruses. Challenges include rapid viral mutations, limiting the broad protection of current vaccines. Conclusions. Immune durability varies significantly across virus types and patient populations. Frequent boosters and hybrid immunity are critical to optimizing protection, particularly for vulnerable groups. The findings underscore the need for adaptable vaccination strategies and advancements in vaccine design to counter rapidly mutating respiratory pathogens effectively.

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Bondarenko, S. V., S. V. Stankevych et A. V. Matsyura. « Major cucumber diseases and the crop immunity ». Ukrainian Journal of Ecology 11, n^o 1 (20 janvier 2021) : 46–54. http://dx.doi.org/10.15421/2021_7.

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In Ukraine, cucumber (Cucumis sativus Linneus) annually occupies about 20 % of the total area of all vegetable crops sown in the open ground or 52.6 thousand hectares. The main reason that significantly reduces the quantitative and qualitative indicators of this vegetable crop's main valuable economic traits is the high incidence of commercial crops with diseases, especially downy mildew (Pseudoperonospora cubensis (Berk and M.A. Curtis) Rostovtsev). Since 1985 in Ukraine, this cucumber disease in the open ground on nonresistant varieties has continuously had intense development, in some years the development – by the type of epiphytotic. Simultaneously, the shortage of commercial yield of this vegetable crop due to the defeat of this disease under the field conditions can reach the level of 50–80 % or more, seed loss – 25–70 %. One of the main reasons for significant losses of commercial yield and seeds of gherkin cucumber under the conditions of its cultivation in the open ground is recognized as the high susceptibility of samples to some diseases, particularly downy mildew (Pseudoperonospora cubensis (Berk. and M.A. Curtis) Rostovtsev). Unfortunately, this problem has remained relevant for Ukraine over the past few decades. So, obtaining the initial material of a gherkin cucumber with a harmonious combination in the genotypes of a complex of various valuable economic characteristics (yield, quality, resistance to diseases, chemical substances content, suitability for various types of processing) and creating a modern competitive, innovative product (variety, hybrid) on its basis remains a relevant and priority task for domestic agricultural science at present. At the same time, scientists have proved that introducing complex (integrated) systems into production, which expect the biologization of protection with its transfer to an ecological and economic basis, is recognized as the most promising today. We suggested using resistant varieties (hybrids) in such integrated systems that provide the highest economic effect.

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A, Bajaji. « Adjunctive and Transformed Immunity : Histiocytic & ; Dendritic Cell Neoplasm ». Gastroenterology & ; Hepatology International Journal 3, n^o 1 (23 mars 2022) : 1–10. http://dx.doi.org/10.23880/ghij-16000139.

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Exceptional malignancies of the lymph nodes or soft tissue comprising of < 1% of the tumour incidence are the Histiocytic and Dendritic cell neoplasm. A definitive appearance/biology/ Hematology/ histopathology / exclusive therapeutic options describe the condition. Morphology and Immune reactive appraisal may be mandated to distinguish the neoplasm. Preface: Histiocytic and Dendritic neoplasms are infrequent disorders which incriminate the accessory immune system or mesenchymal cells. Subject to the origin of the neoplasm, from the bone marrow precursors or the mesenchye, the lesions may be categorized as. i) The Histiocytic sarcoma (HS), Langerhans cell histiocytosis(LCH) and the Inter-digitizing dendritic cell sarcoma (IDCS) may commence from the bone marrow precursors and ii) The Follicular dendritic cell sarcoma (FDCS), Intermediate dendritic cell sarcoma (INDCS), Fibroblastic reticular cell tumour (FRCT) and Disseminated juvenile xanthogranuloma(DJX) may emanate from the Stromal or the mesenchymal cell. Divergent differentiation of the bone marrow precursors is a usual manifestation, though hybrid or trans-differentiating malignant lymphoid clones may also materialize in Inter-digitizing dendritic cell sarcoma (IDCS), Histolytic sarcoma (HS) and Follicular dendritic cell sarcoma (FDCS). Together, Histolytic and Dendritic cell tumors constitute < 1% of the lymph node or soft tissue neoplasm. The tumors may be misinterpreted as Non Hodgkin’s Lymphoma or adjunct Lymph-Proliferative disorders. The rare malignancies may be a challenge to discern and medicate. Debatable Histolytic and Dendritic neoplasm mandate a referral. The disorder may be ascertained by the combined analysis on Histology and Immunehistochemistry

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Duché, Denis, Aurélie Frenkian, Valérie Prima et Roland Lloubès. « Release of Immunity Protein Requires Functional Endonuclease Colicin Import Machinery ». Journal of Bacteriology 188, n^o 24 (29 septembre 2006) : 8593–600. http://dx.doi.org/10.1128/jb.00941-06.

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ABSTRACT Bacteria producing endonuclease colicins are protected against the cytotoxic activity by a small immunity protein that binds with high affinity and specificity to inactivate the endonuclease. This complex is released into the extracellular medium, and the immunity protein is jettisoned upon binding of the complex to susceptible cells. However, it is not known how and at what stage during infection the immunity protein release occurs. Here, we constructed a hybrid immunity protein composed of the enhanced green fluorescent protein (EGFP) fused to the colicin E2 immunity protein (Im2) to enhance its detection. The EGFP-Im2 protein binds the free colicin E2 with a 1:1 stoichiometry and specifically inhibits its DNase activity. The addition of this hybrid complex to susceptible cells reveals that the release of the hybrid immunity protein is a time-dependent process. This process is achieved 20 min after the addition of the complex to the cells. We showed that complex dissociation requires a functional translocon formed by the BtuB protein and one porin (either OmpF or OmpC) and a functional import machinery formed by the Tol proteins. Cell fractionation and protease susceptibility experiments indicate that the immunity protein does not cross the cell envelope during colicin import. These observations suggest that dissociation of the immunity protein occurs at the outer membrane surface and requires full translocation of the colicin E2 N-terminal domain.

