Test Details: CD103 is a type I transmembrane glycoprotein known as αE integrin. It belongs to the integrin family and is primarily found on intestinal intraepithelial lymphocytes (IEL). CD103 is also expressed on a subpopulation of lamina propria T cells, epithelial dendritic cells, lamina propria-derived dendritic cells, and a small subset of peripheral lymphocytes. It is used as a marker to diagnose hairy cell leukaemia in flow cytometry. The CD103 antibody helps recognize the integrin subunit i.e. CD103 cell surface antigen, which is expressed in HCL which is a B-cell lymphoproliferative disorder.