Journal articles: 'Adsorbed antigen'

1

Zhang, Zhigang, Tianying Zhang, Lu Cao, Xin Wang, Jiali Cao, Xiaofen Huang, Yashuang Cai, et al. "Simultaneous in situ visualization and quantitation of dual antigens adsorbed on adjuvants using high content analysis." Nanomedicine 14, no. 19 (October 2019): 2535–48. http://dx.doi.org/10.2217/nnm-2019-0016.

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Aim: Traditional antigenicity assay requires antigen recovery from the particulate adjuvants prior to analysis. An in situ method was developed for interrogating vaccine antigens with monoclonal antibodies while being adsorbed on adjuvants. Materials & methods: The fluorescence imaging-based high content analysis was used to visualize the antigen distribution on adjuvant agglomerates and to analyze the antigenicity for adsorbed antigens. Results: Simultaneous visualization and quantitation were achieved for dual antigens in a bivalent human papillomavirus vaccine with uniquely labeled antibodies. Good agreement was observed between the in situ multiplexed assays with well-established sandwich enzyme-linked immunosorbent assays. Conclusion: The streamlined procedures and the amenability for multiplexing make the in situ antigenicity analysis a favorable choice for in vitro functional assessment of bionanoparticles as vaccine antigens.

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Laera, Donatello, Camilla Scarpellini, Simona Tavarini, Barbara Baudner, Agnese Marcelli, Carlo Pergola, Malte Meppen, and Derek T. O’Hagan. "Maturation of Aluminium Adsorbed Antigens Contributes to the Creation of Homogeneous Vaccine Formulations." Vaccines 11, no. 1 (January 11, 2023): 155. http://dx.doi.org/10.3390/vaccines11010155.

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Although aluminium-based vaccines have been used for almost over a century, their mechanism of action remains unclear. It is established that antigen adsorption to the adjuvant facilitates delivery of the antigen to immune cells at the injection site. To further increase our understanding of aluminium-based vaccines, it is important to gain additional insights on the interactions between the aluminium and antigens, including antigen distribution over the adjuvant particles. Immuno-assays can further help in this regard. In this paper, we evaluated how established formulation strategies (i.e., sequential, competitive, and separate antigen addition) applied to four different antigens and aluminium oxyhydroxide, lead to formulation changes over time. Results showed that all formulation samples were stable, and that no significant changes were observed in terms of physical-chemical properties. Antigen distribution across the bulk aluminium population, however, did show a maturation effect, with some initial dependence on the formulation approach and the antigen adsorption strength. Sequential and competitive approaches displayed similar results in terms of the homogeneity of antigen distribution across aluminium particles, while separately adsorbed antigens were initially more highly poly-dispersed. Nevertheless, the formulation sample prepared via separate adsorption also reached homogeneity according to each antigen adsorption strength. This study indicated that antigen distribution across aluminium particles is a dynamic feature that evolves over time, which is initially influenced by the formulation approach and the specific adsorption strength, but ultimately leads to homogeneous formulations.

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Oksanich, A. S., A. G. Krasko, T. G. Samartseva, E. L. Gasich, and G. M. Ignatyev. "The use of quantitative enzyme-linked immunosorbent assay for the determination of S-antigen concentration in whole-virion inactivated adsorbed coronavirus vaccines." Biological Products. Prevention, Diagnosis, Treatment 22, no. 4 (November 25, 2022): 405–13. http://dx.doi.org/10.30895/2221-996x-2022-22-4-405-413.

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The severe consequences and high mortality of COVID-19 prompted the development of a wide range of preventive vaccines. The first vaccines to be tested were developed in China and formulated as inactivated SARS-CoV-2 adsorbed on aluminium hydroxide. One of the quality indicators for inactivated adsorbed vaccines is the degree of adsorption, which can be used to control the content not only of non-adsorbed antigen, but also of specific antigen in one dose of a vaccine.The aim of the study was to investigate the possibility of desorbing SARS-CoV-2 antigen from formulated adsorbed vaccines and the possibility of measuring its concentration using the BioScan-SARS-CoV-2 (S) ELISA kit for SARS-CoV-2 S-protein content determination.Materials and methods: the study used four batches of BBIBP-CorV by CNBG, Sinopharm (China) and three batches of CoronaVac by Sinovac Biotech (China). The authors desorbed SARS-CoV-2 S antigen in accordance with monograph FS.3.3.1.0029.15 of the State Pharmacopoeia of the Russian Federation (Ph. Rus.), edition XIV, and quantified it using the BioScan-SARS-CoV-2 (S) ELISA kit by Bioservice Biotechnology Co. Ltd. (Russia).Results: mean S-antigen concentrations in the desorbed samples ranged from 61 to 129 ng/mL for BBIBP-CorV and from 461 to 533 ng/mL for CoronaVac.Conclusions: the study demonstrated the possibility of specific SARS-CoV-2 antigen desorption from the surface of aluminium hydroxide using the Ph. Rus. method, as well as the possibility of S-antigen quantification in desorbed medicinal products and supernatants using the BioScan-SARS-CoV-2 (S) ELISA kit. The authors observed 3.6- to 8.7-fold difference between the S-antigen concentrations of the desorbed preparations by the two manufacturers.

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TRUJILLO, Mary, Luz M. SALAZAR, and Jesús VALENCIA. "VACCINE FORMULATION: ADSORPTION OF <I>Plasmodium falciparum</I> MSP-1 PEPTIDE 1585 ON ALUMINIUM HYDROXIDE." Vitae 18, no. 2 (September 2, 2011): 183–91. http://dx.doi.org/10.17533/udea.vitae.10070.

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The Plasmodium falciparum merozoite surface protein 1 has been studied due to its potential to become a vaccine; likewise, the peptide 1585 which is located in the 42-kDa amino-terminal fragment induces protective immunity in primates. Despite the importance of antigen adsorption in the formulation and production of vaccines containing aluminium adjuvant, the protein fragment adsorption on aluminium hydroxide has not been thoroughly studied. Electrostatic attraction, hydrophobic interaction and ligand exchange have been identified as the major mechanisms involved in antigen retention on the adsorbent surface. Peptide 1585 was synthesized, and its solubility, adsorption on aluminium hydroxide, as well as its molecule release have been studied here. Results allowed us to raise a model for the adsorption and release of this peptide, which are important parameters to establish optimal conditions for peptideadsorbent interaction and, therefore, their response as a vaccine. Results also established the reversibility of such process due to the phosphate ion effect. Thus, this work provides a starting point for research works, leading to further development of vaccine formulations containing highly purified synthetic antigens adsorbed on aluminium adjuvant.

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Miletich, JP, and GJ Jr Broze. "Human plasma protein Z antigen: range in normal subjects and effect of warfarin therapy." Blood 69, no. 6 (June 1, 1987): 1580–86. http://dx.doi.org/10.1182/blood.v69.6.1580.bloodjournal6961580.

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In contrast to the other well-studied vitamin K-dependent proteins that circulate in plasma, protein Z antigen is much more variable. The concentration in plasmas collected in EDTA from 455 normal, healthy donors is normally distributed with a mean of 2.9 micrograms/mL (46 nmol/L) and a SD of 1.0 microgram/mL (95% interval of 32% to 168% of the mean). No significant correlation to age or sex could be detected. In comparison, the concentration of protein C antigen measured with the same type of assay on the same 455 samples has a log normal distribution with a mean of 4.0 micrograms/mL (65 nmol/L) and a 95% interval of 70% to 138% of the mean. Also in marked contrast to other plasma vitamin K-dependent proteins, the total protein Z antigen level is extremely low in patients on stable warfarin therapy (range 1% to 16% of normal). Moreover, even though greater than 95% of the antigen in normal plasmas adsorbs to barium citrate (a crude reflection of the presence of gamma-carboxyglutamic acid (Gla) residues), in the patients taking warfarin almost all of the small amount of the antigen failed to adsorb, suggesting that virtually no protein Z had its full complement of Gla residues. Total protein C antigen in the same 25 patients averaged 53% of normal (34% to 72%) and 54% (average) of the total remaining antigen still adsorbed to barium citrate. The concentration of protein Z antigen in the plasma of a normal individual given a loading dose of warfarin fell at an initial rate of approximately 20% a day, indicating a plasma half-life (t1/2) of 2 to 3 days.

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Dunstan, RA, MB Simpson, RW Knowles, and WF Rosse. "The origin of ABH antigens on human platelets." Blood 65, no. 3 (March 1, 1985): 615–19. http://dx.doi.org/10.1182/blood.v65.3.615.615.

