The differentiation antigen cluster molecule 11b (CD11b) / integrin αm (ITGAM) is a transmembrane protein that forms a heterodimer composed of α and β subunits. CD11b is expressed in myeloid cells and is commonly used as a marker for myeloid cells, such as neutrophils, monocytes, macrophages, and microglia. CD11b is phosphorylated at the Ser1126 site (cytoplasmic tail region) in neutrophils. Studies have shown that this phosphorylation activity plays a role in the process of white blood cells transferring from the bloodstream to tissues. Additionally, genome-wide association studies have indicated that CD11b is associated with autoimmune diseases such as systemic lupus erythematosus (SLE).
