Figure 1

From: Toll-like receptor 9 (TLR9) agonists in the treatment of cancer

Figure 1

(1) Toll-like receptor 9 (TLR9) agonists stimulate innate and adaptive antitumor immune responses. TLR9 agonists induce secretion of interferon-α(IFN-α) from immature plasmacytoid dendritic cells (pDCs), which may activate natural killer (NK) cell lysis of tumor cells and release tumor antigens (Ags). (2) Dendritic cells activated directly or indirectly by the TLR9 agonist therapy can capture and process tumor-associated antigens, increase surface expression of major histocompatibility complex (MHC) and co-stimulatory receptors, and (3) migrate to the lymph nodes where antigens can be presented to lymphocytes, inducing (4) expansion of lymphocytes that recognize the tumor antigen. Because the response occurs in a TH1-like cytokine milieu, the lymphocyte response tends to be TH1-like, including cytotoxic T lymphocytes (CTLs).