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Abstract ABH antigens are present on platelets from individuals of the corresponding red cell phenotype, but the extent to which these antigens are intrinsic or adsorbed remains undefined. To evaluate platelets for intrinsic H substance, an IgM mouse monoclonal antibody against type 2H chain (the intrinsic H structure found on erythrocytes) was labeled with 125I and incubated with platelets from donors of different ABO type. The antibody showed dose-response saturation curves, and binding to platelets paralleled that of the red cell ABO type, with O greater than B greater than A1 greater than A1B greater Oh cells, giving a single factor variance F of 190 (P less than .0005). Passive adsorption of A antigens by platelets has been previously reported. To verify this phenomenon for A and B antigens and to quantitate the elution of A and B antigens from platelets, the following assay system was used. Platelets from group A1 and B donors were incubated in plasma from group O donors, and platelets from group O donors were incubated in plasma from different ABO, Lewis, and presumed secretor-type donors. Human IgG anti-A or anti-B was added to the platelets. The amount of antibody bound was determined with a 125I- labeled mouse monoclonal anti-human IgG. When incubated for 96 hours in group O plasma, group A1 platelets showed a 45% to 50% decrease in binding of anti-A. There was no significant change in the level of type 2H antigen on these platelets during the same incubation period. Group O platelets incubated in A or B plasmas rapidly acquired the antigens, but if returned to their original plasma, 95% of this passively adsorbed antigen eluted off within 18 hours. The maximum uptake of A and B substances was influenced by the Lewis and secretor type of donor plasma. Our present study demonstrates that ABH antigens on platelets consist of type 2H chains, which are presumably intrinsic as when found on red cells, and of passively adsorbed ABH structures, which are presumably type 1H chains.

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Dunstan, RA, MB Simpson, RW Knowles, and WF Rosse. "The origin of ABH antigens on human platelets." Blood 65, no. 3 (March 1, 1985): 615–19. http://dx.doi.org/10.1182/blood.v65.3.615.bloodjournal653615.

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ABH antigens are present on platelets from individuals of the corresponding red cell phenotype, but the extent to which these antigens are intrinsic or adsorbed remains undefined. To evaluate platelets for intrinsic H substance, an IgM mouse monoclonal antibody against type 2H chain (the intrinsic H structure found on erythrocytes) was labeled with 125I and incubated with platelets from donors of different ABO type. The antibody showed dose-response saturation curves, and binding to platelets paralleled that of the red cell ABO type, with O greater than B greater than A1 greater than A1B greater Oh cells, giving a single factor variance F of 190 (P less than .0005). Passive adsorption of A antigens by platelets has been previously reported. To verify this phenomenon for A and B antigens and to quantitate the elution of A and B antigens from platelets, the following assay system was used. Platelets from group A1 and B donors were incubated in plasma from group O donors, and platelets from group O donors were incubated in plasma from different ABO, Lewis, and presumed secretor-type donors. Human IgG anti-A or anti-B was added to the platelets. The amount of antibody bound was determined with a 125I- labeled mouse monoclonal anti-human IgG. When incubated for 96 hours in group O plasma, group A1 platelets showed a 45% to 50% decrease in binding of anti-A. There was no significant change in the level of type 2H antigen on these platelets during the same incubation period. Group O platelets incubated in A or B plasmas rapidly acquired the antigens, but if returned to their original plasma, 95% of this passively adsorbed antigen eluted off within 18 hours. The maximum uptake of A and B substances was influenced by the Lewis and secretor type of donor plasma. Our present study demonstrates that ABH antigens on platelets consist of type 2H chains, which are presumably intrinsic as when found on red cells, and of passively adsorbed ABH structures, which are presumably type 1H chains.

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Werthén, Maria, and Håkan Nygren. "Cooperativity in the antibody binding to surface-adsorbed antigen." Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology 1162, no. 3 (March 1993): 326–32. http://dx.doi.org/10.1016/0167-4838(93)90298-6.

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9

Miletich, JP, and GJ Jr Broze. "Human plasma protein Z antigen: range in normal subjects and effect of warfarin therapy." Blood 69, no. 6 (June 1, 1987): 1580–86. http://dx.doi.org/10.1182/blood.v69.6.1580.1580.

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Abstract In contrast to the other well-studied vitamin K-dependent proteins that circulate in plasma, protein Z antigen is much more variable. The concentration in plasmas collected in EDTA from 455 normal, healthy donors is normally distributed with a mean of 2.9 micrograms/mL (46 nmol/L) and a SD of 1.0 microgram/mL (95% interval of 32% to 168% of the mean). No significant correlation to age or sex could be detected. In comparison, the concentration of protein C antigen measured with the same type of assay on the same 455 samples has a log normal distribution with a mean of 4.0 micrograms/mL (65 nmol/L) and a 95% interval of 70% to 138% of the mean. Also in marked contrast to other plasma vitamin K-dependent proteins, the total protein Z antigen level is extremely low in patients on stable warfarin therapy (range 1% to 16% of normal). Moreover, even though greater than 95% of the antigen in normal plasmas adsorbs to barium citrate (a crude reflection of the presence of gamma-carboxyglutamic acid (Gla) residues), in the patients taking warfarin almost all of the small amount of the antigen failed to adsorb, suggesting that virtually no protein Z had its full complement of Gla residues. Total protein C antigen in the same 25 patients averaged 53% of normal (34% to 72%) and 54% (average) of the total remaining antigen still adsorbed to barium citrate. The concentration of protein Z antigen in the plasma of a normal individual given a loading dose of warfarin fell at an initial rate of approximately 20% a day, indicating a plasma half-life (t1/2) of 2 to 3 days.

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10

Zhao, Xiubo, Fang Pan, Luis Garcia-Gancedo, Andrew J. Flewitt, Gregory M. Ashley, Jikui Luo, and Jian R. Lu. "Interfacial recognition of human prostate-specific antigen by immobilized monoclonal antibody: effects of solution conditions and surface chemistry." Journal of The Royal Society Interface 9, no. 75 (May 2, 2012): 2457–67. http://dx.doi.org/10.1098/rsif.2012.0148.

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The specific recognition between monoclonal antibody (anti-human prostate-specific antigen, anti-hPSA) and its antigen (human prostate-specific antigen, hPSA) has promising applications in prostate cancer diagnostics and other biosensor applications. However, because of steric constraints associated with interfacial packing and molecular orientations, the binding efficiency is often very low. In this study, spectroscopic ellipsometry and neutron reflection have been used to investigate how solution pH, salt concentration and surface chemistry affect antibody adsorption and subsequent antigen binding. The adsorbed amount of antibody was found to vary with pH and the maximum adsorption occurred between pH 5 and 6, close to the isoelectric point of the antibody. By contrast, the highest antigen binding efficiency occurred close to the neutral pH. Increasing the ionic strength reduced antibody adsorbed amount at the silica–water interface but had little effect on antigen binding. Further studies of antibody adsorption on hydrophobic C8 (octyltrimethoxysilane) surface and chemical attachment of antibody on (3-mercaptopropyl)trimethoxysilane/4-maleimidobutyric acid N -hydroxysuccinimide ester-modified surface have also been undertaken. It was found that on all surfaces studied, the antibody predominantly adopted the ‘flat on’ orientation, and antigen-binding capabilities were comparable. The results indicate that antibody immobilization via appropriate physical adsorption can replace elaborate interfacial molecular engineering involving complex covalent attachments.

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Bellanti, Joseph A., Feng-Ying C. Lin, Chiayung Chu, Joseph Shiloach, Stephen H. Leppla, German A. Benavides, Arthur Karpas, et al. "Phase 1 Study of a Recombinant Mutant Protective Antigen of Bacillus anthracis." Clinical and Vaccine Immunology 19, no. 2 (December 21, 2011): 140–45. http://dx.doi.org/10.1128/cvi.05556-11.

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ABSTRACTA phase 1 study of a recombinant mutant protective antigen (rPA) vaccine was conducted in 186 healthy adults aged 18 to 45 years. Volunteers were randomized to receive one of three formulations of rPA (formalin treated, alum adsorbed, or both), in 10- or 20-μg dosages each, or the licensed vaccine, AVA. Three injections were given at 2-month intervals and a 4th 1 year after the 3rd. Vaccinees were examined at the clinic once following each injection, at 48 to 72 h postinjection. Adverse reactions were recorded in diaries for 7 days. Sera were collected before each injection and 1 week after the 1st, 2 weeks after the 3rd and 4th, and 1 year after the 4th. Serum anti-PA IgG was assayed by enzyme-linked immunosorbent assay (ELISA) and toxin neutralization assay (TNA). All formulations at both dosages were safe and immunogenic, inducing booster responses, with the highest antibody levels following the 4th injection (354 to 732 μg/ml). The lowest levels were induced by the formalin-only-treated rPA; there was no statistical difference between levels induced by alum-adsorbed and formalin-treated/alum-adsorbed rPA or by the two dosages. The antibody levels declined in all groups during the 1-year intervals after the 3rd and 4th injections but less so during the 2nd year, after the 4th injection (fold decreases were 10 to 25 versus 3.4 to 7.0,P< 0.001). There were too few AVA recipients for statistical comparisons, but their antibody levels followed those of rPA. Anti-rPA measured by ELISA correlated with TNA titers (r= 0.97). These data support studying alum-adsorbed rPA in children.

