Dissertations / Theses on the topic 'Immunological adjuvants'

Thesis (Ph. D.)--Biomedical Engineering, Georgia Institute of Technology, 2006.
Babensee, Julia, Committee Chair ; Andres Garcia, Committee Member ; Mary Marovich, Committee Member ; Barbara Boyan, Committee Member ; Elliot Chaikof, Committee Member ; Cheng Zhu, Committee Member.

Coelomocyte migration responses, both random and chemotatic, were examined in the earthworm Lumbricus terrestris. Coelomocyte random migration patterns towards non-stimulatory, non-chemotatic solutions were described. Migration responses to immunostimulatory agents lipopolysaccharides (LPS), N-formly-methionyl-leucyl-phenylalanine (FMLP), sheep erythrocytes, Saccharomyces cerevisiae, Aeromonas hydrophila, Eisenia fetida and Rhabditis pellio were characterized. Chemotaxis was reported to LPS, FMLP, sheep erythrocytes, S. cerivesae and E. fetida. Bio-indicator potential of chemotaxis is discussed relative to variability in migration responses.

As vacinas pertussis celulares apresentam certa reatogenicidade e as acelulares, menos reatogênicas, têm seu uso restrito, devido a seu alto custo. O Instituto Butantan desenvolveu uma vacina pertussis celular (Plow), com baixo teor de lipopolissacarídeo e outra acelular (Pa), por metodologia simples e econômica. Essas preparações, combinadas aos toxóides diftérico e tetânico (DTPlow e DTPa, respectivamente), foram comparadas à DTP tradicional, com diferentes adjuvantes: vitamina A, surfactante pulmonar, BCG, monofosforil lipídeo A (MPL) e Al(OH)3. A resposta humoral em camundongos foi semelhante para as diferentes formulações e independente do adjuvante utilizado. As vacinas induziram níveis equilibrados de IgG1/IgG2a anti-pertussis e a DTPlow mostrou-se menos reatogênica, induzindo níveis significativamente menores de IL-6 sérica. A adição de MPL sugeriu tendência de proteção contra a colonização nasotraqueal no grupo imunizado com DTPa e levou à indução de IFN-g nos grupos imunizados com DTP e DTPa, sugerindo possível atividade imunomodulatória para Th1.
The whole cell pertussis vaccines present some reactogenicity and the acellular, less reactogenic, have prohibitive use due to its high cost. Instituto Butantan developed a less reactogenic whole cell pertussis vaccine (Plow), with low lipopolysaccharide content and an acellular vaccine (Pa), by simple and economic methodology. These preparations, combined to diphtheria and tetanus toxoids (DTPlow and DTPa, respectively), were compared with the traditional DTP, with different adjuvants: vitamin A, pulmonary surfactant, BCG, monophosphoryl lipid A (MPL) and Al(OH)3. The humoral immune response induced in mice by the different vaccine formulations, was similar and independent of the adjuvant used. The vaccines induced balanced levels of IgG1/IgG2a anti-pertussis and DTPlow showed to be less rectogenic, inducing lower levels of serum IL-6. The use of MPL suggested to induce higher protection against nasotracheal colonization in DTPa group and induced IFN-g in the DTP and DTPa groups, suggesting a possible immunemodulatory activity for Th1.