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Johnsen, Line, Gunnar Fimland, Dimitris Mantzilas et Jon Nissen-Meyer. « Structure-Function Analysis of Immunity Proteins of Pediocin-Like Bacteriocins : C-Terminal Parts of Immunity Proteins Are Involved in Specific Recognition of Cognate Bacteriocins ». Applied and Environmental Microbiology 70, n^o 5 (mai 2004) : 2647–52. http://dx.doi.org/10.1128/aem.70.5.2647-2652.2004.

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ABSTRACT The immunity proteins of pediocin-like bacteriocins show a high degree of specificity with respect to the pediocin-like bacteriocin they recognize and confer immunity to. The aim of this study was to identify regions of the immunity proteins that are involved in this specific recognition. Six different hybrid immunity proteins were constructed from three different pediocin-like bacteriocin immunity proteins that have similar sequences but confer resistance to different bacteriocins. These hybrid immunity proteins were then tested for their ability to confer immunity to various pediocin-like bacteriocins. The specificities of the hybrid immunity proteins proved to be similar to those of the immunity proteins from which the C-terminal halves were derived, thus revealing that the C-terminal half of immunity proteins for pediocin-like bacteriocins contains a domain that is involved in specific recognition of the bacteriocins they confer immunity to. Moreover, the results also revealed that the effectiveness of an immunity protein is strain dependent and that its functionality thus depends in part on interplay with strain-dependent factors. To further investigate the structure-function relationship of these immunity proteins, the enterocin A and leucocin A immunity proteins (EntA-im and LeuA-im) were purified to homogeneity and structurally analyzed under various conditions by Circular dichroism (CD) spectroscopy. The results revealed that both immunity proteins are α-helical and well structured in an aqueous environment, the denaturing temperature being 78.5°C for EntA-im and 58.0°C for LeuA-im. The CD spectra also revealed that there was no further increase in the structuring or α-helical content when the immunity proteins were exposed to dodecylphosphocholine micelles or dioleoyl-l-α-phosphatidyl-dl-glycerol (DOPG) liposomes, indicating that the immunity proteins, in contrast to the bacteriocins, do not interact extensively with membranes. They may nevertheless be loosely associated with the membrane, possibly as peripheral membrane proteins, thus enabling them to interact with their cognate bacteriocin.

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Sharma, Prashant, Ji Beom Shin, Bum Chul Park, Jae-Won Lee, Sang Won Byun, Na-Yoon Jang, Yu Jin Kim, Yuri Kim, Young Keun Kim et Nam-Hyuk Cho. « Application of radially grown ZnO nanowires on poly-l-lactide microfibers complexed with a tumor antigen for cancer immunotherapy ». Nanoscale 11, n^o 10 (2019) : 4591–600. http://dx.doi.org/10.1039/c8nr08704k.

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Sobolev, Gennady Ivanovich, Vladimir Vyacheslavovich Chernyshkov et Stanislav Sergeevich Saksonov. « The assessment of field resistance to scab and winter resistance of columnar apple trees in the Samara Region ». Samara Journal of Science 9, n^o 4 (30 novembre 2020) : 153–58. http://dx.doi.org/10.17816/snv202094123.

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The research was conducted from 2006 to 2019 in the garden of Research Institute of Horticulture and Medicinal Plants Zhigulevskie Sady in the village of Malaya Tsarevshchina of Krasnoyarsk District of the Samara Region on 14 (0,432 ha), 43 (0,1 ha), 44 (0,05 ha) and 47 (6,8 ha) areas. On the 14th area, to accelerate flowering, fruiting, pollen collection and hybridization, in the springs of 2007, 2009 and 2012, parent varieties-donors of immunity were grafted to scab of domestic and foreign selection in the crown of young fruit-bearing trees of the Northern synapsis. Hybrid seeds obtained by crossing these varieties with local varieties were sown on the seedling plot (in a new plantation) and tested for scab resistance at an early age (from 2 years old). Scab-resistant hybrids were culled, and resistant hybrids were replanted in the breeding garden on the 47th area and tested for winter resistance separately after low-temperature stress in the freezer and in the field. The authors have identified columnar elites resistant to scab, which are superior in winter resistance to the local zoned coastal variety Kutuzovets, zoned variety Northern synapsis and common Antonovka. Apple trees with a columnar crown type of local selection in Research Institute of Horticulture and Medicinal Plants Zhigulevskie Sady with a high field resistance to scab, immunity, winter resistance and other varietal advantages will contribute to the improvement of orchards (amateur, farm, industrial) and import substitution of fruit products in the Samara Region of Russia.

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Bygayenko, Liudmila Alexandrovna. « WILD-GROWING SPECIES OF MINT AS CARRIERS OF GENES OF RESISTANCE TO ADVERSE ENVIRONMENTAL FACTORS ». Samara Journal of Science 4, n^o 2 (15 juin 2015) : 24–30. http://dx.doi.org/10.17816/snv20152107.

