Résumé
Protamine sulphate/DNA complexes have been shown to protect DNA from DNase digestion in a lipid system for gene transfer. A DNA-based vaccine complexed to protamine sulphate was used to induce an immune response against Schistosoma mansoni anchored-glycosylphosphatidylinositol tegumental antigen in BALB/c mice. The protection elicited ranged from 33 to 44 percent. The spectrum of the elicited immune response induced by the vaccine formulation without protamine was characterized by a high level of IgG (IgG1> IgG2a). Protamine sulphate added to the DNA vaccine formulation retained the green fluorescent protein encoding-plasmid longer in muscle and spleen. The experiments in vivo showed that under protamine sulphate effect, the scope of protection remained unchanged, but a modulation in antibody production (IgG1= IgG2a) was observed.
Sujets)
Animaux , Femelle , Souris , Anticorps antihelminthe/immunologie , Antigènes d'helminthe/immunologie , Glycosylphosphatidylinositols/immunologie , Antagonistes de l'héparine/immunologie , Protamine/immunologie , Schistosoma mansoni/immunologie , Vaccins à ADN/immunologie , Anticorps antihelminthe/sang , Antigènes d'helminthe/administration et posologie , Glycosylphosphatidylinositols/administration et posologie , Antagonistes de l'héparine/administration et posologie , Immunoglobuline G/immunologie , Souris de lignée BALB C , Protamine/administration et posologie , Schistosomiase à Schistosoma mansoni/prévention et contrôle , Facteurs temps , Vaccins à ADN/administration et posologieRésumé
In the present report we analyzed the levels of IgG1, IgG2a, IgG2b and IgG3 isotypes from Balb/c mice immunized with cytoplasmic repetitive antigen (CRA), and flagelar repetitive antigen (FRA) of Trypanosoma cruzi. The immunization was done by subcutaneous route three times (20 days apart) and the analysis was performed 14 days after each treatment. CRA-immunized mice produced high levels of all IgG isotypes, mainly IgG3 and IgG1. FRA-immunization elicited only high levels of IgG1
Sujets)
Animaux , Souris , Isotypes des immunoglobulines , Trypanosoma cruzi , Immunisation , Souris de lignée BALB CRésumé
In the present communication we analyzed the levels of IgG1, IgG2, IgG3, IgG4 and IgE isotypes to soluble egg antigen of Schistosoma mansoni by ELISA in individuals from an endemic area for schistosomiasis in Northeast Brazil. The analysis was performed before and after treatment to evaluate the age-dependent pattern, and to identify differences in the reactivities to antigens. Our results suggest that schistosomiasis treatment would not interfere with this sort of immune response
Sujets)
Animaux , Humains , Anticorps antihelminthe , Antigènes d'helminthe , Immunoglobuline G , Schistosoma mansoni , Schistosomiase à Schistosoma mansoni , Brésil , Test ELISA , Fèces , Oxamniquine , Schistosomiase à Schistosoma mansoni , SchistosomicidesRésumé
A kit based on an enzyme immunoassay, EIE-Recombinant-Chagas-Biomanguinhos, developed by the Oswaldo Cruz Foundation, was evaluated for the serodiagnosis of chronic Chagas disease. Evaluation was performed with 368 serum samples collected from individuals living in an endemic area for Chagas disease: 131 patients in the chronic phase with confirmed clinical, epidemiological, and serological diagnosis (indirect immunofluorescence, indirect hemagglutination or enzyme-linked immunosorbent assay) and 237 nonchagasic seronegative individuals were considered negative control. The EIE-Recombinant-Chagas-Biomanguinhos kit showed high sensitivity, 100 percent (CI 95 percent: 96.4-100 percent) and high specificity, 100 percent (CI 95 percent: 98-100 percent). The data obtained were in full agreement with clinical and conventional serology data. In addition, no cross-reaction was observed with sera from patients with cutaneous (n=14) and visceral (n=3) leishmaniasis. However, when these sera were tested by conventional serological assays for Chagas disease, cross-reactions were detected in 14.3 percent and 33.3 percent of the patients with cutaneous and visceral leishmaniasis, respectively. No cross-reactions were observed when sera from nonchagasic seronegative patients bearing other infectious disease (syphilis, n=8; HTLV, n=8; HCV, n=7 and HBV, n=12) were tested. In addition, sera of patients with inconclusive results for Chagas disease by conventional serology showed results in agreement with clinical evaluation, when tested by the kit. These results are relevant and indicate that the refered kit provides a safe immunodiagnosis of Chagas disease and could be used in blood bank screening
Sujets)
Humains , Animaux , Enfant d'âge préscolaire , Enfant , Adolescent , Adulte , Adulte d'âge moyen , Antigènes de protozoaire/sang , Maladie de Chagas/diagnostic , Protéines recombinantes/immunologie , Maladie de Chagas/sang , Maladie chronique , Techniques immunoenzymatiques/méthodes , Sensibilité et spécificité , Tests sérologiques , Trypanosoma cruzi/immunologieRésumé
Os polipeptídeos de 46 e 58kDa foram reconhecidos em diferentes cepas de T. cruzi (Y, WSL e Colombiana) pelo soro de todos os pacientes chagásicos estudados. Estes polipeptídeos foram isolados da cepa Y e usados em ELISA. A sensibilidade e especificidade foram 97,6 por cento [CI 95 por cento: 86-100 por cento] e 100 por cento [CI 95 por cento: 89,3-100 por cento], respectivamente quando Tc 46 foi usada. Quando Tc 58 foi utilizada a sensibilidade e especificidade foram de 100 por cento [CI 95 por cento: 89,6-100 por cento] e 90,2 por cento [CI 95 por cento: 75,9-96,8 por cento], respectivamente