Aim: Subunit vaccines have received increasing attention due to their good safety profile. However, subunit vaccines feature low immunogenicity, and soluble antigen is largely ignored by the immune system due to its lack of danger signals. To stimulate an appropriate immune response, subunit antigen vaccines require the addition of an adjuvant and multiple administrations. This study aimed to formulate biodegradable lipid implants, containing a suitable adjuvant, which delivers antigen in a sustained manner. The physico-chemical characteristics of the implants and their ability to stimulate immune responses towards a model antigen in vivo were investigated. Methods: Lipid implants were prepared from phospholipid and cholesterol. Different adjuvants were added, and their potential to induce an immune response to the model antigen ovalbumin (OVA) was investigated. The adjuvants and immunomodulators assessed were Quil-A (QA), imiquimod, and an α-Galactosylceramide (α-GalCer) analogue. Liposomal dispersions were prepared using the lipid film hydration method. These were freeze-dried, and the powder compressed into matrices (diameter of 2 mm). Physico-chemical characterisation was undertaken by transmission electron microscopy (TEM) to investigate the release of colloidal structures (liposomes, immunostimulating complexes [ISCOMs]) upon hydration with release media. Surface changes of the implant matrices were analysed using scanning electron microscopy (SEM). The release of the fluorescently-labelled antigen ovalbumin (FITC-OVA) and its entrapment into the colloidal particles was investigated using spectrofluorophotometry. Additionally, incorporation of the cationic cholesterol derivative DC-cholesterol (DCCHOL) into implants to allow for charge-charge interactions with the negatively-charged OVA, and replacement of the phospholipid with a phospholipid having a higher transition temperature to facilitate the manufacturing process, were attempted and assessed. The immune response stimulated towards OVA released from the implants was analysed in vivo using a C57Bl/6 mouse model. Expansion of CD8⁺ T cells and CD8 T cells specific for the CD8 epitope of OVA (SIINFEKL), as well as expansion of CD4⁺ T cells, were assessed. The ability of implants to stimulate T cell proliferation and interferon-γ production after in vitro restimulation with OVA was analysed. Serum samples were analysed for OVA-specific IgG antibodies. Results: Lipid implants containing Quil-A released colloidal structures upon hydration with buffer. The type of colloids observed by TEM depended on the ratio of QA:cholesterol:phospholipid. Release of OVA was sustained over ten days in implants prepared with egg yolk PC. However, the release kinetics depended strongly on the choice of phospholipid. In vivo, lipid implants containing Quil-A evoked expansion of CD8⁺ T cells. The immune response to one implant was comparable to that obtained by two equivalent injection immunisations. Therefore, the implants obviated the need for multiple immunisations in the vaccination regime tested here. Expansion of CD8⁺ T cells towards the Quil-A-containing implant was greater than that achieved by the immunomodulators imiquimod and the α-GalCer analogue. Quil-A-containing implants produced OVA-specific IgG antibodies to a greater extent than the implants containing imiquimod or α-GalCer. Incorporation of the cationic DCCHOL did not increase the entrapment efficiency of OVA into liposomes. However, the in vivo investigation of DCCHOL-containirig implants showed an adjuvant effect of DCCHOL on antibody responses, but not on cell-mediated immunity. Conclusion: Lipid implants offer great potential as sustained release vaccine delivery systems. The lipid components in the implant formulation were well-tolerated and biodegradable. Lipid implants combine the advantages of sustained release of antigen and particulate delivery by the formation of colloidal particles.

Peptídeos de defesa do hospedeiro antimicrobiano (PDHA) são componentes do sistema imune inato podem ser expressos constitutivamente ou induzidos por componentes bacterianos, citocinas, ou a combinação de ambos. Estes peptídeos possuem ação direta sobre microrganismo e são potentes imunomoduladores de células de mamíferos. A microplusina é um peptídeo antimicrobiano quelante de cobre, originário do aracnídeo Tick Rhipicephalus (Boophilus) microplus, com massa molecular de 10 204 Da. Este peptídeo possue atividade bacteriostática sobre Micrococcus luteus, mas sem atividade microbicida sobre E. coli e Candida albicans. Neste trabalho foi analisado o efeito direto da microplusina em cultura de macrófagos derivados de medula óssea (MDM) tratados ou não com LPS ou IFN-γ. Foi demonstrado que este peptídeo não teve efeito citotóxico para macrófagos, não estimulou a síntese de NO e IL-1β, mas aumentou a produção de TNF-α e IL-6 após estímulo. O pré-tratamento dos macrófagos com microplusina, antes da adição do LPS, não modificou o nível de nitrito, TNF-α ou IL-6 em resposta ao LPS. Quando os macrófagos foram pré-tratados com microplusina e posteriormente incubados com IFN-γ houve aumento significativo da produção de NO e TNF-α, confirmando a natureza pró-inflamatória deste peptídeo. Isto indica que a microplusina é um agente imunomodulador da resposta imune inata e pode auxiliar no controle de infecções por microrganismos patogênicos.
Antimicrobial host defense peptides are components of the innate immune system. They are expressed constitutively or induced by bacterial components, cytokines or the combination of both are expressed constitutively or induced by bacterial components, cytokines, or a combination of both. These peptides have direct action on microorganisms and are potent immunomodulators in mammalian cells. Microplusin is a copper II-chelating antimicrobial peptide from the Tick Rhipicephalus ( Boophilus) microplus, with a molecular mass of 10 204 Da. This peptide has a bacteriostatic activity against Micrococcus luteus, but no activity against E. coli and Candida albicans. The aim of the present work was to analyze the direct effect of microplusin in the culture of murine bone marrow derivated macrophages (BDM) treated or not with LPS or IFN-γ. Our data showed that microplusin had no cytotoxic effect on macrophages, did not stimulate the synthesis of NO and IL-1β, but increased the production of TNF-α and IL-6 after stimulation. The pre-treatment of macrophages with microplusin before LPS addition did not change the level of nitrite, TNF-α or IL-6 in response to LPS. If the microplusin pre-treated macrophages were incubated with IFN-γ there was evidence that microplusin led to significant increase of NO and TNF-α production confirming the pro-inflammatory characteristic of microplusin and its potential against pathogenic microorganisms. This indicates microplusin to be a potential immunomodulating agent of innate immunity and may help to control infections by pathogenic microorganisms.