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Xie, Hang, Ihsan Gursel, Bruce E. Ivins, Manmohan Singh, Derek T. O'Hagan, Jeffrey B. Ulmer, and Dennis M. Klinman. "CpG Oligodeoxynucleotides Adsorbed onto Polylactide-Co-Glycolide Microparticles Improve the Immunogenicity and Protective Activity of the Licensed Anthrax Vaccine." Infection and Immunity 73, no. 2 (February 2005): 828–33. http://dx.doi.org/10.1128/iai.73.2.828-833.2005.

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ABSTRACT To reduce the biothreat posed by anthrax, efforts are under way to improve the protection afforded by vaccination. This work examines the ability of immunostimulatory CpG oligodeoxynucleotides (ODN) adsorbed onto cationic polylactide-co-glycolide (PLG) microparticles (CpG ODN-PLG) to accelerate and boost the protective immunity elicited by Anthrax Vaccine Adsorbed (AVA, the licensed human anthrax vaccine). The results indicate that coadministering CpG ODN-PLG with AVA induces a stronger and faster immunoglobulin G response against the protective antigen of anthrax than AVA alone. Immunized mice were protected from lethal anthrax challenge within 1 week of vaccination with CpG ODN-PLG plus AVA, with the level of protection correlating with serum immunoglobulin G anti-protective antigen titers.

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Morefield, Garry L., Harm HogenEsch, J. Paul Robinson, and Stanley L. Hem. "Distribution of adsorbed antigen in mono-valent and combination vaccines." Vaccine 22, no. 15-16 (May 2004): 1973–84. http://dx.doi.org/10.1016/j.vaccine.2003.10.040.

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Beaman, Blaine L., and LoVelle Beaman. "Filament Tip-Associated Antigens Involved in Adherence to and Invasion of Murine Pulmonary Epithelial Cells In Vivo and HeLa Cells In Vitro by Nocardia asteroides." Infection and Immunity 66, no. 10 (October 1, 1998): 4676–89. http://dx.doi.org/10.1128/iai.66.10.4676-4689.1998.

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ABSTRACT The interactions of Nocardia asteroides GUH-2 with pulmonary epithelial cells of C57BL/6 mice and with HeLa cells were studied. Electron microscopy demonstrated that only the tips of log-phase cells penetrated pulmonary epithelial cells following intranasal administration, and nocardiae were recovered from the brain. Coccobacillary cells neither invaded nor disseminated. Serum from immunized mice (IMS) decreased attachment to and penetration of pulmonary epithelial cell surfaces by log-phase GUH-2 and inhibited spread to the brain. IMS was adsorbed against stationary-phase cells. Western immunoblots suggested that this adsorbed IMS was reactive primarily with 43- and 62-kDa proteins. Immunofluorescence showed that adsorbed IMS preferentially labeled the tips of log-phase GUH-2 cells. Since this IMS was reactive to culture filtrate antigens, several of these proteins were cut from gels, and mice were immunized. Sera against 62-, 55-, 43-, 36-, 31-, and 25-kDa antigens were obtained. The antisera against the 43- and 36-kDa proteins labeled the filament tips of GUH-2 cells. Only the antiserum against the 43-kDa antigen increased pulmonary clearance, inhibited apical attachment to and penetration of pulmonary epithelial cells, and prevented spread to the brain. An in vitro model with HeLa cells demonstrated that the tips of log-phase cells of GUH-2 adhered to and penetrated the surface of HeLa cells. Invasion assays with amikacin treatment demonstrated that nocardiae were internalized. Adsorbed IMS blocked attachment to and invasion of these cells. These data suggested that a filament tip-associated 43-kDa protein was involved in attachment to and invasion of pulmonary epithelial cells and HeLa cells by N. asteroides GUH-2.

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Ukidve, Anvay, Zongmin Zhao, Alexandra Fehnel, Vinu Krishnan, Daniel C. Pan, Yongsheng Gao, Abhirup Mandal, Vladimir Muzykantov, and Samir Mitragotri. "Erythrocyte-driven immunization via biomimicry of their natural antigen-presenting function." Proceedings of the National Academy of Sciences 117, no. 30 (July 14, 2020): 17727–36. http://dx.doi.org/10.1073/pnas.2002880117.

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Erythrocytes naturally capture certain bacterial pathogens in circulation, kill them through oxidative stress, and present them to the antigen-presenting cells (APCs) in the spleen. By leveraging this innate immune function of erythrocytes, we developed erythrocyte-driven immune targeting (EDIT), which presents nanoparticles from the surface of erythrocytes to the APCs in the spleen. Antigenic nanoparticles were adsorbed on the erythrocyte surface. By engineering the number density of adsorbed nanoparticles, (i.e., the number of nanoparticles loaded per erythrocyte), they were predominantly delivered to the spleen rather than lungs, which is conventionally the target of erythrocyte-mediated delivery systems. Presentation of erythrocyte-delivered nanoparticles to the spleen led to improved antibody response against the antigen, higher central memory T cell response, and lower regulatory T cell response, compared with controls. Enhanced immune response slowed down tumor progression in a prophylaxis model. These findings suggest that EDIT is an effective strategy to enhance systemic immunity.

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Wu, J. Y., B. H. Gardner, C. I. Murphy, J. R. Seals, C. R. Kensil, J. Recchia, G. A. Beltz, G. W. Newman, and M. J. Newman. "Saponin adjuvant enhancement of antigen-specific immune responses to an experimental HIV-1 vaccine." Journal of Immunology 148, no. 5 (March 1, 1992): 1519–25. http://dx.doi.org/10.4049/jimmunol.148.5.1519.

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Abstract The adjuvant activity of a single highly purified saponin from the soap bark tree Quillaja saponaria was evaluated by using it as a component in an experimental vaccine containing rHIV-1 envelope protein (HIV-1 160D) adsorbed to alum. BALB/c mice immunized with experimental vaccine formulations containing the saponin adjuvant QS-21 produced significantly higher titers of antibodies than mice vaccinated with only the alum-adsorbed HIV-1 160D. Potent amnestic antibody responses to HIV-1 viral proteins were also induced. Ag-specific proliferative responses to recombinant proteins and to three variants of HIV-1 were significantly increased using QS-21 as an adjuvant. Alum-adsorbed HIV-1 160D failed to induce measurable proliferative responses to inactivated HIV-1 viruses, but group-specific proliferative responses were raised when the QS-21 adjuvant was used in the vaccine formulation. MHC class I restricted CTL specific for the immunodominant V-3 loop were induced but only when the QS-21 adjuvant was included in the vaccine formulation. The production of serine esterase by Ag-activated splenic mononuclear cells, indicating the maturation of precursor CTL, was used as a secondary measure of CTL activity, and this response was also increased. The specificity of antibody responses was not significantly broadened using QS-21; the adjuvant increased the immune recognition of epitopes throughout the HIV-1 glycoprotein 160. However, the specificity of the proliferation and serine esterase responses was broadened, suggesting that the QS-21 augmented cell-mediated immune responses specific for epitopes outside of the V-3 loop. Additionally, the QS-21 adjuvant appeared to induce recognition of weakly immunogenic epitopes that were not recognized using only alum-adsorbed HIV-1 160D. The ability of QS-21 to augment both antibody and cell-mediated immune responses suggests that this adjuvant could be a valuable component in subunit vaccines.

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Kao, KJ, DJ Cook, and JC Scornik. "Quantitative analysis of platelet surface HLA by W6/32 anti-HLA monoclonal antibody." Blood 68, no. 3 (September 1, 1986): 627–32. http://dx.doi.org/10.1182/blood.v68.3.627.627.

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Abstract Class I molecules of human major histocompatibility complex (HLA) are the most important antigenic system in determining the survival of transfused platelets in alloimmunized patients. Platelets with reduced expression of a specific type of HLA antigen may escape specific anti- HLA antibody-mediated destruction. By using 125I-labeled Fab fragments of W6/32 anti-HLA monoclonal antibody and competitive protein binding assays, we measured the range of total HLA concentrations on platelets. In 12 individuals examined, the mean number of HLA-A, B, and C molecules per platelet was 81,587 +/- 20,016 (mean +/- SD); its range was between 54,782 to 116,185 molecules per platelet. After treatment with chloroquine, 79.9 +/- 7.0% (mean +/- SD, n = 6) of HLA antigens were removed from platelets as determined by binding of 125I-W6/32 Fab. A similar result was obtained when HLA antigens on chloroquine-treated platelets were evaluated with immunofluorescence flow cytometry. In contrast, chloroquine treatment did not remove integral membrane protein such as P1A1 antigens on platelets. The presence of HLA antigens in the chloroquine eluate of platelets could be demonstrated to contain HLA antigens similar in mol wts to intact class I molecules by an immunoblotting technique. These data suggest that 70% to 80% of platelet HLA antigens are adsorbed and that such HLA antigens are not proteolytic products of integral membrane class I molecules. The origin of the adsorbed platelet HLA-antigens remains to be determined.

