Processing of Mycobacterium tuberculosis bacilli by human monocytes for CD4+ alphabeta and gammadelta T cells: role of particulate antigen
Abstract
Mycobacterium tuberculosis readily activates both CD4+ and Vdelta2+ gammadelta T cells. Despite similarity in function, these T-cell subsets differ in the antigens they recognize and the manners in which these antigens are presented by M. tuberculosis-infected monocytes. We investigated mechanisms of antigen processing of M. tuberculosis antigens to human CD4 and gammadelta T cells by monocytes. Initial uptake of M. tuberculosis bacilli and subsequent processing were required for efficient presentation not only to CD4 T cells but also to Vdelta2+ gammadelta T cells. For gammadelta T cells, recognition of M. tuberculosis-infected monocytes was dependent on Vdelta2+ T-cell-receptor expression. Recognition of M. tuberculosis antigens by CD4+ T cells was restricted by the class II major histocompatibility complex molecule HLA-DR. Processing of M. tuberculosis bacilli for Vdelta2+ gammadelta T cells was inhibitable by Brefeldin A, whereas processing of soluble mycobacterial antigens for gammadelta T cells was not sensitive to Brefeldin A. Processing of M. tuberculosis bacilli for CD4+ T cells was unaffected by Brefeldin A. Lysosomotropic agents such as chloroquine and ammonium chloride did not affect the processing of M. tuberculosi...Continue Reading
References
Citations
Related Concepts
Related Feeds
Antimalarial Agents
Antimalarial agents, also known as antimalarials, are designed to prevent or cure malaria. Discover the latest research on antimalarial agents here.
Antimalarial Agents (ASM)
Antimalarial agents, also known as antimalarials, are designed to prevent or cure malaria. Discover the latest research on antimalarial agents here.