Toxinas termo-lábeis expressas por Escherichia coli enterotoxigênica (LT-I, LT-IIa e LT-IIb) são adjuvantes sistêmicos e de mucosa. Essas proteínas apresentam reduzida identidade (<14%) em suas subunidades B e ligação a receptores distintos, o que pode resultar em propriedades biológicas diferenciais. O objetivo do trabalho foi avaliar a resposta imune induzida pela toxina LT-IIa e seu pentâmero B (LT-IIaB) administradas pelas vias transcutânea e intradérmica. Inicialmente as proteínas foram expressas em E. coli, purificadas e avaliadas quanto à funcionalidade in vitro. Numa segunda etapa, as propriedades imunomoduladoras de LT-IIa e LT-IIaB, imunogenicidade e atividade adjuvante, foram avaliadas em modelo murino. A resposta imune (humoral e celular) induzida contra ovalbumina (OVA), aplicada como antígeno, foi determinada. Os resultados demonstram que as atividades adjuvantes induzidas por LT-IIa e LT-IIaB variam de acordo com a via de inoculação e que as holotoxinas LT-I e LT-IIa induzem graus de inflamação e ativação de resposta imune distintos em camundongos.
Heat-labile toxins expressed by enterotoxigenic Escherichia coli (LT-I, LT-IIa and LT-IIb) are potent systemic and mucosal adjuvants. These proteins have low identity (<14%) in their B subunits and bind to different receptors, which may result in differential biological properties. The objective of this work was to evaluate the immune response induced by LT-IIa toxin and its pentameric B subunit (LT-IIaB) delivered by transcutaneous and intradermic routes. Initially the proteins of interest were expressed in recombinant E. coli strains, purified and tested for functionality in vitro. In a second moment, the immunomodulatory properties of LT-IIa and LT-IIaB, immunogenicity and adjuvant activity, were evaluated in mouse model. The humoral and cellular immune responses induced against ovalbumin (OVA) used as antigen were determined. The results show that the adjuvant activity of LT-IIa and its B pentamer depends on the route of inoculation and that LT-I and LT-IIa differ both on induction of inflammation and activation of immune responses in mice.

A leptospirose é uma zoonose de importância global causada por espiroquetas patogênicas do gênero Leptospira. Foi avaliado o potencial adjuvante da flagelina FliCi de Salmonella enterica sorovar Thyphimurium na indução de resposta imunoprotetora em uma formulação vacinal acelular composta pela proteína LigAc e por seis prováveis lipoproteínas de membrana externa recombinantes de Leptospira interrogans sorovar Copenhageni como alternativa profilática. Grupos de hamsters imunizados com LigAc co-administrada com o pool das proteínas acrescidas de FliCi ou Al(OH)3 apresentaram altos títulos de anticorpos contra as proteínas recombinantes e foram protegidos do desafio letal (86-100%). Grupos imunizados com vacina comercial, bacterina ou pool+LigAc+FliCi apresentaram redução na colonização renal (0-28%). Dados sugerem aumento da expressão dos genes das citocinas de resposta Th1/Th2. Os resultados demonstram que novas formulações vacinais, compostas por proteínas recombinantes e flagelina FliCi como adjuvante, é um caminho promissor.
Leptospirosis is a global zoonotic disease caused by pathogenic spirochetes of the genus Leptospira. In the present study, we evaluated the adjuvant activity of Salmonella enterica FliCi flagellin in the protective immunity induced by the LigAc and also by six other novel recombinant leptospiral outer membrane lipoproteins (OMP) of Leptospira interrogans serovar Copenhageni. Immunization of hamsters with LigAc or LigAc coadministered with OMPs cocktail, both with FliCi or Al(OH)3, induced robust antibody responses against recombinant proteins, and conferred protection after challenge (86-100%). Moreover, only groups inoculated with the commercial vaccine, bacterin or LigAc coadministered with OMPs cocktail and FliCi as adjuvant showed reduced bacterial load in kidneys (0-28%) with significant enhancement of gene expression of both Th1 and Th2 cytokines. Taken together, our data pave the way for the development of novel vaccine formulations against leptospirosis, using recombinant proteins and FliCi as adjuvant.