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It is shown wild-growing types of mint can be carriers of genes of frost resistance and resistance to rust which is caused by a mushroom of Puccinia menthae Pers. The method of interspecific hybridization with use of the cultivated types - Mentha piperita and Mentha canadensis L., and also wild-growing types - Mentha aquatica L., Mentha spicata L. and Mentha longifolia (L.) Nathh is perspective for creation of steady grades. Sustainability donors to a rust - M. canadensis K60 (4p) and K6 M. aquatica which in a wide range of combinations provide resistance to a rust of bulk of hybrid posterity have been revealed. Interspecific hybridization at mint at the corresponding selection of parental couples is a valuable method of creation of highly productive hybrids, steady against a rust (Puccinia menthae Pers) that has been shown.. Monogenic nature of inheritance of an immunity to Puccinia menthae Pers is confirmed and the genotype of the parental forms M. canadensis, M.aquatica, M.spicata is determined by S gene, Existence of prepotent (S) or recessive alleles (s) in homozygous (SS, SSSS, ss) or a heterozygotic state (Ss, SSss) expressiveness of this sign in hybrid posterity of F1 defines. It is established that in F1 of interspecific hybrids from crossing of an allopolyploid form of a pepper mint with frost resistance plants of M. spicata it is frost resistance sign inherited generally on intermediate type, however to 30 % of plants comes nearer on this sign to the frost-resistant parent. It indicates possibility of receiving interspecific hybrids with increased frost resistance at the specified type of crossings. For creation of hybrids with the increased frost resistance use in interspecific hybridization of the frost-resistant forms M. spicata K42, K65, the S1 and S2 lines received from self-pollination of K65 (2.8.I4, 9.37.34), and also a polyploidy of M. canadensis of K60 is perspective. The gene pool of wild-growing types and forms of mint in which the genotypes possessing genes of resistance to rust and the lowered temperatures are presented is created.

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Spreco, Armin, Örjan Dahlström, Anna Jöud, Dennis Nordvall, Cecilia Fagerström, Eva Blomqvist, Fredrik Gustafsson, Jorma Hinkula, Thomas Schön et Toomas Timpka. « Effectiveness of the BNT162b2 mRNA Vaccine Compared with Hybrid Immunity in Populations Prioritized and Non-Prioritized for COVID-19 Vaccination in 2021–2022 : A Naturalistic Case-Control Study in Sweden ». Vaccines 10, n^o 8 (7 août 2022) : 1273. http://dx.doi.org/10.3390/vaccines10081273.

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The term hybrid immunity is used to denote the immunological status of vaccinated individuals with a history of natural infection. Reports of new SARS-CoV-2 variants of concern motivate continuous rethought and renewal of COVID-19 vaccination programs. We used a naturalistic case-control study design to compare the effectiveness of the BNT162b2 mRNA vaccine to hybrid immunity 180 days post-vaccination in prioritized and non-prioritized populations vaccinated before 31 July 2021 in three Swedish counties (total population 1,760,000). Subjects with a positive SARS-CoV-2 test recorded within 6 months before vaccination (n = 36,247; 6%) were matched to vaccinated-only controls. In the prioritized population exposed to the SARS-CoV-2 Alpha and Delta variants post-vaccination, the odds ratio (OR) for breakthrough infection was 2.2 (95% CI, 1.6–2.8; p < 0.001) in the vaccinated-only group compared with the hybrid immunity group, while in the later vaccinated non-prioritized population, the OR decreased from 4.3 (95% CI, 2.2–8.6; p < 0.001) during circulation of the Delta variant to 1.9 (95% CI, 1.7–2.1; p < 0.001) with the introduction of the Omicron variant (B.1.617.2). We conclude that hybrid immunity provides gains in protection, but that the benefits are smaller for risk groups and with circulation of the Omicron variant and its sublineages.

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Roza, Des. « INCREASE OF IMMUNITY CANTIK HYBRID GROUPER JUVENILES BY LIPOPOLYSACCHARIDE (LPS) ». Jurnal Ilmu dan Teknologi Kelautan Tropis 9, n^o 1 (2 novembre 2017) : 161–72. http://dx.doi.org/10.29244/jitkt.v9i1.17927.

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Disease is one of obstacle in fish culture. Immunity of fish against disease can be increased by using immunostimulant. The purpose of this experiment to increasing immunity of cantik hybrid grouper (cross breeding of tiger grouper, Epinephelus fuscoguttatus female with marbled grouper, E. polyphekadion male) to the diseases by using immunostimulant. Treatments were LPS cell walls of V. alginolyticus and commercial LPS was also used in this study, as a-control without LPS was used saline water (0.85% NaCl). The LPS was delivered by injection intra-muscularly with concentration of 0.1 mL/fish. This experiment was design by completely randomized with 3 replicates. Results showed that LPS were effective to increase titer antibody values and survival rates of cantik hybrid grouper. The titer antibody values of fish after 90 days rearing period were 128 (LPS from V. alginolyticus), 64 (commercial LPS), and only 4 in the control fish. The survival rates at the end of experiment were 88.67 ± 3.62% (LPS from V. alginolyticus), 85.22±5.93% (commercial LPS), and only 50.13 ± 6.11% in the control fish. Relative percentage survival of fish following challenged with live V. alginolyticus were 77.46% in the received LPS from V. alginolyticus cell wall and 71.12% in the fish received commercial LPS. It is suggested that LPS effective to increase immunity of cantik hybrid grouper against bacterial infection. Keywords: cantik hybrid grouper, immunity, lipopolysaccharide, Vibrio alginolyticus

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Chavda, Vivek P., Suneetha Vuppu, Toshika Mishra et Pankti Balar. « The Emergence of Hybrid Variants of SARS-CoV-2 : Towards Hybrid Immunity ». Vaccines 11, n^o 4 (30 mars 2023) : 764. http://dx.doi.org/10.3390/vaccines11040764.

