Inhibition of caspase-8 activity reduces IFN-gamma expression by T cells from Leishmania major infection

Anais da Academia Brasileira de Ciências

Wânia F. Pereira¹  Landi V.c. Guillermo¹  Flávia L. Ribeiro-gomes¹  Marcela F. Lopes¹ 

[1] ,Universidade Federal do Rio de Janeiro Centro de Ciências da Saúde Instituto de Biofísica Carlos Chagas FilhoRio de Janeiro RJ ,Brasil

关键词: apoptosis;    caspase-8;    CD8 T cells;    IFN-gamma;    Leishmaniasis;    apoptose;    caspase-8;    células T CD8;    IFN-gama;    Leishmanioses;   

DOI  :  10.1590/S0001-37652008000100008

来源: SciELO

【 摘 要 】

Following infection with Leishmania major, T cell activation and apoptosis can be detected in draining lymph nodes of C57BL/6-infected mice. We investigated the mechanisms involved in apoptosis and cytokine expression following Tcellactivation. After two weeks of infection, apoptotic T cells were not detected in draining lymph nodes but activation with anti-CD3 induced apoptosis in both CD4 and CD8 T cells. Treatment with anti-FasLigand, caspase-8 or caspase- 9 inhibitors did not block activation-induced T-cell death. We also investigated whether the blockade of caspase-8 activity would affect the expression of type-1 or type-2 cytokines. At early stages of infection, both CD4 and CD8 T cells expressed IFN-gamma upon activation. Treatment with the caspase-8 inhibitor zIETD-fmk (benzyl-oxycarbonyl-Ile- Glu(OMe)-Thr-Asp(OMe)-fluoromethyl ketone) reduced the proportion of CD8 T cells and IFN-gamma expression in both CD4 and CD8T cells. We conclude that a non apoptotic role of caspase-8 activity may be required for T cell-mediated type-1 responses during L. major infection.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License