Thesis (MSc (Biomedical Technology))--Cape Peninsula University of Technology, 2018.
The challenge of antimicrobial resistance has increased drastically over the years as more microorganisms are becoming resistant to the available conventional treatments. The burden of antimicrobial resistant infections is intensified by the increase in immunocompromising conditions such as HIV/AIDS and cancer. Due to this challenge, pharmaceutical companies, health sectors and researches are in search of new antimicrobial agents that can solve the problem at hand. Medicinal plants are a reliable source for drug discovery as it is estimated that 25% of modern medicine originated from plants. They have also been used traditionally as sources of medicine in the treatment of many human ailments. Plants can also be applied in the field of nanotechnology. Nanotechnology is a promising field in medicine as it has the potential to offer improved methods for disease diagnostics and therapeutics. The use of plants in nanotechnology brings about biologically friendly nanomaterials. Cotyledon orbiculata is one of the well-known and common plants of South Africa that is used in traditional medicinal practices. The nanotechnology applications as well as the antimicrobial and immunomodulatory effects of this plant were evaluated. The ability of C. orbiculata to synthesize silver nanoparticles was determined. Optimisation of silver nanoparticle synthesis using water extract of C. orbiculata was done at different conditions. The conditions evaluated include, reaction temperature (25 and 70°C), silver nitrate concentration (1 and 3mM), plant extract concentration (1.5, 3 and 6mg/ml) and reaction time. The synthesis of silver nanoparticles using this plant was successful. The optimal conditions for the synthesis of silver nanoparticles using C. orbiculata were 3mg/ml of the C. orbiculata extract, 3mM silver nitrate at a reaction temperature of 70°C for 2 hours. Under these conditions, spherical, crystalline nanoparticles with sizes of 20-40nm were produced. The antimicrobial and immunomodulatory properties of C. orbiculata extracts and silver nanoparticles were evaluated. Antimicrobial activity was evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Methicillin resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Candida albicans, using the micro-dilution assay to determine the minimum inhibitory concentration (MIC). The results obtained revealed that all extracts of C. orbiculata have antimicrobial properties against all the microorganisms tested. The MICs of the extracts ranged from 3.13 to 50mg/ml and the MBC/MFC from 6.25 to >100mg/ml. The methanol extract exhibited better antimicrobial activity in comparison to the others extracts whereas the water extract had better antifungal properties. The chloroform extract showed the lowest activity in both antibacterial and antifungal studies. Silver nanoparticles also exhibited antimicrobial activity against all the microorganisms tested. It’s MICs against these microorganisms ranged from 5–80μg/ml and MBC/MFC from 20-160μg/ml. The silver nanoparticles were highly active than the water extract against both the bacteria and the fungi. Immunomodulatory effects of the plant extracts and silver nanoparticles were determined by evaluating cytokine production using the enzyme linked immunoassay (ELISA) assay. All the extracts and silver nanoparticles of C. orbiculata were found to have anti-inflammatory properties. The water extracts showed more anti-inflammatory activity against the cytokines than the other extracts. However the silver nanoparticles were more active than the water extract. The findings from this study confirmed that C. orbiculata have antimicrobial and immunomodulatory effects. This provided scientific evidence of the traditional use of this plant in the treatment of skin infections and inflammatory conditions.