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Miles, Andrew K., Malcolm W. Smith, Nga T. Tran, Timothy A. Shuey, Megan M. Dewdney et André Drenth. « Identification of Resistance to Citrus Black Spot Using a Novel In-field Inoculation Assay ». HortScience 54, n^o 10 (octobre 2019) : 1673–81. http://dx.doi.org/10.21273/hortsci14200-19.

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Citrus black spot is an important fungal disease of citrus resulting in fruit drop and rind blemish in tropical and subtropical production areas. The disease is incited by the fungus Phyllosticta citricarpa (McAlpine) van der Aa (synonym: Guignardia citricarpa Kiely), with control currently relying on the application of fungicides. Because the presence and expression of resistance is poorly understood, we sought to develop a method for inoculating fruit in the field that gives reproducible symptoms of citrus black spot consistent with natural field infection. We subsequently validated this method by screening 49 citrus accessions and characterized their qualitative expression of citrus black spot symptoms. Challenge inoculations were undertaken with a known isolate of P. citricarpa, and control fruit were inoculated with water or the endophyte P. paracapitalensis Guarnaccia & Crous. Our results showed that all mandarin, sweet orange, lemon and papeda types were susceptible; pummelo, lime, and sour orange types expressed immunity; while various hybrids were susceptible, resistant and immune. Hybrid progeny from crosses using pummelo [Citrus maxima (Burm.) Merr.] as a parent showed preliminary evidence of segregation for citrus black spot immunity. The implications of these results to achieve genetic improvement for citrus black spot resistance in citrus breeding programs are discussed.

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Bhattacharya, Madhumita, et Taraprasad Chattopadhyay. « Interference-Immunity of the Injection-Locked Hybrid Discriminator ». IETE Journal of Research 40, n^o 2-3 (mars 1994) : 69–73. http://dx.doi.org/10.1080/03772063.1994.11437171.

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Diego, Juan García-Bernalt, Gagandeep Singh, Sonia Jangra, Kim Handrejk, Manon Laporte, Lauren A. Chang, Sara S. El Zahed et al. « Breakthrough infections by SARS-CoV-2 variants boost cross-reactive hybrid immune responses in mRNA-vaccinated Golden Syrian hamsters ». PLOS Pathogens 20, n^o 1 (10 janvier 2024) : e1011805. http://dx.doi.org/10.1371/journal.ppat.1011805.

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Hybrid immunity (vaccination + natural infection) to SARS-CoV-2 provides superior protection to re-infection. We performed immune profiling studies during breakthrough infections in mRNA-vaccinated hamsters to evaluate hybrid immunity induction. The mRNA vaccine, BNT162b2, was dosed to induce binding antibody titers against ancestral spike, but inefficient serum virus neutralization of ancestral SARS-CoV-2 or variants of concern (VoCs). Vaccination reduced morbidity and controlled lung virus titers for ancestral virus and Alpha but allowed breakthrough infections in Beta, Delta and Mu-challenged hamsters. Vaccination primed for T cell responses that were boosted by infection. Infection back-boosted neutralizing antibody responses against ancestral virus and VoCs. Hybrid immunity resulted in more cross-reactive sera, reflected by smaller antigenic cartography distances. Transcriptomics post-infection reflects both vaccination status and disease course and suggests a role for interstitial macrophages in vaccine-mediated protection. Therefore, protection by vaccination, even in the absence of high titers of neutralizing antibodies in the serum, correlates with recall of broadly reactive B- and T-cell responses.

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Darrieux, M., E. N. Miyaji, D. M. Ferreira, L. M. Lopes, A. P. Y. Lopes, B. Ren, D. E. Briles, S. K. Hollingshead et L. C. C. Leite. « Fusion Proteins Containing Family 1 and Family 2 PspA Fragments Elicit Protection against Streptococcus pneumoniae That Correlates with Antibody-Mediated Enhancement of Complement Deposition ». Infection and Immunity 75, n^o 12 (8 octobre 2007) : 5930–38. http://dx.doi.org/10.1128/iai.00940-07.

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ABSTRACT PspA is an important pneumococcal vaccine candidate that is capable of inducing protection in different animal models. Because of its structural diversity, a PspA-based vaccine should contain at least one fragment from each of the two major families (1 and 2) in order to elicit broader protection. In the present work, we have tested the potential of PspA hybrids containing fused portions of family 1 and 2 (PspA1ABC-4B and PspA1ABC-3AB) PspA fragments to induce protection against pneumococci bearing distinct PspA fragments. Sera from mice immunized with these hybrid PspA fragments were able to increase C3 deposition on pneumococci bearing PspA fragments from both families, in contrast with sera made against the PspA family 1 (PspA1ABC) and PspA family 2 (PspA3ABC) fragments, which were effective only within the same family. Although PspA hybrids were able to extend protection against pneumococcal infection with strains bearing diverse PspA fragments, the immunity elicited by family 2 was clade dependent, suggesting that PspA fragments from family 2 clades 3 and 4 should both be included in a comprehensive PspA vaccine. These results indicate that PspA fusion proteins constitute an efficient immunization strategy for future PspA-based antipneumococcal vaccines since they are able to extend protection provided by a protein derived from a single transcript.

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Kozlovskiy, Vladimir, Pavel Nikolaev, Alexander Podgorniy, Alexey Kritskiy et Luiza Shamina. « Experimental studies of a hybrid car and electric car interference immunity ». E3S Web of Conferences 221 (2020) : 01001. http://dx.doi.org/10.1051/e3sconf/202022101001.

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This article covers a hybrid car interference immunity research. A combined unit-power plant vehicle prototype (a hybrid car) of a famous Russian brand is a subject of this research. Its configuration included a motor control center in boot of a car and a standard internal combustion engine control system (ICE) with upgraded software for joint operation of two power plants.