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Kao, KJ, DJ Cook, and JC Scornik. "Quantitative analysis of platelet surface HLA by W6/32 anti-HLA monoclonal antibody." Blood 68, no. 3 (September 1, 1986): 627–32. http://dx.doi.org/10.1182/blood.v68.3.627.bloodjournal683627.

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Class I molecules of human major histocompatibility complex (HLA) are the most important antigenic system in determining the survival of transfused platelets in alloimmunized patients. Platelets with reduced expression of a specific type of HLA antigen may escape specific anti- HLA antibody-mediated destruction. By using 125I-labeled Fab fragments of W6/32 anti-HLA monoclonal antibody and competitive protein binding assays, we measured the range of total HLA concentrations on platelets. In 12 individuals examined, the mean number of HLA-A, B, and C molecules per platelet was 81,587 +/- 20,016 (mean +/- SD); its range was between 54,782 to 116,185 molecules per platelet. After treatment with chloroquine, 79.9 +/- 7.0% (mean +/- SD, n = 6) of HLA antigens were removed from platelets as determined by binding of 125I-W6/32 Fab. A similar result was obtained when HLA antigens on chloroquine-treated platelets were evaluated with immunofluorescence flow cytometry. In contrast, chloroquine treatment did not remove integral membrane protein such as P1A1 antigens on platelets. The presence of HLA antigens in the chloroquine eluate of platelets could be demonstrated to contain HLA antigens similar in mol wts to intact class I molecules by an immunoblotting technique. These data suggest that 70% to 80% of platelet HLA antigens are adsorbed and that such HLA antigens are not proteolytic products of integral membrane class I molecules. The origin of the adsorbed platelet HLA-antigens remains to be determined.

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Frampton, James E., and Susan J. Keam. "Reduced-Antigen, Combined Diphtheria-Tetanus-Acellular Pertussis Vaccine, Adsorbed (Boostrix?? US Formulation)." Pediatric Drugs 8, no. 3 (2006): 189–95. http://dx.doi.org/10.2165/00148581-200608030-00005.

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Halperin, Scott A. "Reduced-Antigen, Combined Diphtheria-Tetanus-Acellular Pertussis Vaccine, Adsorbed (Boostrix?? US Formulation)." Pediatric Drugs 8, no. 3 (2006): 196. http://dx.doi.org/10.2165/00148581-200608030-00006.

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Theeten, Heidi, Pierre Van Damme, and Marie Van der Wielen. "Reduced-Antigen, Combined Diphtheria-Tetanus-Acellular Pertussis Vaccine, Adsorbed (Boostrix?? US Formulation)." Pediatric Drugs 8, no. 3 (2006): 196. http://dx.doi.org/10.2165/00148581-200608030-00007.

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McCormack, Paul L. "Reduced-Antigen, Combined Diphtheria, Tetanus and Acellular Pertussis Vaccine, Adsorbed (Boostrix®)." Drugs 72, no. 13 (September 2012): 1765–91. http://dx.doi.org/10.2165/11209630-000000000-00000.

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Kanzaki, A., H. Kasuya, K. Yamamura, T. T. Sahin, N. Nomura, T. Shikano, T. Shirota, et al. "Antitumor efficacy of oncolytic herpes simplex virus adsorbed onto antigen-specific lymphocytes." Cancer Gene Therapy 19, no. 4 (January 27, 2012): 292–98. http://dx.doi.org/10.1038/cgt.2011.91.

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Scott, Lesley J., and Paul L. McCormack. "Reduced-Antigen, Combined Diphtheria, Tetanus, and Acellular Pertussis Vaccine, Adsorbed (Boostrix®)." BioDrugs 27, no. 1 (December 18, 2012): 75–81. http://dx.doi.org/10.1007/s40259-012-0009-y.

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Owens, T., and B. Fazekas de St Groth. "Participation of L3T4 in T cell activation in the absence of class II major histocompatibility complex antigens. Inhibition by anti-L3T4 antibodies is a function both of epitope density and mode of presentation of anti-receptor antibody." Journal of Immunology 138, no. 8 (April 15, 1987): 2402–9. http://dx.doi.org/10.4049/jimmunol.138.8.2402.

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Abstract The recognition of many class II major histocompatibility complex (MHC)-associated antigens by T cells requires the participation of the L3T4 molecule. It has been proposed that this molecule acts to stabilize low affinity binding to antigen in association with MHC and thereby increases the avidity of T cell/antigen interactions. By using antibodies against the T cell antigen receptor (TCR) to activate T cells, thereby circumventing the requirement for antigen presenting cells and MHC-associated antigen, we have been able to study the function of L3T4 in the absence of class II MHC. We have used two monoclonal antibodies, KJ16-133.18 and F23.1, that recognize a determinant encoded by the T cell receptor V beta 8 gene family. These antibodies were used to select two clones of T cells with surface phenotype Thy-1.2+, L3T4+, Lyt-2-, KJ16-133.18+, F23.1+, IA-, IE-. One of these clones (E9.D4) was hapten-specific (anti-ABA + Iak), the other (4.35F2) was alloreactive (anti-Iak). Activation of these clones by antigen, concanavalin A (Con A) or by the F23.1 antibody was studied by assaying the production of interleukin 3 (IL 3). Both soluble and solid phase-coupled F23.1 induced T cell activation in the complete absence of class II MHC, immobilized antibody (either Sepharose-coupled or plastic-adsorbed) being more effective. The induction of IL 3 production by suboptimal doses of either Con A or plastic-adsorbed F23.1 was inhibited by the anti-L3T4 antibody GK1.5, as was the response to F23.1 coupled to Sepharose-4B beads. However, the responses to optimal or superoptimal doses of these stimuli were not inhibited. In contrast, weak responses to non-TCR cross-linking stimuli such as phorbol myristate acetate (PMA) or low concentrations of soluble F23.1 were not inhibited by GK1.5 (the latter response was usually slightly enhanced). These results show that anti-L3T4 antibodies are not inherently inhibitory, but require both ligation and cross-linking of the TCR for their effect. We propose a model whereby L3T4 interacts with the TCR during T cell activation. Anti-L3T4 antibodies sterically hinder the formation of TCR complexes and so prevent activation. However, by increasing the epitope density of the activating ligand, the avidity of the T cell/ligand interaction can be increased sufficiently to prevent this disruption.(ABSTRACT TRUNCATED AT 400 WORDS)

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Weissmueller, Nikolas T., Heiko A. Schiffter, Robert C. Carlisle, Christine S. Rollier, and Andrew J. Pollard. "Needle-Free Dermal Delivery of a Diphtheria Toxin CRM197Mutant on Potassium-Doped Hydroxyapatite Microparticles." Clinical and Vaccine Immunology 22, no. 5 (March 25, 2015): 586–92. http://dx.doi.org/10.1128/cvi.00121-15.

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ABSTRACTInjections with a hypodermic needle and syringe (HNS) are the current standard of care globally, but the use of needles is not without limitation. While a plethora of needle-free injection devices exist, vaccine reformulation is costly and presents a barrier to their widespread clinical application. To provide a simple, needle-free, and broad-spectrum protein antigen delivery platform, we developed novel potassium-doped hydroxyapatite (K-Hap) microparticles with improved protein loading capabilities that can provide sustained local antigen presentation and release. K-Hap showed increased protein adsorption over regular hydroxyapatite (P< 0.001), good structural retention of the model antigen (CRM197) with 1% decrease in α-helix content and no change in β-sheet content upon adsorption, and sustained releasein vitro. Needle-free intradermal powder inoculation with K-Hap–CRM197induced significantly higher IgG1 geometric mean titers (GMTs) than IgG2a GMTs in a BALB/c mouse model (P< 0.001) and induced IgG titer levels that were not different from the current clinical standard (P> 0.05), namely, alum-adsorbed CRM197by intramuscular (i.m.) delivery. The presented results suggest that K-Hap microparticles may be used as a novel needle-free delivery vehicle for some protein antigens.

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Qin, Lin, Jun Cao, Kun Shao, Fan Tong, Zhihang Yang, Ting Lei, Yazhen Wang, et al. "A tumor-to-lymph procedure navigated versatile gel system for combinatorial therapy against tumor recurrence and metastasis." Science Advances 6, no. 36 (September 2020): eabb3116. http://dx.doi.org/10.1126/sciadv.abb3116.