Este trabalho realizou importantes avanços na elucidação do potencial das toxinas termo-lábeis do tipo II (LT-IIs) como adjuvantes por via intradérmica e transcutânea. Os dados gerados indicam que LT-IIb e LT-IIc nativas atuam como potentes adjuvantes vacinais por via intradérmica induzindo respostas imunológicas antígeno específicas, como medido pela produção de anticorpos sistêmicos (IgG) e ativação de linfócitos T CD8+ citotóxicos. Soma-se ao potencial adjuvante demonstrado para as LT-IIs por essa via a baixa reatogenicidade das moléculas, com menores níveis de edema e reduzida migração leucocitária para o sítio de inoculação em comparação a LT-I. Os resultados indicam também que o efeito adjuvante das LTs aplicadas por via transcutânea pode estar relacionado à capacidade de ligação ao gangliosídeo GM1 já que a toxina LT-IIb, incapaz de interagir com este receptor, não apresenta efeito adjuvante por essa via. O conjunto de dados apresentados abre perspectivas para o emprego das LT-IIs nativas como adjuvantes parenterais em vacinas para animais e humanos.
This work has made significant advances in the understanding of the potential of type II heat-labile toxins (LT-IIs) as vaccine adjuvants by intradermal and transcutaneous route. The generated data indicate that native forms of LT-IIb and LT-IIc act as potent vaccine adjuvants when intradermally injected inducing antigen-specific immune responses, as measured by the generation of systemic serum antibody (IgG) and activation of cytotoxic CD8+ T lymphocytes. Besides the adjuvant effects, LT-IIs show reduced side effects, measured by the lesser edema formation and reduced leukocytes migration to the site of injection, in comparison to LT-I. The results also indicate that the adjuvant activity of LTs applied transcutaneously may be related to the the ganglioside GM1 binding property since the LT-IIb toxin, unable to interact with this receptor, has no adjuvant effect by this route. The presented data set opens prospects for the employment of native LT-IIs as parenteral adjuvants in vaccines for animals and humans.

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The vaccines with multiple antigens have represented a major advance in the immunization of pets and production animals, since they represent economies of time, cost, and stress. However, the efficiency of these vaccines have sometimes been questioned and the choice of an appropriate adjuvant can mean a breakthrough in multiple immunizations. In this context, propolis, which is drawing the attention of many researchers due to its bioactive properties, emerges as a possible candidate, because many studies have demonstrated its stimulating activity on the humoral and cellular immune system. As studies have shown adjuvant activity in inactivated and monovalent vaccines, but there are no reports on its action on multiple and attenuated vaccines, this study aimed at evaluating the immunomodulatory capacity of ethanolic extract of green propolis and aqueous extract of brown propolis, against attenuate parvovirus canine (CPV) and inactivated canine coronavirus (CCoV), when associated with a vaccine composed of multiple antigens. Green propolis stimulated the production of antibodies against CPV in animals inoculated with the highest concentration of antigen (3.0 x106 TCID50) co-administered with 400 mg/dose of its ethanolic extract. The addition of 400 mg/dose of aqueous extract of brown propolis to different concentrations of commercial antigens (0.75, 1.5 e 3.0 x 106 TCID50) increased the humoral immune response against CPV in all groups. Regarding CCoV, green propolis showed no adjuvant activity. Already titration of the antibodies showed an increase in animals inoculated with 1.5 and 3.0 x106 TCID50 of antigens co-administered with aqueous extract of brown propolis. The cellular response was assessed by the expression of messenger RNA (mRNA) for interferon gamma (INFı), revealing that the green propolis showed no adjuvant activity, while the brown propolis increased the production of this cytokine against CPV in animals inoculated with 0.75 and 3.0 x106 TCID50 of antigens. The production of INF-ı specific to CCoV revealed properties immunostimulating agent of green propolis in concentrations of 0.75 and 3.0 x106 TCID50 of antigens and of brown propolis at a dose of vaccine of 3.0 x106 TCID50. The results presented in this study demonstrated that the ethanol extract of green propolis increased humoral response against CPV and cellular response against CCoV.And the aqueous extract of brown propolis has adjuvant activity on the humoral and cellular immune responses against the attenuated CPV and inactivated CCoV, when incorporated into a multiple vaccine. The use of propolis may contribute to the effectiveness of multiple vaccines due its stimulating activity to both the humoral and cellular immune responses, which justifies more research in that area.
As vacinas com antígenos múltiplos têm representado um grande avanço na imunização de animais de companhia e de produção, já que aliam economias de tempo, custo, manejo e estresse. No entanto, a eficiência dessas vacinas tem sido por vezes questionada e a escolha de um adjuvante adequado pode significar um avanço nas imunizações múltiplas. Nesse contexto, a própolis, que vem chamando a atenção de muitos pesquisadores devido as suas propriedades bioativas, surge como uma possível candidata, pois muitas pesquisas vêm demonstrando suas atividades moduladoras sobre o sistema imune humoral e celular. Como estudos já demonstraram atividade adjuvante em vacinas inativadas e monovalentes, mas ainda não existem relatos sobre sua ação em vacinas múltiplas e atenuadas, o objetivo desse trabalho foi avaliar a capacidade imunomoduladora de extratos etanólico de própolis verde e aquoso de própolis marrom, contra o parvovírus canino (CPV) atenuado e o coronavírus canino (CCoV) inativado, quando associados com uma vacina composta por antígenos múltiplos. A própolis verde estimulou à produção de anticorpos contra o CPV nos animais inoculados com a maior concentração dos antígenos (3,0x106 TCID50) co-administrados com 400 μg de seu extrato etanólico. A adição de 400 μg/dose de extrato aquoso de própolis marrom a diferentes concentrações dos antígenos comerciais (0,75, 1,5 e 3,0 x 106 TCID50) incrementou a resposta imune humoral contra o CPV em todos os grupos. Com relação ao CCoV, a titulação dos anticorpos não revelou atividade adjuvante da própolis verde, no entanto foi verificado aumento na resposta humoral nos animais inoculados com 1,5 e 3,0x106 TCID50 dos antígenos co-administrados com extrato aquoso de própolis marrom. A resposta celular foi avaliada pela expressão de RNA mensageiro (mRNA) para interferon gamma (INF-ı), revelando que a própolis verde não apresentou ação imunoestimulante, já a própolis marrom incrementou a produção dessa citocina contra CPV nos animais inoculados com 0,75 e 3,0x106 TCID50 dos antígenos. A produção de INF-ı específico para CCoV revelou propriedade imunoestimulante da própolis verde nas concentrações de 0,75 e 3,0 x106 TCID50 dos antígenos e da própolis marrom na dose de vacina de 3,0x106 TCID50. Os resultados apresentados nesse estudo demonstraram que o extrato etanólico de própolis verde incrementou a resposta humoral contra o CPV e a celular contra o CCoV. Já o extrato aquoso de própolis marrom apresentou atividade adjuvante sobre as respostas imunes humoral e celular, contra o CPV atenuado e o CCoV inativado, quando incorporado a uma vacina múltipla. O uso da própolis pode contribuir para a eficácia de vacinas múltiplas devido à atividade estimulante tanto sobre a resposta imune humoral como celular, justificando mais pesquisas nessa área.