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Kurmangaliyeva, Saulesh S., Akzhan M. Madenbayeva, Saltanat T. Urazayeva, Yerlan Sh Bazargaliyev, Khatimya I. Kudabayeva et Kairat B. Kurmangaliyev. « Comparative Analysis of Vaccine-induced Immunity and Natural Immunity in Post-COVID Patients ». West Kazakhstan Medical Journal 66, n^o 4 (20 décembre 2024) : 387–400. https://doi.org/10.18502/wkmj.v66i4.17770.

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The COVID-19 pandemic has prompted an urgent need to understand the differences between vaccine-induced and natural immunity, particularly in the context of post- COVID syndrome (long COVID). This review compares the immune responses elicited by natural infection and vaccination, focusing on their duration, strength, and effectiveness in mitigating long COVID symptoms. Vaccine-induced immunity, primarily targeting the spike protein of SARS-CoV-2, often produces a more consistent antibody and T-cell response, especially when bolstered by booster doses. In contrast, natural immunity, though broader in scope, is more variable and influenced by factors such as infection severity. Hybrid immunity, resulting from both infection and vaccination, may offer superior protection against long COVID. This comparative analysis highlights the importance of understanding these immune mechanisms to optimize protection strategies against SARS-CoV-2 and its variants.

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Guo, Wei, Yi Guo, Shun Tang, Huayi Qu et Hui Zhao. « Dendritic Cell-Ewing’s Sarcoma Cell Hybrids Enhance Antitumor Immunity ». Clinical Orthopaedics and Related Research 466, n^o 9 (19 juin 2008) : 2176–83. http://dx.doi.org/10.1007/s11999-008-0348-7.

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Rodriguez Velásquez, Sabina, Loza Estifanos Biru, Sandrine Marie Hakiza, Muaamar Al-Gobari, Isotta Triulzi, Jyoti Dalal, Camille Beatrice Gaza Varela, Sara Botero Mesa et Olivia Keiser. « Long-term levels of protection of different types of immunity against the Omicron variant : a rapid literature review ». Swiss Medical Weekly 154, n^o 5 (6 mai 2024) : 3732. http://dx.doi.org/10.57187/s.3732.

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INTRODUCTION: With the emergence of newer SARS-CoV-2 variants and their substantial effects on the levels and duration of protection against infection, an understanding of these characteristics of the protection conferred by humoral and cellular immunity can aid in the proper development and implementation of vaccine and safety guidelines. METHODS: We conducted a rapid literature review and searched five electronic databases weekly from 1 November 2021 to 30 September 2022. Studies that assessed the humoral or cellular immunity conferred by infection, vaccination or a hybrid (combination of both) in adults and risk groups (immunocompromised and older populations) were identified. Studies were eligible when they reported data on immunological assays of COVID-19 (related to vaccination and/or infection) or the effectiveness of protection (related to the effectiveness of vaccination and/or infection). RESULTS: We screened 5103 studies and included 205 studies, of which 70 provided data on the duration of protection against SARS-CoV-2 infection. The duration of protection of adaptive immunity was greatly impacted by Omicron and its subvariants: levels of protection were low by 3–6 months from exposure to infection/vaccination. Although more durable, cellular immunity also showed signs of waning by 6 months. First and second mRNA vaccine booster doses increased the levels of protection against infection and severe disease from Omicron and its subvariants but continued to demonstrate a high degree of waning over time. CONCLUSION: All humoral immunities (infection-acquired, vaccine-acquired and hybrid) waned by 3–6 months. Cellular immunity was more durable but showed signs of waning by 6 months. Hybrid immunity had the highest magnitude of protection against SARS-CoV-2 infection. Boosting may be recommended as early as 3–4 months after the last dose, especially in risk groups.

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Livieratos, Achilleas, Charalambos Gogos et Karolina Akinosoglou. « Impact of Prior COVID-19 Immunization and/or Prior Infection on Immune Responses and Clinical Outcomes ». Viruses 16, n^o 5 (26 avril 2024) : 685. http://dx.doi.org/10.3390/v16050685.

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Cellular and humoral immunity exhibit dynamic adaptation to the mutating SARS-CoV-2 virus. It is noteworthy that immune responses differ significantly, influenced by whether a patient has received vaccination or whether there is co-occurrence of naturally acquired and vaccine-induced immunity, known as hybrid immunity. The different immune reactions, conditional on vaccination status and the viral variant involved, bear implications for inflammatory responses, patient outcomes, pathogen transmission rates, and lingering post-COVID conditions. Considering these developments, we have performed a review of recently published literature, aiming to disentangle the intricate relationships among immunological profiles, transmission, the long-term health effects post-COVID infection poses, and the resultant clinical manifestations. This investigation is directed toward understanding the variability in the longevity and potency of cellular and humoral immune responses elicited by immunization and hybrid infection.

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Engalycheva, I. A., Е. G. Kozar et A. A. Ushakov. « Selection for immunity in FSBSI FSVC – history and modernity ». Vegetable crops of Russia, n^o 4 (9 juillet 2024) : 5–14. http://dx.doi.org/10.18619/2072-9146-2024-4-5-14.

