Humoral and cellular immune response generated by different vaccine programs before and after Salmonella Enteritidis challenge in chickens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Humoral immune response of broilers fed diets containing yeast extract and prebiotics in the prestarter phase and raised at different temperatures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Behavior of Leishmania major metacyclic promastigotes during the course of infection and immune response development in resistant versus susceptible hosts

Pouco se conhece sobre os epítopos derivados de promastigotas metacíclicos de Leishmania que são importantes para a regulação ou destruição do parasita, como alvos de ação imunológica no hospedeiro vertebrado. Neste estudo, nós investigamos um método alternativo para obter promastigotas metacíclicos de Leishmania major, pela avaliação do curso da infecção e reação de hipersensibilidade do tipo retardado (HTR) em hospedeiros resistentes e susceptíveis. Promastigotas não-infectantes (procíclicos) de L. major, recentemente isolados de amastigotas, foram selecionados pela adesão a colunas de lã de vidro negativamente carregadas, enquanto que promastigotas metacíclicos não se aderem à coluna e podem ser recuperados com facilidade. Condições ótimas de cromatografia foram validadas por análise estatística. O rendimento médio de parasitas obtidos após separação em colunas de lã de vidro e a viabilidade dos promastigotas foram estimados por microscopia óptica. Os promastigotas metacíclicos tiveram um rendimento médio de 43,5% a 57,5%. Camundongos BALB/c (susceptíveis) e camundongos C57BL/6 (resistentes) apresentaram padrões distintos de lesões cutâneas, os primeiros com lesões mais agressivas, induzidas por promastigotas metacíclicos. As respostas à reação de HTR foram maiores nos grupos de camundongos C57BL/6, submetidos à infecção com promastigotas metacíclicos. Estes resultados indicam que o novo método poderia ser integrado aos protocolos existentes para estudar a metaciclogênese de parasitas do gênero Leishmania in vivo.

Role of Yersinia pseudotuberculosis outer proteins (Yops) in murine humoral immune response

The infection of mice with the wild-type (WT) strain of Y. pseudotuberculosis did not induce polyclonal activation of B lymphocytes. Suppression in the production of certain isotypes of Ig was observed, provoked mainly by YopH, YopJ and YpkA. The WT strain induced a progressive increase in the serum-specific IgG, which peaked after 4 weeks after infection, IgM being produced only after 1 week. Autoantibodies against phosphorylcholine, myelin, thyroglobulin and cardiolipin could be detected in the serum of mice infected with the WT strain. The infection of mice provoked suppression in the production of immunoglobulins by splenic B cells and that YopH, YopJ and YpkA must be involved here.

Vaccine immune response and interference of colostral antibodies in calves vaccinated against rabies at 2, 4 and 6 months of age born from antirabies revaccinated females

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efficiency of Matricaria chamomilla CH12 and number of doses of rabies vaccine on the humoral immune response in cattle

This study evaluated the effect of Matricaria chamomilla and vaccination frequency on cattle immunization against rabies. Four groups (n = 15/group) were treated with or without Matricaria chamomilla CH12 and vaccinated with one or two doses of rabies vaccine (30 day interval). No effect of chamomile was found on cattle immunization against rabies; however, antibody titers were protective in cattle vaccinated twice, while 93.3% of cattle vaccinated only once had titers under 0.5 UI/ml after 60 days. In conclusion, the use of chamomile did not alter the Immoral immune response in cattle, and two vaccine doses are suggested for achieving protective antibody titers.

Influence of TLR-2 in the immune response in the infection induced by fungus Sporothrix schenckii

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Immune response and performance of growing Santa Ines lambs to artificial Trichostrongylus colubriformis infections

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Immunization with pVAXhsp65 Decreases Inflammation and Modulates Immune Response in Experimental Encephalomyelitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The use of biodiversity as source of new chemical entities against defined molecular targets for treatment of malaria, tuberculosis, and T-cell mediated diseases: a review

The modern approach to the development of new chemical entities against complex diseases, especially the neglected endemic diseases such as tuberculosis and malaria, is based on the use of defined molecular targets. Among the advantages, this approach allows (i) the search and identification of lead compounds with defined molecular mechanisms against a defined target (e.g. enzymes from defined pathways), (ii) the analysis of a great number of compounds with a favorable cost/benefit ratio, (iii) the development even in the initial stages of compounds with selective toxicity (the fundamental principle of chemotherapy), (iv) the evaluation of plant extracts as well as of pure substances. The current use of such technology, unfortunately, is concentrated in developed countries, especially in the big pharma. This fact contributes in a significant way to hamper the development of innovative new compounds to treat neglected diseases. The large biodiversity within the territory of Brazil puts the country in a strategic position to develop the rational and sustained exploration of new metabolites of therapeutic value. The extension of the country covers a wide range of climates, soil types, and altitudes, providing a unique set of selective pressures for the adaptation of plant life in these scenarios. Chemical diversity is also driven by these forces, in an attempt to best fit the plant communities to the particular abiotic stresses, fauna, and microbes that co-exist with them. Certain areas of vegetation (Amazonian Forest, Atlantic Forest, Araucaria Forest, Cerrado-Brazilian Savanna, and Caatinga) are rich in species and types of environments to be used to search for natural compounds active against tuberculosis, malaria, and chronic-degenerative diseases. The present review describes some strategies to search for natural compounds, whose choice can be based on ethnobotanical and chemotaxonomical studies, and screen for their ability to bind to immobilized drug targets and to inhibit their activities. Molecular cloning, gene knockout, protein expression and purification, N-terminal sequencing, and mass spectrometry are the methods of choice to provide homogeneous drug targets for immobilization by optimized chemical reactions. Plant extract preparations, fractionation of promising plant extracts, propagation protocols and definition of in planta studies to maximize product yield of plant species producing active compounds have to be performed to provide a continuing supply of bioactive materials. Chemical characterization of natural compounds, determination of mode of action by kinetics and other spectroscopic methods (MS, X-ray, NMR), as well as in vitro and in vivo biological assays, chemical derivatization, and structure-activity relationships have to be carried out to provide a thorough knowledge on which to base the search for natural compounds or their derivatives with biological activity.

Immunodominant Antigens of Leishmania chagasi Associated with Protection against Human Visceral Leishmaniasis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relation of pretreatment sequence diversity in NS5A region of HCV genotype 1 with immune response between pegylated-INF/ribavirin therapy outcomes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Evaluation of the Naturally Acquired Antibody Immune Response to the Pv200L N-terminal Fragment of Plasmodium vivax Merozoite Surface Protein-1 in Four Areas of the Amazon Region of Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Demonstration of antibody and cellular immune response to brain extract in West and Lennox-Gastaut syndromes

Investigamos a resposta imunológica celular e humoral frente a extrato salino de tecido cerebral em 9 pacientes com síndrome de Lennox-Gastaut, 15 pacientes com síndrome de West e 20 crianças normais. A técnica de imunodifusão dupla em gel de agar (Ouchterlony) evidenciou em todos os pacientes, altos níveis de um anticorpo precipitante contra o extrato salino de tecido cerebral. O teste de inibição de migração de leucócitos com o mesmo antígeno mostrou-se positivo na maioria dos pacientes. O possível papel destas respostas autoimmunes na patogenia das sindromes de West e Lennox-Gastaut é discutido.