Fig. 1

Mechanisms of immunosuppression of TIGIT in TME. A. CD155 binds with TIGIT with higher affinity compared to CD226 leading to deactivation of T or NK cells. In addition, CD155 is associated with drug resistance, and tumor cell migration and metastasis. Fap2, secreted from F. nucleatum, triggers inhibition by binding to TIGIT. B. The interaction of CD112 and CD112R, or TIGIT, inhibits proliferation of T-cells and NK cells by reducing IFN-γ production. CD155 increases IL-10 production by binding to TIGIT. C. TIGIT on Treg activates its immunosuppression on Th1, Th17, and effector T cells. D. The binding of TIGIT and CD155 on memory B cells exhibits deactivated DCs and inhibits Th1/17/2. E. The production of IL-10 from DCs inhibits TILs