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Relevance. Maintaining the phytosanitary condition of vegetable and melon crops is an important component in the technologies of cultivation of new and promising varieties and hybrids, since losses from diseases of various etiologies reach 30% or more. This determines the need for immunological studies of the resistance of vegetable and melon crops to phytopathogens of various etiologies, where the basis of the strategy for creating new varieties and hybrids is the joint work of a breeder and a phytopathologist. To do this, it is important to conduct an annual study of the species composition in order to identify new harmful objects that have a negative impact on the profitability of production, as well as to develop measures to protect vegetable crops from the most harmful and economically significant pests and diseases.Methodology and Results. The extensive experimental network of the Federal Scientific Vegetable Center (FSBSI FSVC) in various ecological and geographical zones allows testing varieties and hybrids of vegetable and melon crops in various soil and climatic conditions, including evaluating them for the most harmful phytopathogens in these regions. This review article briefly highlights the main stages of the history of development and current trends in phytopathological research in Russia and our center. The most significant achievements of scientists of the FSBSI FSVC are presented, aimed at a comprehensive study of the current state of populations of pathogens on vegetable and melon crops, resistance factors controlling the interaction of organisms in pathosystems, including genetic ones, optimization and development of new methodological approaches in breeding for immunity and scientific justification of recommended modern protection systems.

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De Gee, A. L., R. F. Levine et J. M. Mansfield. « Genetics of resistance to the African trypanosomes. VI. Heredity of resistance and variable surface glycoprotein-specific immune responses. » Journal of Immunology 140, n^o 1 (1 janvier 1988) : 283–88. http://dx.doi.org/10.4049/jimmunol.140.1.283.

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Abstract The question of genetic linkage of parasite-specific immune responses to resistance to infection in experimental African trypanosomiasis was addressed. For this purpose, major histocompatibility complex-compatible resistant and susceptible inbred mouse strains and their F1 hybrid, F2 hybrid, and backcross offspring were infected with Trypanosoma brucei rhodesiense LouTat 1. Immunologic control of the first peak of parasitemia and survival times were the parameters measured. As we have reported previously (R. F. Levine and J. M. Mansfield, J. Immunol. 133:1564, 1984), B10.BR/SgSnJ mice are relatively resistant and controlled the growth of the infecting variant antigenic type (VAT) by mounting an antibody response to exposed epitopes of the variable surface glycoprotein (VSG). Fluctuating parasitemias resulting from sequential growth of different variable antigenic types occurred subsequently, and these mice died with a median survival time of 48 days. C3HeB/FeJ mice, relatively susceptible, did not control the infecting VAT and did not exhibit VSG-specific antibodies. These mice died with a median survival time of 22 days. The (B10.BR X C3H)F1 hybrids derived from crosses between resistant and susceptible mice all exhibited VSG-specific antibody responses and controlled the infecting VAT population. However, the median survival time of the F1 hybrids (24 days) was not significantly different from the survival time of the susceptible C3H parent. These findings demonstrate for the first time that antibody-mediated control of parasitemia is inherited as a dominant trait; that overall resistance, as measured by survival time, is inherited as a recessive trait (e.g., susceptibility is dominant); and that the two events segregate independently of one another. Further analyses of the inheritance of immunity and resistance (survival time) were made in which the F2 hybrid and backcross studies revealed that there are multiple genes controlling the VSG-specific antibody response as well as determining susceptibility. An extension of the present studies to a similar but non-major histocompatibility complex-mouse model system of resistance and susceptibility (C57BL/6J and C3H/HeJ mice, F1 hybrids, and 11 recombinant inbred B X H strains derived from them) was made in order to link the strain distribution patterns of known genetic markers with control of VSG-specific antibody responses or with control of susceptibility. Results of this study showed that resistance varied independently of the ability to control parasitemia with VSG-specific B cell responses.(ABSTRACT TRUNCATED AT 400 WORDS)

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Russell, Rodney S. « Hybrid Immunity Against Severe Acute Respiratory Syndrome Coronavirus 2 ». Viral Immunology 35, n^o 6 (1 juillet 2022) : 391. http://dx.doi.org/10.1089/vim.2022.0116.

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Shervani, Zameer, Deepali Bhardwaj, Roma Nikhat, Aiman Ibbrahim, Sadia Hasan, Intazam Khan, Umair Yaqub Qazi et al. « Serosurvey of Haryana and Odisha : COVID-19 Hybrid Immunity ». European Journal of Medical and Health Sciences 4, n^o 2 (17 mars 2022) : 27–32. http://dx.doi.org/10.24018/ejmed.2022.4.2.1173.

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The seroprevalence in Indian states Haryana and Odisha has been investigated. The seropositivity in the Haryana population increased with time from 8% to 14.8% to 76.3% as recorded in August, October 2020, and September 2021, respectively. The virus spread was continuous as the increase in seroprevalence was monotonous. The three COVID-19 pandemic waves that hit Haryana in September, November 2020, and May 2021 infected the population and generated antibodies. The last serosurvey conducted in September 2021 which registered 76.3% seroprevalence might have a contribution from vaccination as 25% of all the population was fully vaccinated and 60% had one dose. The seroprevalence in Odisha was found to be 20.8%, 68.1%, and 73% in the surveys conducted in August 2020, June, and August 2021, respectively. The survey conducted in Odisha in August 2021 found that 93% of the healthcare workers had antibodies suggested that in the general population also, 93% seroprevalence might be possible by strong vaccination drive or repeated virus exposure. A maximum seroprevalence of 75% was found in the age group of 19-44 years and the lowest of 66% was recorded among 60-plus individuals.

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Ji, Hongshan, et Zhiguo Zhou. « A ‘Hybrid’ Radiotherapy Regimen Designed for Immunomodulation : Combining High-Dose Radiotherapy with Low-Dose Radiotherapy ». Cancers 14, n^o 14 (19 juillet 2022) : 3505. http://dx.doi.org/10.3390/cancers14143505.

