TIGIT

TIGIT (T cell immunoreceptor with Ig and ITIM domains) is a protein that in humans is encoded by the TIGIT gene. TIGIT is a member of the immunoglobulin superfamily and is expressed on certain T cells and Natural Killer (NK) cells. It is involved in the immune response and plays a role in the regulation of T cell and NK cell function. TIGIT can act as an inhibitory receptor, which contributes to the immune system's ability to avoid attacking the body's own cells and to control the immune response to external pathogens.

Function

TIGIT is found on the surface of some T cells and NK cells. It binds to specific ligands, such as CD155 (PVR) and CD112 (PVRL2), which are expressed on antigen-presenting cells and some other cell types. The interaction of TIGIT with its ligands inhibits the activation of T cells and NK cells, leading to a reduction in the immune response. This mechanism is important for maintaining immune tolerance and preventing autoimmune diseases. Additionally, TIGIT plays a role in the suppression of antitumor immunity, and its expression is often upregulated in cancer, making it a target for cancer immunotherapy.

Clinical Significance

The role of TIGIT in suppressing the immune response has made it a target for cancer immunotherapy. Inhibitors of TIGIT are being developed to block its interaction with ligands, thereby enhancing the immune system's ability to fight cancer. These therapies are in various stages of clinical trials and hold promise for improving the outcomes of patients with various types of cancer.

Research

Research on TIGIT is focused on understanding its role in immune regulation and its potential as a therapeutic target in cancer and autoimmune diseases. Studies are exploring how blocking TIGIT can enhance the immune response against tumors and investigating the potential side effects of such treatments. Additionally, research is being conducted to understand the interplay between TIGIT and other immune checkpoints in the regulation of the immune system.