New Zealand Black/White F₁ hybrid (NZB/W) and MRL/Mp-lpr/lpr (MRL/lpr) mice spontaneously develop a Systemic Lupus Erythematosus-like autoimmune disease. While the primary immunologic defect in the NZB/W is due to B cells, in the MRL/lpr it is a result of T cell abnormalities. Diethyldithiocarbamate (DTC), an agent suggested to enhance T cell function, was used to treat both strains. Weekly treatment of NZB/W mice with 25 mg/kg DTC had no significant effect upon survival or autoantibody levels but did induce changes in cell surface antigen expression. MRL/lpr mice treated with DTC displayed normalization of cell surface antigen expression (particularly increased expression of Lyt-2, macrophage markers and Lyt-2⁺/L3T4⁺ thymocytes), decreased lymphoproliferation and thymic atrophy, decreased serum autoantibody levels and kidney deposition of C3 and IgM, restored responses to mitogens and significantly prolonged survival. To determine both the influence of MRL background and lpr genes and to better understand on what cell populations DTC effects, changes in cell surface antigen expression were examined in DTC treated MRL-+/+, Balb/c, and Balb/lpr strains. The only consistent similarities observed between all strains tested were DTC induced changes in Mac-1 splenocyte surface antigen expression. In vitro studies showed DTC to have variable effects upon the mitogenic responses of lymphoid cells to phytohemagluttinin, but DTC alone stimulated both MRL/lpr and Balb/lpr lymphocytes. DTC stimulated the null cell population that predominates in lpr gene-bearing mice, but all observed in vitro effects of DTC were dependent upon the adherent cell population included in culture. DTC had no apparent direct effects upon adherent cells alone however. These studies have shown that DTC is capable of positive effects upon one autoimmune murine strain, the MRL/lpr, but not the NZB/W. DTC appears to affect macrophages, but other cell populations are required to obtain full activity of this compound. The variable effects of DTC emphasize the need to define the immunopathology of individual patients with autoimmune disease before initiating treatment with immunomodulative therapy.

