Intratumoral regulatory T cell–associated antigen 1 (IRTA1)

Intratumoral regulatory T cell–associated antigen 1 (IRTA1), often identified as Layilin (LAYN), is a specialized cell surface receptor highly expressed on regulatory T cells (Tregs) specifically within the tumor microenvironment. Unlike systemic Tregs, those expressing IRTA1 exhibit a highly activated and suppressive phenotype, contributing significantly to tumor immune evasion by inhibiting cytotoxic T cell responses. The protein functions as a C-type lectin-like receptor and an adhesion molecule, interacting with the cytoskeleton and integrins like LFA-1 to facilitate Treg anchoring and stability within the tumor. In oncology, IRTA1 is a high-priority therapeutic target because its selective expression allows for the potential depletion of tumor-promoting Tregs while sparing systemic immune homeostasis. Experimental strategies targeting this antigen, including monoclonal antibodies and small molecule inhibitors of its associated pathways, have shown promise in reversing T cell exhaustion and sensitizing tumors to checkpoint blockade therapies.

Other names

LayilinLAYNTreg-associated antigen 1Intratumoral Treg marker 1

Selective depletion of intratumoral regulatory T cells or inhibition of their recruitment to the tumor microenvironment to restore anti-tumor CD8+ T cell activity.