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Application of cancer vaccines is limited due to their systemic immunotoxicity and inability to satisfy all the steps, including loading of tumor antigens, draining of antigens to lymph nodes (LNs), internalization of antigens by dendritic cells (DCs), DC maturation, and cross-presentation of antigens for T cell activation. Here, we present a combinatorial therapy, based on a α-cyclodextrin (CD)–based gel system, DOX/ICG/CpG-P-ss-M/CD, fabricated by encapsulating doxorubicin (DOX) and the photothermal agent indocyanine green (ICG). Upon irradiation, the gel system exhibited heat-responsive release of DOX and vaccine-like nanoparticles, CpG-P-ss-M, along with chemotherapy- and phototherapy-generated abundant tumor-specific antigen storage in situ. The released CpG-P-ss-M acted as a carrier adsorbed and delivered antigens to LNs, promoting the uptake of antigens by DCs and DC maturation. Notably, combined with PD-L1 blocking, the therapy effectively inhibited primary tumor growth and induced tumor-specific immune response against tumor recurrence and metastasis.

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Rossi, Omar, Maria Grazia Aruta, Alessandra Acquaviva, Francesca Mancini, Francesca Micoli, and Francesca Necchi. "Characterization of Competitive ELISA and Formulated Alhydrogel Competitive ELISA (FAcE) for Direct Quantification of Active Ingredients in GMMA-Based Vaccines." Methods and Protocols 3, no. 3 (August 31, 2020): 62. http://dx.doi.org/10.3390/mps3030062.

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Generalized modules for membrane antigens (GMMA) represent a technology particularly attractive for designing affordable vaccines against Gram-negative bacteria. We explored such technology for the development of O-antigen-based vaccines against Shigella and nontyphoidal Salmonella. Adsorption of GMMA on Alhydrogel was required for abrogation of pyrogenicity in rabbits, and Shigella sonnei GMMA on Alhydrogel was well tolerated and immunogenic in humans. Quantification of key antigens in formulated vaccines was fundamental for release and to check stability overtime. Traditionally, the direct quantification of antigens adsorbed on aluminum salts has been challenging, and the quantification of each active ingredient in multicomponent formulated vaccines has been even more complicated. To directly quantify each active ingredient and unbound drug substances in formulated vaccines, we developed the Formulated Alhydrogel competitive ELISA (FAcE) and the competitive ELISA method, respectively. The methods were both fully characterized, assessing specificity, repeatability, intermediate precision, and accuracy, for S. sonnei OAg quantification, both in a single component or multicomponent GMMA formulation also containing S. flexneri GMMA. The developed immunological methods allowed us to fully characterize Shigella GMMA drug products, supporting their preclinical and clinical development. The same methods, already extended to GMMA from nontyphoidal Salmonella and Neisseria meningitidis, could be potentially extended to any antigen formulated on Alhydrogel.

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Matyas, Gary R., Arthur M. Friedlander, Gregory M. Glenn, Stephen Little, Jianmei Yu, and Carl R. Alving. "Needle-Free Skin Patch Vaccination Method for Anthrax." Infection and Immunity 72, no. 2 (February 2004): 1181–83. http://dx.doi.org/10.1128/iai.72.2.1181-1183.2004.

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ABSTRACT Three immunizations of mice with recombinant protective antigen (rPA) by transcutaneous immunization (TCI) induced long-term neutralizing antibody titers that were superior to those obtained with aluminum-adsorbed rPA. In addition, rPA alone exhibited adjuvant activity for TCI. Forty-six weeks after completion of TCI, 100% protection was observed against lethal anthrax challenge.

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Mollicone, R., T. Caillard, J. Le Pendu, A. Francois, N. Sansonetti, H. Villarroya, and R. Oriol. "Expression of ABH and X (Lex) antigens on platelets and lymphocytes." Blood 71, no. 4 (April 1, 1988): 1113–19. http://dx.doi.org/10.1182/blood.v71.4.1113.1113.

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Abstract We used a panel of reagents, polyclonal and monoclonal antibodies, and lectins to define the expression of the ABH- and Lewis-related specificities on platelets and lymphocytes. We also determined the expression of the alpha 2- and alpha 3-L-fucosyltransferases necessary for their biosynthesis. The antigens that could be detected by immunofluorescence and Western blot analysis were based on type 2 monofucosylated structures. Antibodies directed toward types 1, 3, and 4 ABH-, X- and Lewis-related antigenic determinants were always negative because the small amounts of ABH and Lewis antigens adsorbed from the serum could not be detected by these techniques. The presence of the type 2 ABH antigens on intrinsic glycoproteins was controlled by the H gene. This correlates with the presence of alpha 2-L- fucosyltransferase and the absence of alpha 3-L-fucosyltransferase on platelets. In contrast, ABH antigens were not detected by immunofluorescence on normal peripheral lymphocytes. These cells thus have only the small amounts of antigens adsorbed from the serum, these being under control of the secretor and Lewis genes. This correlates with the absence of alpha 2-L-fucosyltransferase on lymphocytes. When lymphocytes were transformed in vitro by the Epstein-Barr virus (EBV), however, they strongly expressed the X and sialylated X antigens, which are specific markers of normal granulocytes and monocytes, respectively. Treatment of EBV-transformed lymphoblastoid cell lines with 12-O-tetradecanoylphorbol-13-O-acetate significantly decreased the expression of X and sialylated X antigens along with that of surface immunoglobulins, whereas it induced a significant expression of the H antigen under control of the H gene.

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Mollicone, R., T. Caillard, J. Le Pendu, A. Francois, N. Sansonetti, H. Villarroya, and R. Oriol. "Expression of ABH and X (Lex) antigens on platelets and lymphocytes." Blood 71, no. 4 (April 1, 1988): 1113–19. http://dx.doi.org/10.1182/blood.v71.4.1113.bloodjournal7141113.

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We used a panel of reagents, polyclonal and monoclonal antibodies, and lectins to define the expression of the ABH- and Lewis-related specificities on platelets and lymphocytes. We also determined the expression of the alpha 2- and alpha 3-L-fucosyltransferases necessary for their biosynthesis. The antigens that could be detected by immunofluorescence and Western blot analysis were based on type 2 monofucosylated structures. Antibodies directed toward types 1, 3, and 4 ABH-, X- and Lewis-related antigenic determinants were always negative because the small amounts of ABH and Lewis antigens adsorbed from the serum could not be detected by these techniques. The presence of the type 2 ABH antigens on intrinsic glycoproteins was controlled by the H gene. This correlates with the presence of alpha 2-L- fucosyltransferase and the absence of alpha 3-L-fucosyltransferase on platelets. In contrast, ABH antigens were not detected by immunofluorescence on normal peripheral lymphocytes. These cells thus have only the small amounts of antigens adsorbed from the serum, these being under control of the secretor and Lewis genes. This correlates with the absence of alpha 2-L-fucosyltransferase on lymphocytes. When lymphocytes were transformed in vitro by the Epstein-Barr virus (EBV), however, they strongly expressed the X and sialylated X antigens, which are specific markers of normal granulocytes and monocytes, respectively. Treatment of EBV-transformed lymphoblastoid cell lines with 12-O-tetradecanoylphorbol-13-O-acetate significantly decreased the expression of X and sialylated X antigens along with that of surface immunoglobulins, whereas it induced a significant expression of the H antigen under control of the H gene.

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Karpova, Olga, Nikolai Nikitin, Sergey Chirkov, Ekaterina Trifonova, Anna Sheveleva, Ekaterina Lazareva, and Joseph Atabekov. "Immunogenic compositions assembled from tobacco mosaic virus-generated spherical particle platforms and foreign antigens." Journal of General Virology 93, no. 2 (February 1, 2012): 400–407. http://dx.doi.org/10.1099/vir.0.036293-0.

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We reported recently that RNA-free spherical particles (SPs) generated by thermal remodelling of tobacco mosaic virus (TMV) are capable of binding GFP to their surface. Here, we show that SPs represent a universal particle platform that can form compositions by binding a diversity of various foreign proteins/epitopes of viral and non-viral origin to their surface. Numerous molecules of a foreign protein linked to the SP surface were revealed by immunogold electron microscopy. Several SP-based compositions were obtained containing one of the following foreign antigens: antigenic determinant A of rubella virus E1 glycoprotein; a recombinant protein containing the M2e epitope of influenza virus A protein M2; a recombinant antigen consisting of three epitopes of influenza virus A haemagglutinin; potato virus X (PVX) coat protein (CP); BSA; and PVX CP fused with the epitope of plum pox virus CP. The ‘mixed’ compositions could be also assembled by binding two different foreign antigens to each of the SPs. Immunogenicity of foreign antigens adsorbed or linked covalently to SPs in the SP-based compositions was examined. The antigenic specificity of foreign antigens was retained, whereas their immunogenicity increased significantly. It was inferred that SPs exhibit immunopotentiating activity, in particular in the form of compositions comprising SP and foreign antigen linked covalently to their surface by formaldehyde.

