L-selectin

L-selectin is also known as LECAM-1, LAM-1, Mel-14 antigen, gp90$^{mel}$, and Leu8/TQ-1 antigen. L-selectin is the smallest of the vascular selectins and constitutively expressed at most of leucocytes [TLK93]. This adhesion molecule contributes greatly to the capture of leukocytes during the early phases of the adhesion cascade. Following capture, L-selectin is rapidly shed from the leukocyte surface, which is stimulated by LTB-4, C5a, TNF- , IL-1 and PAF[GK94]. Several studies have been used to investigate the role of L-selectin in leukocyte rolling and adhesion in post-capillary venules Vey et al,. 1991[HMTP$^+$01]. L-selectin can use both E-selectin and P-selectin on endothelial cell as ligands, presumably by interacting with sialylated carbohydrate moieties on these molecules [SKA$^+$91,KWJ$^+$91]. L-selectin mediated binding does not require activation of the leukocyte. Down-regulation of L-selectin occurs within minutes and is a result of shedding of the select-in from the leukocyte surface rather than internalization of the molecule [KR94].