Macrophage receptor with collagenous structure (MARCO)

Macrophage receptor with collagenous structure (MARCO) is a transmembrane class A scavenger receptor encoded by the MARCO gene, primarily expressed on specific macrophage subsets, dendritic cells, and B cells. It acts as a pattern recognition receptor, binding and mediating the phagocytosis of Gram-positive and Gram-negative bacteria, environmental particles, modified low-density lipoproteins (LDL), and other polyanionic ligands. MARCO plays an essential role in the innate immune system, facilitating pathogen clearance and triggering subsequent inflammatory responses through its scavenger receptor cysteine-rich (SRCR) domain. It is upregulated in response to infection and is dynamically expressed in tissues such as lymph nodes, spleen, and the liver. MARCO is implicated in the establishment of tumor-associated immunosuppression (notably by TAMs and MDSCs), and its blockade is being explored as a novel immune checkpoint target in cancer immunotherapy. Dysregulation or altered expression of MARCO is also relevant in chronic inflammatory diseases and some neurodegenerative conditions. If you need MARCO mapped to standardized identifiers or cross-references (UniProt, NCBI, etc.), this information is available upon request.

Other names

SR-A6SCARA2Scavenger receptor class A member 2MARCO protein

Antibody blockade or inhibition of MARCO can reverse macrophage-mediated immunosuppression in tumors and enhance anti-tumor immune responses. Targeting MARCO may modulate dendritic cell activation and innate-adaptive immune linkage.