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Li, Dongdong, Mengjie Xu, Gaotian Li, Yu Zheng, Yong Zhang, Dandan Xia, Shaoning Wang, and Yan Chen. "Mg/Al-LDH as a nano-adjuvant for pertussis vaccine: a evaluation compared with aluminum hydroxide adjuvant." Nanotechnology 33, no. 23 (March 17, 2022): 235102. http://dx.doi.org/10.1088/1361-6528/ac56f3.

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Abstract Background. Layered double hydroxide (LDH) has been demonstrated as a highly efficient antigen platform to induce effective and durable immune response. However, whether LDH nanoparticles could act as an adjuvant for pertussis vaccines is still unknown. Here we evaluated the potential of Mg/Al-LDH as a nano-adjuvant to improve immune response against pertussis and compared it with commercial aluminum hydroxide (AH) adjuvant. Method. The Mg/Al-LDH nanoparticles were synthesized by a hydrothermal reaction. The morphology, structure and size of Mg/Al-LDH were characterized by transmission electron microscope, x-ray diffraction and MALVERN particle analysis. The ovalbumin and Pertussis toxin (PTd) was adsorbed to Mg/Al-LDH. The immune response of antigen-LDH complex was evaluated in mice, compared with commercial adjuvant alum. Hematoxylin-eosin staining was used to evaluate the inflammatory response at injection site. Results. The synthetic Mg/Al-LDH nanoparticles showed a typical hexagonal lamellar structure. The average size of synthetic nanoparticles was 102.9 nm with PDI of 0.13 and zeta potential was 44.4 mV. Mg/Al-LDH nanoparticles effectively adsorbed protein antigen and mediated antigen uptake by DC cells. Animal experiments showed that Mg/Al-LDH gave enhancement in anti-pertussis toxin (PTd) humoral immune response, which was considerable to commercial AH adjuvant. Finally, Mg/Al-LDH produced a slighter inflammatory response than AH at injection site and this injury was quickly recovered. Conclusion. Our study demonstrated the potential of Mg/Al-LDH as an effective adjuvant for pertussis vaccine, which induced comparable antibody response and had a better safety compared with commercial AH adjuvant.

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Alexander, R. J. "Immunological Evidence for Prothrombin in Human Platelets." Thrombosis and Haemostasis 55, no. 02 (1986): 268–70. http://dx.doi.org/10.1055/s-0038-1661534.

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SummaryAn attempt was made to isolate from plasma the platelet surface substrate for thrombin, glycoprotein V (GPV), because a GPV antigen was reported to be present in plasma (3). Plasma fractionation based on procedures for purification of GPV from platelets revealed a thrombin-sensitive protein with appropriate electrophoretic mobility. The protein was purified; an antiserum against it i) reacted with detergent-solubilized platelet proteins or secreted proteins in a double diffusion assay, ii) adsorbed a protein from the supernatant solution of activated platelets, and iii) inhibited thrombin-induced platelet activation, but the antiserum did not adsorb labeled GPV. The purified protein was immunochemically related to prothrombin rather than to GPV. Other antibodies against prothrombin were also able to adsorb a protein from platelets. It is concluded that 1) plasma does not contain appreciable amounts of GPV, and 2) platelets contain prothrombin or an immunochemically similar protein.

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Tsuruta, Lilian Rumi, Ana Maria Moro, Denise V. Tambourgi, and Osvaldo Augusto Sant’Anna. "Oral Tolerance Induction by Bothrops jararaca Venom in a Murine Model and Cross-Reactivity with Toxins of Other Snake Venoms." Toxins 13, no. 12 (December 3, 2021): 865. http://dx.doi.org/10.3390/toxins13120865.

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Oral tolerance is defined as a specific suppression of cellular and humoral immune responses to a particular antigen through prior oral administration of an antigen. It has unique immunological importance since it is a natural and continuous event driven by external antigens. It is characterized by low levels of IgG in the serum of animals after immunization with the antigen. There is no report of induction of oral tolerance to Bothrops jararaca venom. Here, we induced oral tolerance to B. jararaca venom in BALB/c mice and evaluated the specific tolerance and cross-reactivity with the toxins of other Bothrops species after immunization with the snake venoms adsorbed to/encapsulated in nanostructured SBA-15 silica. Animals that received a high dose of B. jararaca venom (1.8 mg) orally responded by showing antibody titers similar to those of immunized animals. On the other hand, mice tolerized orally with three doses of 1 µg of B. jararaca venom showed low antibody titers. In animals that received a low dose of B. jararaca venom and were immunized with B. atrox or B. jararacussu venom, tolerance was null or only partial. Immunoblot analysis against the venom of different Bothrops species provided details about the main tolerogenic epitopes and clearly showed a difference compared to antiserum of immunized animals.

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Freitas, Natália Erdens Maron, Emily Ferreira Santos, Leonardo Maia Leony, Ângelo Antônio Oliveira Silva, Ramona Tavares Daltro, Larissa de Carvalho Medrado Vasconcelos, Gabriela Agra Duarte, et al. "Double-antigen sandwich ELISA based on chimeric antigens for detection of antibodies to Trypanosoma cruzi in human sera." PLOS Neglected Tropical Diseases 16, no. 3 (March 11, 2022): e0010290. http://dx.doi.org/10.1371/journal.pntd.0010290.

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Background Enzyme-linked immunosorbent assays (ELISA) are generally the chosen test for Chagas disease (CD) diagnosis; however, its performance depends on the antigen preparation adsorbed to the solid phase, which may lead to false-positive results and cross-reactions. The use of chimeric recombinant antigens can overcome this limitation. Four chimeric antigens from Trypanosoma cruzi (IBMP-8.1, IBMP-8.2, IBMP-8.3 and IBMP-8.4) were developed and evaluated in phase I, II and III studies using indirect ELISA as diagnostic platform. However, peroxidase-labeled secondary anti-human IgG antibody, which is employed in indirect ELISAs, limits its use for the detection of species-specific and class-specific antibodies. To overcome this limitation, peroxidase-labeled antigens can be utilized, diagnosing both acute or chronic infection, in a species and immunoglobulin class-independent manner, through the use of a double-antigen sandwich ELISA (DAgS-ELISA). We aimed to evaluate and validate the diagnostic performance of the chimeric antigens IBMP-8.1, IBMP-8.2, IBMP-8.3 and IBMP-8.4 in the DAgS-ELISA platform. Methodology/Principal findings DAgS-ELISA was optimized by checkerboard titration. In phase I study, 207 positive and 205 negative samples were evaluated. Cross-reactivity to other infections was also assessed using 68 samples. The selected conditions for the tests utilized 25 ng of antigen per well and the conjugate diluted at 1:2,000 for all molecules. In the phase I study, the areas under the curve of IBMP-8.1, IBMP-8.2, IBMP-8.3 and IBMP-8.4 were 98.7%, 99.5%, 98.6% and 98.8%, respectively. Among the positive samples, IBMP-8.1 antigen classified 53 (25.6%) as false negative, IBMP-8.2, 27 (13%), IBMP-8.3, 24 (11.6%) and IBMP-8.4, 43 (20.8%), giving sensitivities of 74.4%, 87%, 88.4% and 79.2%, respectively. The only antigen that did not reach 100% specificity was IBMP-8.3, with 96.6%. IBMP-8.3 was also the only molecule to show cross-reactivity with HTLV. Conclusions/Significance DAgS-ELISA is a promising tool for immunodiagnosis, and despite the high AUC values, the performance of this assay was different from the values obtained by our group when using these antigens in the indirect ELISA, for this reason, improvements are being considered to increase the sensitivity of the DAgS-ELISA.

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Dierks, S. E., J. E. Butler, and H. B. Richerson. "Altered recognition of surface-adsorbed compared to antigen-bound antibodies in the ELISA." Molecular Immunology 23, no. 4 (April 1986): 403–11. http://dx.doi.org/10.1016/0161-5890(86)90138-0.

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Pérez-Betancourt, Yunys, Péricles Marques Araujo, Bianca de Carvalho Lins Fernandes Távora, Daniele Rodrigues Pereira, Eliana Lima Faquim-Mauro, and Ana Maria Carmona-Ribeiro. "Cationic and Biocompatible Polymer/Lipid Nanoparticles as Immunoadjuvants." Pharmaceutics 13, no. 11 (November 4, 2021): 1859. http://dx.doi.org/10.3390/pharmaceutics13111859.

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Nanostructures have been of paramount importance for developing immunoadjuvants. They must be cationic and non-cytotoxic, easily assembling with usually oppositely charged antigens such as proteins, haptens or nucleic acids for use in vaccines. We obtained optimal hybrid nanoparticles (NPs) from the biocompatible polymer poly(methyl methacrylate) (PMMA) and the cationic lipid dioctadecyl dimethyl ammonium bromide (DODAB) by emulsion polymerization of methyl methacrylate (MMA) in the presence of DODAB. NPs adsorbed ovalbumin (OVA) as a model antigen and we determined their adjuvant properties. Interestingly, they elicited high double immune responses of the cellular and humoral types overcoming the poor biocompatibility of DODAB-based adjuvants of the bilayer type. The results suggested that the novel adjuvant would be possibly of use in a variety of vaccines.

