Figure 1.

Different Mtb components stimulate the immune system through Toll-like receptors (TLRs). The role of each TLR is depicted in this figure separately. TLRs interact with Mtb components and cause the activation of macrophages, NK cells, dendritic and T cells and also induce cytokine secretion. Such roles of TLRs is crucial in primary identification of Mtb and development of appropriate immune responses to overcome the Mtb infection. LM: Lipomannan, Hsp: Heat Shock Protein, HBHA: Heparin-binding hemagglutinin, Rpf: Resuscitation-promoting factor, CAF: Cationic adjuvant formulation, MPL: Monophosphoryl lipid-A, TDM: Trehalose dimycolate, ESAT: Early secreted antigen, Nk cell: Natural killer cell, IFN-γ: Interferon-Gamma, DC: Dendritic cell, Th: T helper, MMP: Matrix metalloproteinase, MAPK: Mitogen-activated protein kinase, NF-κB: nuclear factor kappa-light-chain-enhancer of activated B cells, TNF: Tumor necrosis factor, IL: Interleukin.