Immune-targeting antigen

The term immune-targeting antigen refers to a broad category of molecules, typically proteins, glycoproteins, or glycans, that are expressed on the surface of diseased cells and serve as the primary recognition sites for the immune system or engineered therapeutic agents. In oncology, these antigens are classified as tumor-associated antigens (TAAs), which are overexpressed on cancer cells, or tumor-specific antigens (TSAs), such as neoantigens, which are uniquely present on malignant cells due to somatic mutations. In the context of infectious diseases, immune-targeting antigens include viral or bacterial surface proteins that are targeted by vaccines or monoclonal antibodies to neutralize pathogens. The biological function of these antigens is to facilitate immune surveillance by providing epitopes that can be presented on Major Histocompatibility Complex (MHC) molecules for T-cell recognition or directly bound by B-cell receptors and antibodies. Therapeutic strategies leveraging these antigens include chimeric antigen receptor (CAR) T-cell therapies, bispecific T-cell engagers (BiTEs), and therapeutic vaccines, all of which aim to direct a potent immune response against cells expressing the target. A significant challenge in clinical application is antigen escape, where selective pressure leads to the emergence of cell populations that lack the target antigen, as well as potential on-target off-tumor toxicities if the antigen is also present on healthy tissues.

Other names

Tumor-associated antigenTumor-specific antigenImmunotherapy target antigenNeoantigenCancer-testis antigenGlioblastoma-associated antigen

Antigen recognition by T-cell receptors or antibodies, leading to T-cell activation, antibody-dependent cellular cytotoxicity (ADCC), or complement-dependent cytotoxicity (CDC).