Abstract
Background & Aims : Human Toll-like receptor 1 (TLR1) is a receptor which mediated immune response to microbial lipoproteins, associates with TLR2 and recognizes the native mycobacterial lipoprotein along with TLR2. Methods : We examined the regulation of TLR1 surface expression in human peripheral blood monocytes and B cells by interferon-γ (IFN-γ) and interleukin-4 (IL-4). Results : IFN-γ up-regulated TLR1 surface expression on human peripheral blood monocytes and B cells. By contrast, IL-4 down-regulated TLR1 surface expression on human peripheral blood monocytes, but up-regulated TLR1 surface expression on human peripheral B cells. Conclusions : These results indicate that Th 1 cytokine IFN-γ enhances receptors involved in the response to native mycobacterial lipoprotein and that activation of cellular immunity may enhance defense against mycobacterium through both monocytes and B cells, whereas Th2 cytokine IL-4 modulates the receptor response to native mycobacterial lipoprotein and that activation of humoral immunity may enhance defense against mycobacterium through B cells, but not monocytes.
