ANDREA DA COSTA
Projetos de Pesquisa
Unidades Organizacionais
LIM/49 - Laboratório de Protozoologia, Hospital das Clínicas, Faculdade de Medicina
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conferenceObject GAMMA IRRADIATED SOLUBLE EXTRACTS OF TOXOPLASMA GONDII TACHYZOITES INDUCED BETTER HUMORAL AND CELLULAR IMMUNE RESPONSE DUE TO PREFERENTIAL UPTAKE BY APCS SCAVENGER RECEPTORS(2017) COSTA, Andrea da; ZORGI, Nahiara E.; NASCIMENTO, Nanci do; GALISTEO JR., Andres J.; ANDRADE JR., Heitor F. de- Radiation effects on Toxoplasma antigens: different immune responses of irradiated intact tachyzoites or soluble antigens in experimental mice models(2020) COSTA, Andrea da; NASCIMENTO, Nanci do; GALISTEO JR., Andres Jimenez; PASSOS, Aline Bastos Dias dos; ANDRADE JR., Heitor Franco dePurpose: Purpose: Protein irradiation causes aggregation, chain breakage, and oxidation, enhancing its uptake by antigen-presenting cells. To evaluate if irradiated proteins participate on the protection, we studied the immune response induced in mice immunized with irradiated soluble extracts of T. gondii tachyzoites (STag) or irradiated intact T. gondii RH tachyzoites (RH0.25 kGy). Material and Methods: Soluble extracts of Toxoplasma gondii tachyzoites (STag) were irradiated at different dose by Cobalt-60 source. By polyacrylamide gel electrophoresis (SDS-Page) we evaluated the effects on primary structures of protein STags induced by irradiation. By Enzyme-linked Immunosorbent Assay (ELISA) we evaluated the difference between humoral immune response induced by irradiated STag or RH tachyzoites in immunized mice from the detection of specific immunoglobulin G (IgG) antibodies in the serum of immunized mice. From challenge with viable RH strain of T. gondii we evaluated the protection induced in the immunized animals. By cytometry we performed the phenotyping of T and B lymphocytes in the peripheral blood of the immunized animals. Results: Irradiation dose of 1.5 kGy induced minimal changes in most proteins, without affecting their antigenicity or immunogenicity. Immunization showed saturation at the dose of 10 mu g/mice, with worst response at higher doses. STag irradiated at 1.5 kGy (STag(1.5 kGy)) induced higher survival and protection similar to T. gondii RH strain irradiated at 0.25 kGy (RH0.25 kGy), with higher serum levels of high affinity IgG compared to STag native. Blood immune memory cells of mice immunized with STag(1.5 kGy) had higher proportions of CD19(+) (cluster of differentiation 19) and CD4(+) (cluster of differentiation 14) cells, whereas mice RH0.25 kGy had high proportion of memory CD8(+) (cluster of differentiation 8) cells. Conclusions: Our data suggest that major histocompatibility complex type I (MHCI) pathway, appears seem to be used by RH0.25 kGy to generate cytotoxic cells while STag1.5 kGy uses a major histocompatibility complex type II (MHCII) pathway for B-cell memory, but both induce sufficient immune response for protection in mice without any adjuvant. Irradiation of soluble protein extracts enhances their immune response, allowing similar protection against T. gondii in mice as compared to irradiated intact parasites.
- Characterization and evaluation of the enzymatic activity of tetanus toxin submitted to cobalt-60 gamma radiation(2021) SARTORI, Giselle Pacifico; COSTA, Andrea da; MACARINI, Fernanda Lucio dos Santos; MARIANO, Douglas Oscar Ceolin; PIMENTA, Daniel Carvalho; SPENCER, Patrick Jack; NALI, Luiz Henrique da Silva; JR, Andres Jimenez GalisteoBackground: Tetanus toxin blocks the release of the inhibitory neurotransmitters in the central nervous system and causes tetanus and its main form of prevention is through vaccination. The vaccine is produced by inactivation of tetanus toxin with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the post-vaccination side effects. Therefore, the aim of this study was to characterize the tetanus toxin structure after different doses of ionizing radiation of Co-60. Methods: Irradiated and native tetanus toxin was characterized by SDS PAGE in reducing and non-reducing conditions and MALD-TOF. Enzymatic activity was measured by FRET substrate. Also, antigenic properties were assessed by ELISA and Western Blot data. Results: Characterization analysis revealed gradual modification on the tetanus toxin structure according to doses increase. Also, fragmentation and possible aggregations of the protein fragments were observed in higher doses. In the analysis of peptide preservation by enzymatic digestion and mass spectrometry, there was a slight modification in the identification up to the dose of 4 kGy. At subsequent doses, peptide identification was minimal. The analysis of the enzymatic activity by fluorescence showed 35 % attenuation in the activity even at higher doses. In the antigenic evaluation, anti-tetanus toxin antibodies were detected against the irradiated toxins at the different doses, with a gradual decrease as the dose increased, but remaining at satisfactory levels. Conclusion: Ionizing radiation promoted structural changes in the tetanus toxin such as fragmentation and/or aggregation and attenuation of enzymatic activity as the dose increased, but antigenic recognition of the toxin remained at good levels indicating its possible use as an immunogen. However, studies of enzymatic activity of tetanus toxin irradiated with doses above 8 kGy should be further analyzed.
