Crotalus durissus collilineatus Venom Induces TNF- α and IL-10 Production in Human Peripheral Blood Mononuclear Cells.

Snake venom has been the subject of numerous studies in an attempt to find properties and biological effects that may be beneficial to man. In this study we evaluated in vitro the effects of Crotalus durissus terrificus (Cdt) and Crotalus durissus collilineatus (Cdc) venom in human peripheral blood mononuclear cells (PBMCs). At 24 h, a significant decrease of viable cells was observed in cells stimulated with the Cdc venom at 0.0005 mg/mL and 0.005 mg/mL compared to the negative control. At 48 h, a significant decrease of viable cells was observed only in cells stimulated with Cdc venom at 0.005 mg/mL. A significant increase of TNF- α and IL-10 was detected 48 hours after culture of PBMC with Cdc, but not with Cdt venom. The expression of CD69 and PD1 (programmed death-1), activation and regulatory cell markers, on CD8+ and CD8- T cells did not change in the presence of Cdt and Cdc venom. Our results suggest the presence of proinflammatory and anti-inflammatory components in the Cdc venom. Further analysis should be done to identify those Cdc venom components as it has been done for the Cdt venom by other authors, indicating that modulatory components are found in the venom of different species of Crotalus snakes.

Lagochilascaris minor susceptibility and Resistance to experimental Infection in mice is independent of H-2a haplotype and correlates with the immune response in immunized animals

Recently, we demonstrated that C57BL/6 mice are more susceptible to experimental lagochilascariosis than BALB/c mice. To investigate the pattern of infection and the role of the genetic background on susceptibility to infection, we studied experimental lagochilascariosis in H-2a identical B10.A and A/J mice. Infected B10.A mice had a lower survival ratio and more severe lesions in the lungs than did A/J mice. Splenocytes of A/J mice immunized with the crude extract of the parasite showed increased proliferation and produced a higher level of interleukin 10 and interferon-ã in the presence of CE or concanavalin A when compared to B10.A mice. This suggests that resistance of A/J mice may be due to less severe lesions in lungs and other organs and a better immune response to parasite antigens. This paper provides evidence that major histocompatibility complex haplotype does not influence the survival to experimental infection with L. minor.

Quadro histopatológico em camundongos isogênicos C3H/HeJ e C57BL/10 na fase aguda da infecçäo com cepas de Trypanosoma cruzi isoladas nas Regiöes Central (Goiás) e Sul (Rio Grande do Sul) do Brasil / Histopahological study in isogenic C3H/HeJ and C57BL/10 mice during the acute phase of the infection with Trypanosoma cruzi isolates from central (Goiás) and south (R.G. Sul) regions of Brazil

Foram estudadas as lesöes histopatológicas determinadas em camundongos isogênicos das linhagens C3H/HeJ(C3H) e C57BL/10(B10) por quatro cepas de Trypanosoma cruzi isoladas de triatomíneos naturalmente infectados procedentes das localidades de Mambaí, Cabeceiras, Niquelândia e Taguatinga (GO) e comparadas com as de uma cepa isolada do Rio Grande do Sul. As diferentes amostras foram submetidas previamente à caracterizaçäo morfobiológica e isoenzimática, obtendo-see para as cepas de Goiás as características biológicas do Tipo II e o zimodema 2. O estudo histopatológico evidenciou para as quatro cepas de Goiás características idênticas quanto ao tropismo tissular, determinando lesöes discretas, predominantemente no miocárdio. As duas linhagens de camundongos reagiram de maneira idêntica à infecçäo por estas cepas, com discreta predominância de lesöes na linhagem C3H. A cepa do Rio Grande do Sul apresentou um comportamento nitidamente diferente, induzindo lesöes predominantemente em músculo esquelético, característica de cepas de Tipo III, zimodema 1. Os presentes achados confirmam estudos anteriores que demonstram a predominância de cepas do Tipo II na regiäo Central do Brasil, o que pode estar correlacionado com as manifestaçöes da doença de Chagas nesta área