function:Plays a role as inhibitor of T-cells proliferation induced by CD3. Inhibits expression of IL2RA on activated T-cells and secretion of IL2. Inhibits tyrosine kinases that are required for IL2 production and cellular proliferation. Inhibits phospholipase C-gamma-1/PLCG1 phosphorylation and subsequent CD3-induced changes in intracellular free calcium. Prevents nuclear translocation of nuclear factor of activated T-cell to the nucleus. Plays a role in the inhibition of T-cell proliferation via IL10 secretion by cutaneous dendritic cells. May be a marker of CD4(+) CD56(+) leukemic tumor cells.,PTM:N-glycosylated.,similarity:Contains 7 Ig-like C2-type (immunoglobulin-like) domains.,tissue specificity:Expressed in lung, thymus and small intestine. Detected in cutaneous dendritic cells, activated T-cells, monocytes and granulocytes as well as with epithelial cells with dendritic morphology. Expressed in some leukemic cells, the CD4(+) CD56(+) blastic tumor cells, as well as in Langerhans cells from LCH (Langerhans cell histiocytosis) patients.,