Allograft inflammatory factor 1-like (AIF1L)

Allograft inflammatory factor 1-like (AIF1L) is an actin-binding protein encoded by the *AIF1L* gene on human chromosome 9 (C9orf58)[4]. Unlike the closely related Allograft inflammatory factor 1 (AIF1), which is a well-studied calcium-binding protein with documented roles in macrophage activation, inflammation, and transplant rejection, AIF1L may not bind calcium and its functional importance in humans remains largely unclear[4]. It has been shown to promote actin bundling and is biased in expression toward the kidney and spleen[4]. While studies in animal models (e.g., chicken) suggest roles in immune cell viability[2], no direct evidence links AIF1L specifically to human disease processes, drug interactions, or therapeutic targeting. The literature frequently confuses AIF1L with AIF1; AIF1 is the functionally characterized protein in inflammation and immune response, while the significance of AIF1L is yet to be determined. Key distinctions: *AIF1L* ("Allograft inflammatory factor 1-like") is biologically distinct from *AIF1* ("Allograft inflammatory factor 1"), and only the latter is a recognized inflammatory disease biomarker and research target[1][3][4]. *AIF1L* has not been described as a receptor, enzyme, or therapeutic target in the medical literature[4][2]. Common misattributions include "IBA2," "Ionized calcium-binding adapter molecule 2," and much of the biology attributed to AIF1, not AIF1L[1][3][4].

Other names

C9orf58AIF1LAllograft inflammatory factor 1-like

None known