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Hernandez-Franco, Juan F., Imran M. Jan, Malaycia Goldsmith, and Harm HogenEsch. "Optimizing vaccine performance through improved cross-presentation with a nanoparticle adjuvant." Journal of Immunology 208, no. 1_Supplement (May 1, 2022): 123.03. http://dx.doi.org/10.4049/jimmunol.208.supp.123.03.

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Abstract Activation of CD8 T cells requires presentation of antigenic peptides by MHC I molecules and costimulatory signals provided by CD80 and CD86 on dendritic cells (DCs). Subunit and purified antigen vaccines often fail to induce CD8 T cell responses because the antigens have limited access to the endogenous MHC I pathway, a phenomenon known as antigen cross-presentation. Vaccine adjuvants are being investigated to promote cross-presentation, but adjuvants in currently licensed vaccines are not effective. The goal of this study was to determine if a combination adjuvant (NanoS100) comprised of cationic plant-derived adjuvant nanoparticles (Nano-11) and the synthetic STING agonist ADU-S100 stimulates cross-presentation in vitro and in vivo after intradermal and intranasal vaccination. Incubation of DCs with OVA adsorbed to NanoS100 significantly enhanced the presentation of antigen to the MHC I-restricted OVA-specific B3Z T cell hybridoma compared with OVA only. The cross-presentation was inhibited by preincubation of DCs with chlorpromazine and chloroquine, suggesting that NanoS100 supports endosomal processing of OVA. NanoS100 also significantly increased the expression of CD80 and CD86 on antigen-presenting cells in vitro. Vaccination of mice with OVA and NanoS100 increased humoral and cellular responses with a significant increase of IFNγ+ CD8 T cells in the spleen and the lungs. Intranasal immunization induced a greater percentage of IFNγ+ CD8 T cells in the lungs compared with intradermal immunization. These findings support the potential utility of NanoS100 as a vaccine adjuvant.

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Wui, Seo Ri, Ara Ko, Ji In Ryu, Eojin Sim, Soo Jeong Lim, Shin Ae Park, Kwang Sung Kim, Ha Kim, Hyewon Youn, and Na Gyong Lee. "The Effect of a TLR4 Agonist/Cationic Liposome Adjuvant on Varicella-Zoster Virus Glycoprotein E Vaccine Efficacy: Antigen Presentation, Uptake, and Delivery to Lymph Nodes." Pharmaceutics 13, no. 3 (March 15, 2021): 390. http://dx.doi.org/10.3390/pharmaceutics13030390.

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Adjuvant CIA09, composed of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP)-based cationic liposomes and the toll-like receptor 4 agonist de-O-acylated lipooligosaccharide (dLOS), has been shown to enhance antibody and cellular immune responses to varicella-zoster virus (VZV) glycoprotein E (gE), recombinant tuberculosis vaccine antigen, and inactivated Japanese encephalitis vaccine. In this study, we investigated its modes of action using VZV gE as a model antigen. Liposomes adsorbed gE and cooperatively with dLOS promoted endocytosis-mediated cellular uptake of gE by mouse dendritic cells in vitro. CIA09 increased the stability and cellular uptake of the antigen at the muscle site of injection, and induced immune cell recruitment and cytokine and chemokine production, which led to efficient antigen delivery to draining lymph nodes. Mouse bone marrow-derived dendritic cells, pulsed with CIA09-adjuvanted gE, efficiently presented gE to antigen-specific T cells, inducing Th1-type biased immunity, as shown by high IFN-γ production. The data indicate that liposomes and dLOS cooperate in the adjuvant activity of CIA09 by promoting antigen uptake and delivery to lymph nodes as well as antigen presentation to T cells.

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Ovsyannikova, Inna G., V. Shane Pankratz, Robert A. Vierkant, Nicholas M. Pajewski, Conrad P. Quinn, Richard A. Kaslow, Robert M. Jacobson, and Gregory A. Poland. "Human Leukocyte Antigens and Cellular Immune Responses to Anthrax Vaccine Adsorbed." Infection and Immunity 81, no. 7 (May 6, 2013): 2584–91. http://dx.doi.org/10.1128/iai.00269-13.

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ABSTRACTInterindividual variations in vaccine-induced immune responses are in part due to host genetic polymorphisms in the human leukocyte antigen (HLA) and other gene families. This study examined associations between HLA genotypes, haplotypes, and homozygosity and protective antigen (PA)-specific cellular immune responses in healthy subjects following immunization with Anthrax Vaccine Adsorbed (AVA). While limited associations were observed between individual HLA alleles or haplotypes and variable lymphocyte proliferative (LP) responses to AVA, analyses of homozygosity supported the hypothesis of a “heterozygote advantage.” Individuals who were homozygous for any HLA locus demonstrated significantly lower PA-specific LP than subjects who were heterozygous at all eight loci (median stimulation indices [SI], 1.84 versus 2.95,P= 0.009). Similarly, we found that class I (HLA-A) and class II (HLA-DQA1 and HLA-DQB1) homozygosity was significantly associated with an overall decrease in LP compared with heterozygosity at those three loci. Specifically, individuals who were homozygous at these loci had significantly lower PA-specific LP than subjects heterozygous for HLA-A (median SI, 1.48 versus 2.13,P= 0.005), HLA-DQA1 (median SI, 1.75 versus 2.11,P= 0.007), and HLA-DQB1 (median SI, 1.48 versus 2.13,P= 0.002) loci, respectively. Finally, homozygosity at an increasing number (≥4) of HLA loci was significantly correlated with a reduction in LP response (P< 0.001) in a dose-dependent manner. Additional studies are needed to reproduce these findings and determine whether HLA-heterozygous individuals generate stronger cellular immune response to other virulence factors (Bacillus anthracisLF and EF) than HLA-homozygous subjects.

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Skare, Jonathan T., Denise M. Foley, Santiago R. Hernandez, Deanna C. Moore, David R. Blanco, James N. Miller, and Michael A. Lovett. "Cloning and Molecular Characterization of Plasmid-Encoded Antigens of Borrelia burgdorferi." Infection and Immunity 67, no. 9 (September 1, 1999): 4407–17. http://dx.doi.org/10.1128/iai.67.9.4407-4417.1999.

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ABSTRACT Thirteen independent clones that encode Borrelia burgdorferi antigens utilizing antiserum from infection-immune rabbits were identified. The serum was adsorbed against noninfectiousB. burgdorferi B31 to enrich for antibodies directed against either infection-associated antigens of B. burgdorferi B31 or proteins preferentially expressed during mammalian infection. The adsorption efficiency of the immune rabbit serum (IRS) was assessed by Western immunoblot analysis with protein lysates derived from infectious and noninfectious B. burgdorferi B31. The adsorbed IRS was used to screen a B. burgdorferi expression library to identify immunoreactive phage clones. Clones were then expressed in Escherichia coli and subsequently analyzed by Western blotting to determine the molecular mass of the recombinant B. burgdorferi antigens. Southern blot analysis of the 13 clones indicated that 10 contained sequences unique to infectious B. burgdorferi. Nucleotide sequence analysis indicated that the 13 clones were composed of 9 distinct genetic loci and that all of the genes identified were plasmid encoded. Five of the clones carried B. burgdorferi genes previously identified, including those encoding decorin binding proteins A and B (dbpAB), a rev homologue present on the 9-kb circular plasmid (cp9), a rev homologue from the 32-kb circular plasmid (cp32-6), erpM, and erpX. Additionally, four previously uncharacterized loci with no known homologues were identified. One of these unique clones encoded a 451-amino-acid lipoprotein with 21 consecutive, invariant 9-amino-acid repeats near the amino terminus that we have designated VraA (for “virulent strain-associated repetitive antigen A”). Since all the antigens identified are recognized by serum from infection immune rabbits, these antigens represent potential vaccine candidates and, based on the identification of dbpAB in this screen, may also be involved in pathogenic processes operative in Lyme borreliosis.

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Williamson, E. D., I. Hodgson, N. J. Walker, A. W. Topping, M. G. Duchars, J. M. Mott, J. Estep, et al. "Immunogenicity of Recombinant Protective Antigen and Efficacy against Aerosol Challenge with Anthrax." Infection and Immunity 73, no. 9 (September 2005): 5978–87. http://dx.doi.org/10.1128/iai.73.9.5978-5987.2005.