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Radiotherapy (RT) affects anti-tumor immunity. However, the exact impact of RT on anti-tumor immune response differs among cancer types, RT dose and fractions, patients’ innate immunity, and many other factors. There are conflicting findings on the optimal radiation dose and fractions to stimulate effective anti-tumor immunity. High-dose radiotherapy (HDRT) acts in the same way as a double-edged sword in stimulating anti-tumor immunity, while low-dose radiotherapy (LDRT) seems to play a vital role in modulating the tumor immune microenvironment. Recent preclinical data suggest that a ‘hybrid’ radiotherapy regimen, which refers to combining HDRT with LDRT, can reap the advantages of both. Clinical data have also indicated a promising potential. However, there are still questions to be addressed in order to put this novel combination therapy into clinical practice. For example, the selection of treatment site, treatment volume, the sequencing of high-dose radiotherapy and low-dose radiotherapy, combined immunotherapy, and so on. This review summarizes the current evidence supporting the use of HDRT + LDRT, explains possible immune biology mechanisms of this ‘hybrid’ radiotherapy, raises questions to be considered when working out individualized treatment plans, and lists possible avenues to increase efficiency in stimulating anti-tumor immunity using high-dose plus low-dose radiotherapy.

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Yang, Li, Pengtao Liu, Xuncheng Wang, Aolin Jia, Diqiu Ren, Yaru Tang, Yaqi Tang, Xing Wang Deng et Guangming He. « A central circadian oscillator confers defense heterosis in hybrids without growth vigor costs ». Nature Communications 12, n^o 1 (19 avril 2021). http://dx.doi.org/10.1038/s41467-021-22268-z.

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AbstractPlant immunity frequently incurs growth penalties, which known as the trade-off between immunity and growth. Heterosis, the phenotypic superiority of a hybrid over its parents, has been demonstrated for many traits but rarely for disease resistance. Here, we report that the central circadian oscillator, CCA1, confers heterosis for bacterial defense in hybrids without growth vigor costs, and it even significantly enhances the growth heterosis of hybrids under pathogen infection. The genetic perturbation of CCA1 abrogated heterosis for both defense and growth in hybrids. Upon pathogen attack, the expression of CCA1 in F1 hybrids is precisely modulated at different time points during the day by its rhythmic histone modifications. Before dawn of the first infection day, epigenetic activation of CCA1 promotes an elevation of salicylic acid accumulation in hybrids, enabling heterosis for defense. During the middle of every infection day, diurnal epigenetic repression of CCA1 leads to rhythmically increased chlorophyll synthesis and starch metabolism in hybrids, effectively eliminating the immunity-growth heterosis trade-offs in hybrids.

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Calvo-Baltanás, Vanesa, Jinge Wang et Eunyoung Chae. « Hybrid Incompatibility of the Plant Immune System : An Opposite Force to Heterosis Equilibrating Hybrid Performances ». Frontiers in Plant Science 11 (16 février 2021). http://dx.doi.org/10.3389/fpls.2020.576796.

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Hybridization is a core element in modern rice breeding as beneficial combinations of two parental genomes often result in the expression of heterosis. On the contrary, genetic incompatibility between parents can manifest as hybrid necrosis, which leads to tissue necrosis accompanied by compromised growth and/or reduced reproductive success. Genetic and molecular studies of hybrid necrosis in numerous plant species revealed that such self-destructing symptoms in most cases are attributed to autoimmunity: plant immune responses are inadvertently activated in the absence of pathogenic invasion. Autoimmunity in hybrids predominantly occurs due to a conflict involving a member of the major plant immune receptor family, the nucleotide-binding domain and leucine-rich repeat containing protein (NLR; formerly known as NBS-LRR). NLR genes are associated with disease resistance traits, and recent population datasets reveal tremendous diversity in this class of immune receptors. Cases of hybrid necrosis involving highly polymorphic NLRs as major causes suggest that diversifiedRgene repertoires found in different lineages would require a compatible immune match for hybridization, which is a prerequisite to ensure increased fitness in the resulting hybrids. In this review, we overview recent genetic and molecular findings on hybrid necrosis in multiple plant species to provide an insight on how the trade-off between growth and immunity is equilibrated to affect hybrid performances. We also revisit the cases of hybrid weakness in which immune system components are found or implicated to play a causative role. Based on our understanding on the trade-off, we propose that the immune system incompatibility in plants might play an opposite force to restrict the expression of heterosis in hybrids. The antagonism is illustrated under the plant fitness equilibrium, in which the two extremes lead to either hybrid necrosis or heterosis. Practical proposition from the equilibrium model is that breeding efforts for combining enhanced disease resistance and high yield shall be achieved by balancing the two forces. Reverse breeding toward utilizing genomic data centered on immune components is proposed as a strategy to generate elite hybrids with balanced immunity and growth.

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Dai, Xiaoguang, Zhiwen Liu, Xiaoyi Zhao, Kangli Guo, Xiaokang Ding, Fu‐Jian Xu et Nana Zhao. « NIR‐II‐Responsive Hybrid System Achieves Cascade‐Augmented Antitumor Immunity via Genetic Engineering of Both Bacteria and Tumor Cells ». Advanced Materials, 26 août 2024. http://dx.doi.org/10.1002/adma.202407927.

