Development of high numbers of blood trypomastigotes of Trypanosoma cruzi in nude rats

Abstract

The development and pathogenicity of a Trypanosoma cruzi strain ("Chile 5") of low virulence were studied after infection of nude rats with different doses of blood trypomastigotes (10-10(7) parasites/rat). Peak parasitemias were correlated with the infection dose, which also influenced the mean survival times (26-36 days post-infection). Within 26 or 27 days, a subcutaneous injection of 10(7) blood trypomastigotes developed to about 8-20 x 10(7) parasites/ml.

“Natural infections” with Trypanosoma cruzi via the skin of mice: size of mouthparts of vectors and numbers of invading parasites

“…The prepatent period especially seemed to reflect the number of parasites infecting the mice, more evident in series 3. This was more strictly evident in infections of nude rats using 10–10,000,000 blood trypomastigotes (Schaub et al 2001 ). In the present investigation, the variation of parasitemias within a group was high after receiving a low dose.…”

“…The immunodeficient Balb/c nu/nu (nude) mice originated from the Max Planck Institute of Immunobiology, Freiburg, Germany, and the immunocompetent C57 Bl/6 mice were bread at our institute. Nude mice were chosen, since nude rats showed a good dose-dependent development of parasitemias (Schaub et al 2001 ). Commercial rodent diet and water, sterilised in case of the nude mice, were available ad libitum.…”

Participação do eixo Th17/IL-27 no controle da infecção experimental com <i>Trypanosoma cruzi</i>

“…Outras células fundamentais para o controle do parasito são os linfócitos T CD4 + e T CD8 + , visto que há intensa proliferação de parasitos em animais geneticamente deficientes de linfócitos T, com subsequente morte prematura destes hospedeiros (RODRIGUEZ et al, 1983;SCHAUB et al, 2001). É perfeitamente compreensível que linfócitos desempenhem funções importantes no controle do T. cruzi, já que estas células são fontes essenciais da produção de IFN-γ, a principal citocina envolvida na ativação de macrófagos (METZ et al, 1993).…”