SIRPCD47

SIRPCD47, also known as CD47 or Integrin-associated protein 1 (IAP1), is a transmembrane protein that plays a significant role in cellular adhesion and immune system regulation. It is ubiquitously expressed on the surface of various cell types, including red blood cells, platelets, and leukocytes. SIRPCD47 acts as a receptor for SIRPalpha (Signal Regulatory Protein alpha), a tyrosine-kinase containing receptor expressed on myeloid cells. This interaction, SIRPCD47-SIRPalpha, is a crucial "don't eat me" signal that inhibits phagocytosis by macrophages, thereby preventing the destruction of healthy cells.

Beyond its role in immune evasion, SIRPCD47 is involved in cell-cell adhesion and intracellular signaling pathways. It has been implicated in processes such as cell migration, proliferation, and differentiation. In the context of cancer, some tumor cells exploit the SIRPCD47-SIRPalpha pathway to evade immune surveillance and phagocytosis by immune cells. This makes SIRPCD47 a target of interest for cancer immunotherapy, with research exploring ways to block this interaction to enhance anti-tumor immune responses. Aberrant expression of SIRPCD47 has also been observed in certain hematological malignancies and solid tumors, suggesting its potential as a diagnostic or prognostic biomarker.