A sílica SBA-15 devido às suas propriedades físico-química e estrutural tem demonstrado efeito adjuvante, carreando, protegendo e liberando antígenos. Nesse estudo avaliou-se o seu efeito sobre a atividade fagocítica de macrófagos; no recrutamento de células para órgãos linfóides; na expressão de moléculas MHC de classe II e co-estimuladoras pelas APCs; e a influência do tempo de contato imunógeno:SBA15 no potencial de adsorção e geração de anticorpos. Experimentos in vitro evidenciam que diferentes concentrações da SBA-15 não afetam a morfologia ou atividade de macrófagos. A SBA15 induz o recrutamento de macrófagos, células dendríticas, CD4+, CD8+ e B220+ para os linfonodos drenantes, promovendo aumento de expressão de moléculas co-estimuladoras. As análises da produção de anticorpos demonstram que o contato imunógeno:sílica é importante na adsorção e melhora da resposta imune. Esses resultados sugerem que o potencial adjuvante da SBA-15 relaciona-se com a capacidade de adsorver antígenos e liberá-los às APCs, influindo diretamente na reposta imunológica.
The SBA-15 silica is a polymer that due to its physico-chemical and structural properties has shown adjuvant effect, carrying, protecting and delivering antigens. In this study was evaluated the effect of SBA15 in the phagocytic activity of macrophages; recruitment of cells to lymphoid organs; expression of MHC class II and co-stimulatory molecules by the APCs, and the influence of contact time between immunogen:SBA-15 in potential for absorption and generation of antibodies. In vitro experiments showed that different concentrations of SBA-15 do not affect the morphology or macrophage activity. SBA-15 induces the recruitment of macrophages, dendritic cells, CD4+, CD8+ and B220+ to the draining lymph nodes, increasing the expression of co-stimulatory molecules. Analyses of antibody production showed that the contact immunogen:silica is important for adsorption and improves the immune response. These results suggest that the adjuvanticity of SBA-15 is related to its ability in antigens adsorption and release to APCs, directly influencing the immune response.

Flagelinas de bactérias gram-negativas ativam o sistema imune inato resultando em efeitos adjuvantes para antígenos co-administrados. No entanto, não existem relatos sobre as propriedades adjuvantes de flagelinas de bactérias gram-positivas. O objetivo do projeto foi estudar os efeitos imunomoduladores da flagelina Hag de B. subtílis. Inicialmente foi purificada a Hag e subseqüentemente avaliada sua propriedade imunológica quando administrada junto com a ovalmbumina (OVA) pelas vias intra-nasal (i.n.) ou subcutânea (s.c.) em camundongos Balb/C e C57BL/6. Os resultados demonstraram as propriedades imunomoduladoras da Hag nas duas linhagens em relação à indução de anticorpos antígeno-específicos. Não foi possível demonstrar a ativação de linfócitos TCD4+ e CD8+ antígenos-específicos em animais Balb/C imunizados com OVA e Hag tanto pela via s.c. como pela i.n.. Resultados mais promissores do efeito adjuvante frente a células T foram encontrados em animais C57BL/6. Os resultados abrem perspectivas para o estudo do potencial da flagelina Hag de B. subtilis como adjuvante vacinal.
Flagellin of gram negatives bacteria actives the innate immune system resulting in adjuvants effects against coadministrated antigens. However, there is not information about immunological properties of flagellins produced by gram positive bacteria. This study aimed the evaluation of immunomodulator effects of Hag flagellin from B. subtilis. Vaccine formulations based in purified Hag and Ovalbumine protein (OVA) were administrated intranasal (i.n.) and subcutaneously (s.c.) in Balb/C and C57BL/6 mice and then the population of B and T lymphocytes were monitored for production of antibodies and citocines and/or surface markers expression. Results showed the immunomodulatory properties of Hag in both mice lineages regarding the induction of antigen specific antibodies when immunized with OVA and Hag by i.n. and s.c. via. Most promising results concerning the adjuvant effects observed on T cells activation were found in C57BL/6 mice. The results obtained open future perspectives for the study of the potential use of B. subtilis Hag flagellin as adjuvant in vaccines.