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ABSTRACT Immunization with a recombinant form of the protective antigen (rPA) from Bacillus anthracis has been carried out with rhesus macaques. Rhesus macaques immunized with 25 μg or more of B. subtilis-expressed rPA bound to alhydrogel had a significantly increased immunoglobulin G (IgG) response to rPA compared with macaques receiving the existing licensed vaccine from the United Kingdom (anthrax vaccine precipitated [AVP]), although the isotype profile was unchanged, with bias towards the IgG1 and IgG2 subclasses. Immune macaque sera from all immunized groups contained toxin-neutralizing antibody and recognized all the domains of PA. While the recognition of the N terminus of PA (domains 1 to 3) was predominant in macaques immunized with the existing vaccines (AVP and the U.S. vaccine anthrax vaccine adsorbed), macaques immunized with rPA recognized the N- and C-terminal domains of PA. Antiserum derived from immunized macaques protected macrophages in vitro against the cytotoxic effects of lethal toxin. Passive transfer of IgG purified from immune macaque serum into naive A/J mice conferred protection against challenge with B. anthracis in a dose-related manner. The protection conferred by passive transfer of 500 μg macaque IgG correlated significantly (P = 0.003; r = 0.4) with the titers of neutralizing antibody in donor macaques. Subsequently, a separate group of rhesus macaques immunized with 50 μg of Escherichia coli-derived rPA adsorbed to alhydrogel was fully protected against a target dose of 200 50% lethal doses of aerosolized B. anthracis. These data provide some preliminary evidence for the existence of immune correlates of protection against anthrax infection in rhesus macaques immunized with rPA.

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Wagner, Leslie, Anita Verma, Bruce D. Meade, Karine Reiter, David L. Narum, Rebecca A. Brady, Stephen F. Little, and Drusilla L. Burns. "Structural and Immunological Analysis of Anthrax Recombinant Protective Antigen Adsorbed to Aluminum Hydroxide Adjuvant." Clinical and Vaccine Immunology 19, no. 9 (July 18, 2012): 1465–73. http://dx.doi.org/10.1128/cvi.00174-12.

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ABSTRACTNew anthrax vaccines currently under development are based on recombinant protective antigen (rPA) and formulated with aluminum adjuvant. Because long-term stability is a desired characteristic of these vaccines, an understanding of the effects of adsorption to aluminum adjuvants on the structure of rPA is important. Using both biophysical and immunological techniques, we compared the structure and immunogenicity of freshly prepared rPA-Alhydrogel formulations to that of formulations stored for 3 weeks at either room temperature or 37°C in order to assess the changes in rPA structure that might occur upon long-term storage on aluminum adjuvant. Intrinsic fluorescence emission spectra of tryptophan residues indicated that some tertiary structure alterations of rPA occurred during storage on Alhydrogel. Using anti-PA monoclonal antibodies to probe specific regions of the adsorbed rPA molecule, we found that two monoclonal antibodies that recognize epitopes located in domain 1 of PA exhibited greater reactivity to the stored formulations than to freshly prepared formulations. Immunogenicity of rPA-Alhydrogel formulations in mice was assessed by measuring the induction of toxin-neutralizing antibodies, as well as antibodies reactive to 12-mer peptides spanning the length of PA. Mice immunized with freshly prepared formulations developed significantly higher toxin-neutralizing antibody titers than mice immunized with the stored preparations. In contrast, sera from mice immunized with stored preparations exhibited increased reactivity to nine 12-mer peptides corresponding to sequences located throughout the rPA molecule. These results demonstrate that storage of rPA-Alhydrogel formulations can lead to structural alteration of the protein and loss of the ability to elicit toxin-neutralizing antibodies.

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Kimura, E., Makoto Itoh, Xu-Guang Qiu, Nipul K. Gunawardena, and Mirani V. Weerasooriya. "Filter paper-adsorbed whole blood for Og4C3 antigen capture elisa and its field application." Parasitology International 47 (August 1998): 45. http://dx.doi.org/10.1016/s1383-5769(98)80074-3.

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Amini, Yousef, Bagher Moradi, Mohsen Tafaghodi, Zahra Meshkat, Kiarash Ghazvini, and Mahdi Fasihi-Ramandi. "TB trifusion antigen adsorbed on calcium phosphate nanoparticles stimulates strong cellular immunity in mice." Biotechnology and Bioprocess Engineering 21, no. 5 (September 2016): 653–58. http://dx.doi.org/10.1007/s12257-016-0326-y.

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Li, Bei, Yafang Tan, Jingyu Guo, Baizhong Cui, Zuyun Wang, Hu Wang, Lei Zhou, et al. "Use of protein microarray to identify gene expression changes ofYersinia pestisat different temperatures." Canadian Journal of Microbiology 57, no. 4 (April 2011): 287–94. http://dx.doi.org/10.1139/w11-007.

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Yersinia pestis is a bacterium that is transmitted between fleas, which have a body temperature of 26 °C, and mammalian hosts, which have a body temperature of 37 °C. To adapt to the temperature shift, phenotype variations, including virulence, occur. In this study, an antigen microarray including 218 proteins of Y. pestis was used to evaluate antibody responses in a pooled plague serum that was unadsorbed, adsorbed by Y. pestis cultivated at 26 °C, or adsorbed by Y. pestis cultivated at 26 and 37 °C to identify protein expression changes during the temperature shift. We identified 12 proteins as being expressed at 37 °C but not at 26 °C, or expressed at significantly higher levels at 37 °C than at 26 °C. The antibodies against 7 proteins in the serum adsorbed by Y. pestis cultivated at 26 and 37 °C remained positive, suggesting that they were not expressed on the surface of Y. pestis in LB broth in vitro or specifically expressed in vivo. This study proved that protein microarray and antibody profiling comprise a promising technique for monitoring gene expression at the protein level and for better understanding pathogenicity, to find new vaccine targets against plague.

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Mi, Fwu-Long, Shin-Shing Shyu, Chin-Ta Chen, and Jen-Yu Schoung. "Porous chitosan microsphere for controlling the antigen release of Newcastle disease vaccine: preparation of antigen-adsorbed microsphere and in vitro release." Biomaterials 20, no. 17 (September 1999): 1603–12. http://dx.doi.org/10.1016/s0142-9612(99)00064-2.

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Skoble, Justin, John W. Beaber, Yi Gao, Julie A. Lovchik, Laurie E. Sower, Weiqun Liu, William Luckett, et al. "Killed but Metabolically Active Bacillus anthracis Vaccines Induce Broad and Protective Immunity against Anthrax." Infection and Immunity 77, no. 4 (January 21, 2009): 1649–63. http://dx.doi.org/10.1128/iai.00530-08.

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ABSTRACTBacillus anthracisis the causative agent of anthrax. We have developed a novel whole-bacterial-cell anthrax vaccine utilizingB. anthracisthat is killed but metabolically active (KBMA). Vaccine strains that are asporogenic and nucleotide excision repair deficient were engineered by deleting thespoIIEanduvrABgenes, renderingB. anthracisextremely sensitive to photochemical inactivation with S-59 psoralen and UV light. We also introduced point mutations into thelefandcyagenes, which allowed inactive but immunogenic toxins to be produced. Photochemically inactivated vaccine strains maintained a high degree of metabolic activity and secreted protective antigen (PA), lethal factor, and edema factor. KBMAB. anthracisvaccines were avirulent in mice and induced less injection site inflammation than recombinant PA adsorbed to aluminum hydroxide gel. KBMAB. anthracis-vaccinated animals produced antibodies against numerous anthrax antigens, including high levels of anti-PA and toxin-neutralizing antibodies. Vaccination with KBMAB. anthracisfully protected mice against challenge with lethal doses of toxinogenic unencapsulated Sterne 7702 spores and rabbits against challenge with lethal pneumonic doses of fully virulent Ames strain spores. Guinea pigs vaccinated with KBMAB. anthraciswere partially protected against lethal Ames spore challenge, which was comparable to vaccination with the licensed vaccine anthrax vaccine adsorbed. These data demonstrate that KBMA anthrax vaccines are well tolerated and elicit potent protective immune responses. The use of KBMA vaccines may be broadly applicable to bacterial pathogens, especially those for which the correlates of protective immunity are unknown.

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Vitral, Claudia Lamarca, Ana Maria Coimbra Gaspar, and Clara Fumiko Tachibana Yoshida. "Two competitive enzyme immunoassays for the detection of IgG class antibodies to hepatitis a antigen." Revista da Sociedade Brasileira de Medicina Tropical 24, no. 2 (June 1991): 79–85. http://dx.doi.org/10.1590/s0037-86821991000200003.

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Two competitive enzyme immunoassays (EIA) techniques were developed: in the first (COMP-1), test sera were added together with HAV antigen on anti-HAV IgG-coated wells followed by an anti-HA VHRP conjugate; in the second (COMP-2), test sera and anti-HA VHRP conjugate competed for HAV epitopes previously adsorbed to anti-HA V IgG-coated wells. Both procedures used tetramethylbenzidine (TMB) as a substrate. Both competitive tests were shown to be reproducible and suitable for routine diagnosis and research purposes.

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Journal articles on the topic 'Adsorbed antigen'

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