- Paratrygon aiereba irradiated anti-mucus serum reduce edematogenic activity induced in experimental model(2020) THOMAZI, Gabriela Ortega Coelho; COSTA, Andrea; RODRIGUES, Jaqueline Polizeli; ALVES, Glaucie Jussilane; PREZOTTO NETO, Jose Pedro; TURIBIO, Thompson de Oliveira; ROCHA, Andre Moreira; AIRES, Raquel da Silva; SEIBERT, Carla Simone; SPENCER, Patrick Jack; GALISTEO JUNIOR, Andres Jimenez; ANDRADE JUNIOR, Heitor Franco de; NASCIMENTO, Nanci doAccidents by freshwater stingrays are common in northern Brazil, there is no specific therapy for high morbidity and local tissue destruction. The irradiation of venoms and toxins by ionizing radiation has been used to produce appropriate immunogens for the production of antisera. We planned to study the efficacy of stinging mucus irradiation in the production of antisera, with serum neutralization assays of edematogenic activity and quantification of cytokines performed in animal models of immunization with native and irradiated mucus of Paratrygon aiereba, a large freshwater stingray. Antiserum potency and its cross-reactivity with mucus from other freshwater stingrays were detected by ELISA. Immunization models demonstrated the ability to stimulate a strong humoral response with elevated levels of serum IgG detectable by ELISA, and both native and irradiated mucus were immunogenic and capable of recognizing mucus proteins from other freshwater neotropical stingrays. Mucus P. aiereba causes cellular and humoral adaptive immune responses in cells of immunized mice producing antibodies and cytokines such as TNF-alpha, IL-6 and IL-17. Rabbit antisera immunized with mucus from P. aiereba irradiated at 2 kGy showed a significant reduction of mucus-induced edematogenic activity in mice. Our data suggest that the use of antisera against freshwater stingray mucus show the possibility of specific therapy for these accidents.
- Gamma irradiation of Toxoplasma gondii protein extract improve immune response and protection in mice models(2018) COSTA, Andrea da; ZORGI, Nahiara Esteves; NASCIMENTO, Nanci do; GALISTEO JUNIOR, Andres Jimenez; ANDRADE JUNIOR, Heitor Franco deGamma radiation induces protein changes that enhance immunogenicity for venoms, used in antivenin production. Coccidian parasites exposed to gamma radiation elicit immune response with protection in mice and man, but without studies on the effect of gamma radiation in soluble acellular extracts or isolated proteins. Toxoplasmosis is a highly prevalent coccidian disease with only one vaccine for veterinary use but with remaining tissue cysts. Total parasite extracts or recombinant proteins used as immunogen induce usually low protection. Here, we study gamma radiation effect on T. gondii extracts proteins (STAG) and its induced immunity in experimental mice models. By SDS-PAGE, protein degradation is seen at high radiation doses, but at ideal dose (1500 Gy), there are preservation of the antigenicity and immunogenicity, detected by specific antibody recognition or production after mice immunization. Immunization with STAG irradiated at 1500 Gy induced significant protection in mice immunized and challenged with distinct T. gondii strains. In their blood, higher levels of specific CD19(+), CD3(+)CD4(+) and CD3(+)CD8(+) activated cells were found when compared to mice immunized with STAG. Irradiated T. gondii tachyzoites extracts induce immune response and protection in mice in addition, could be a feasible alternative for Toxoplasma vaccine.