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AbstractThe combination of nanoparticles and tumor‐targeting bacteria for cancer immunotherapy can overcome the shortcomings of poor nanoparticle accumulation, limited penetration, and restricted distribution. However, it remains a great challenge for the hybrid system to improve therapeutic efficacy through the simultaneous and controllable regulation of immune cells and tumor cells. Herein, a hybrid therapeutic platform is rationally designed to achieve immune cascade‐augmented cancer immunotherapy. To construct the hybrids, photothermal nanoparticles responsive to light in the second near‐infrared (NIR‐II) region are conjugated onto the surface of engineered bacteria through pH‐responsive Schiff base bonds. Taking advantage of the hypoxia targeting and deep penetration characteristics of the bacteria, the hybrids can accumulate at tumor sites. Then nanoparticles detach from the bacteria to realize genetic engineering of tumor cells, which induces tumor cell apoptosis and down‐regulate the expression of programmed cell death ligand 1 to alleviate immunosuppressive tumor microenvironment. The mild photothermal heating can not only induce tumor‐associated antigen release, but also trigger sustainable expression of cytokine interleukin‐2. Notably, a synergistic antitumor effect is achieved between the process of p53 transfection and NIR‐II light‐activated genetic engineering of bacteria. This work proposes a facile strategy for the construction of hybrid system to achieve cascade‐augmented cancer immunotherapy.

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& et al., Simakove. « RESULTS OF NEW TRENDS OF POTATO BREEDING PROGRAMS DEVELOPED IN RUSSSIA ». IRAQI JOURNAL OF AGRICULTURAL SCIENCES 49, n^o 4 (1 septembre 2018). http://dx.doi.org/10.36103/ijas.v49i4.67.

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The article presents the results of introgression of valuable genes from wild and cultivated species of Solanum and varieties of the world collection (CIP) to selection varieties in the production of backcross hybrids, selection of recombinants in backcross generations and in offspring from crossbred crosses among themselves, as well as special parent lines for implementation of programs in various areas of potato breeding. Studies were conducted to determine the effectiveness of different types of crossing during backcrossing in the frequency of occurrence of recombinant forms with high rates of polygenic traits in the hybrid progeny. Hybrids-backcrosses for immunity to virus Y, field resistance to late blight and resistance to the pathogen Ro1 of the golden potato nematode were evaluated by the method of artificial infection in pot-plant in a greenhouse. Analysis of hybrid progeny for starch content and suitability for processing by the color of chips was carried out under laboratory conditions. According to the results of the analysis of the pedigrees of 10 varieties of potato originating from the two forms of S. chacoense, a high efficiency of recurrent accumulation crosses providing introgression of the dominant immunity genes to the virus Y is revealed, as well as resistance to alternaria, heat and drought. Medium-late varieties with high field resistance of leaves and tubers were created on the basis of unstable to the late blight hybrid (F1 S. chacoense 55 d x Agra) and 3 recurrent crosses. In this case, varieties with medium field resistance to late blight participated in backcrossing. When assessing the collection of wild species for resistance to the pathogen Ro1 of the golden potato nematode, only one new source of S. chacoense 58 d was detected. Analysis of the cleavage in resistance to nematode among populations from the crossing of three-species hybrids (vrn x chc) x tbr and backcross hybrids (vrn x chc) x tbr2 confirmed control of the trait by one dominant gene, which facilitates selection for this feature. Based on the analysis of the frequency of occurrence of hybrids with different starch content in the fissile offspring, it is established that this feature is controlled by a small amount of pure additively acting genes. In the hybrid populations studied, the symmetrical frequency distribution, the presence of transgressions, and the high correlation between the average starch content of parental forms and the average offspring were observed. In a comparative assessment of 36 hybrid populations on the suitability for processing for potato products, methods for selecting parental forms for crossing and timing of the evaluation of the trait in different periods of tuber storage have been identified. Twenty-two hybrids are identified that are suitable for processing during the entire storage period without reconditioning. An increase in the efficiency of the selection process was noted in the repeated use of identical hybrid populations for selection in various environmental and geographical conditions, which significantly reduces the financial costs of creating a variety.

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Rothoeft, T., C. Maier, A. Talarico, A. Hoffmann, A. Schlegtendal, B. Lange, A. Petersmann et al. « Natural and hybrid immunity after SARS-CoV-2 infection in children and adolescents ». Infection, 18 mars 2024. http://dx.doi.org/10.1007/s15010-024-02225-w.

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Abstract Purpose In contrast to adults, immune protection against SARS-CoV-2 in children and adolescents with natural or hybrid immunity is still poorly understood. The aim of this study was to analyze different immune compartments in different age groups and whether humoral immune reactions correlate with a cellular immune response. Methods 72 children and adolescents with a preceding SARS-CoV-2 infection were recruited. 37 were vaccinated with an RNA vaccine (BNT162b2). Humoral immunity was analyzed 3–26 months (median 10 months) after infection by measuring Spike protein (S), nucleocapsid (NCP), and neutralizing antibodies (nAB). Cellular immunity was analyzed using a SARS-CoV-2-specific interferon-γ release assay (IGRA). Results All children and adolescents had S antibodies; titers were higher in those with hybrid immunity (14,900 BAU/ml vs. 2118 BAU/ml). NCP antibodies were detectable in > 90%. Neutralizing antibodies (nAB) were more frequently detected (90%) with higher titers (1914 RLU) in adolescents with hybrid immunity than in children with natural immunity (62.5%, 476 RLU). Children with natural immunity were less likely to have reactive IGRAs (43.8%) than adolescents with hybrid immunity (85%). The amount of interferon-γ released by T cells was comparable in natural and hybrid immunity. Conclusion Spike antibodies are the most reliable markers to monitor an immune reaction against SARS-CoV-2. High antibody titers of spike antibodies and nAB correlated with cellular immunity, a phenomenon found only in adolescents with hybrid immunity. Hybrid immunity is associated with markedly higher antibody titers and a higher probability of a cellular immune response than a natural immunity.

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