Synonyms:
LEU-9; CD7; CD7 antigen (p41); CD7 molecule; CD7_HUMAN; T-cell antigen CD7; T-cell leukemia antigen; T-cell surface antigen Leu-9; CD 7; CD7 antigen; CD7 antigen p41; CD7 molecule; GP 40; GP40; LEU 9; LEU9; p41; p41 protein; T cell antigen CD7; T cell antigen CD7 precursor; T cell leukemia antigen; Tp 40; TP 41; Tp40; TP41.
Introduction:
CD7 (gp40, Leu9) is a 40 kDa member of the immunoglobulin gene superfamily. CD7 contains N-terminal amino acids 1-107 are highly homologous to Ig kappa-L chains whereas the carboxy-terminal region ofthe extracellular domain is proline-rich and has been postulated to form a stalk from which the Ig domain projects. CD7 is expressed on the majority of immature and mature T-lymphocytes, and T cell leukemia. Further, CD7 is also found on natural killer cells, a small subpopulation of normal B cells and on malignant B cells. Cross-linking surface CD7 positively modulates T cell and NK cell activityas measured by calcium fluxes, expression of adhesion molecules, cytokine secretion and proliferation. CD7 associates directly with phosphoinositol 3'-kinase. CD7 ligation induces production of D-3 phosphoinositides and tyrosine phosphorylation. Expression of CD7 is an important marker used in leukemia diagnostics.