Humberto Menezes
U.S.P. Departamento de Patologia - Faculdade de Medicina - Ribeirão Prêto, São Paulo. Brasil
ABSTRACT
Antiproliferative drugs (Azathioprine and Methotrexate) were able to enhance a T. cruzi virulent infection in mice, but failed to induce evident infection in animais previously vaccinated with the live PF strain of the same parasite.
Vinblastine (Vbl) had a similar effect with the virulent Y strain, but promoted the appearance of positive blood eultures in animais vaecinated and treated previously with the drug. Negative results are obtained if the immunosupressive agent is used 15 days after the vaccine. The flagellates isolated from the vaccinated Vbl treated mice remained avirulent for baby mice, after i. p. inoculation.
The immunity induced by the PF strain is probably sterile i. e. does not imply in the persistence of a latent infection (premunition).
RESUMO
Drogas imunossupressoras (Azathioprina e Methotrexato) que se mostraram capazes de agravar infecções experimentais por Trypanosoma cruzi virulento (cepa Y), em camundongos, não conseguiram favorecer o aparecimento de qualquer sinal de infecção em animais vacinados com a cepa avirulenta PF do mesmo tripanosoma.
Vinblastine, quando dado 3 dias antes da vacina, não favoreceu parasitemias positivas nem mortalidade significativamente aumentada, mas induziu o aparecimento de hemoculturas positivas.
Os tripanosomas dessas culturas foram incapazes de infectar camundongos jovens. Quando o Vinblastine foi usado 15 dias após a vacinação dos animais, todos os testes foram negativos, inclusive as hemoculturas.
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Submitted to publication on 10.6.1971.
