Allograft inflammatory factor 1 (AIF1)

Allograft inflammatory factor 1 (AIF1), also known as ionized calcium-binding adapter molecule 1 (IBA1), is a cytoplasmic, actin- and calcium-binding protein encoded by the AIF1 gene located in the major histocompatibility complex class III region in humans[1][4]. AIF1 is highly expressed in cells of the immune and vascular systems, especially in activated macrophages and microglia, and is upregulated by interferon-γ and pro-inflammatory cytokines[1][4]. It regulates immune cell activation, promotes proliferation and migration of vascular smooth muscle cells and endothelial cells, and influences T-cell cytokine release and polarization[1][2]. AIF1 plays an important role in inflammation, autoimmune responses, vascular remodeling, and is implicated in the progression of various cancers, where its expression correlates with tumor aggressiveness, immune infiltration, and prognosis[1][2]. AIF1 is also investigated as a biomarker for inflammatory states and metabolic disorders including diabetes and diabetic nephropathy, and is used as a marker of microglia/macrophage activation in research and clinical pathology[1][2][4]. Although not a classical receptor, ion channel, or enzyme, AIF1's central role in inflammation and cell signaling makes it a candidate therapeutic target in diseases characterized by immune activation and tissue remodeling.

Other names

Ionized calcium-binding adapter molecule 1IBA1AIF-1IRT-1Protein G1Interferon gamma responsive transcriptEm:AF129756.17