Tumor-associated macrophage surface antigen

Tumor-associated macrophage (TAM) surface antigens represent a diverse class of proteins expressed on the plasma membrane of macrophages that reside within the tumor microenvironment (TME). These antigens, which include Colony-stimulating factor 1 receptor (CSF1R), CD163, CD206 (Mannose receptor), and MARCO, serve as critical markers for identifying TAM subsets and as therapeutic targets for cancer immunotherapy (NIH, 2012; Wikipedia, 2024). TAMs typically exhibit an M2-like, pro-tumoral phenotype that promotes angiogenesis, suppresses cytotoxic T-cell activity, and facilitates tumor invasion and metastasis (NIH, 2021; ResearchGate, 2023). By targeting these surface antigens with monoclonal antibodies, small molecule inhibitors, or antibody-drug conjugates, researchers aim to either deplete the TAM population or reprogram them into M1-like, anti-tumoral macrophages (NIH, 2021). Therapeutic strategies targeting these antigens, such as the CSF1R inhibitor pexidartinib, are currently being evaluated in clinical trials, often in combination with immune checkpoint inhibitors to overcome resistance and enhance anti-tumor immunity (NIH, 2021; Wikipedia, 2024).

Other names

CD163CD206Mannose receptorCSF1RColony-stimulating factor 1 receptorMARCOCD204Scavenger receptor class ATREM2Siglec-15Folate receptor betaFOLR2

Inhibition of CSF1R signaling to deplete TAMs; targeting scavenger receptors (CD163, CD204) or mannose receptors (CD206) to repolarize TAMs from a pro-tumor (M2) to an anti-tumor (M1) phenotype; blockade of immunosuppressive checkpoints on the macrophage surface.