Interaction of leukocytes in flow with adherent leukocytes may contribute to their accumulation at sites of inflammation. Using L-selectin immobilized in a flow chamber, a model system that mimics presentation of L-selectin by adherent leukocytes, we characterize ligands for L-selectin on leukocytes and show that they mediate tethering and rolling in shear flow. We demonstrate the presence of L-selectin ligands on granulocytes, monocytes, and myeloid and lymphoid cell lines, and not on peripheral blood T lymphocytes. These ligands are calcium dependent, sensitive to protease and neuraminidase, and structurally distinct from previously described ligands for L-selectin on high endothelial venules (HEV). Differential sensitivity to O-sialo-glycoprotease provides evidence for ligand activity on both mucin-like and nonmucin-like structures. Transfection with fucosyltransferase induces expression of functional L-selectin ligands on both a lymphoid cell line and a nonhematopoietic cell line. L-selectin presented on adherent cells is also capable of supporting tethering and rolling interactions in physiologic shear flow. L-selectin ligands on leukocytes may be important in promoting leukocyte-leukocyte and subsequent leukocyte endothelial interactions in vivo, thereby enhancing leukocyte localization at sites of inflammation.
Sialylated, fucosylated ligands for L-selectin expressed on leukocytes mediate tethering and rolling adhesions in physiologic flow conditions.
R C Fuhlbrigge, R Alon, K D Puri, J B Lowe, T A Springer; Sialylated, fucosylated ligands for L-selectin expressed on leukocytes mediate tethering and rolling adhesions in physiologic flow conditions.. J Cell Biol 1 November 1996; 135 (3): 837–848. doi: https://doi.org/10.1083/jcb.135.3.837
Download citation file: