title: L-selectin serves as an E-selectin ligand on cultured human T lymphoblasts.
abstract: Previous studies reported that L-selectin (CD62L) on human peripheral blood neutrophils serves as an E-selectin ligand. This study shows that CD62L acquired E-selectin-binding activity following phorbol ester (PMA) treatment of the Jurkat T cell line and anti-CD3/IL-2-driven proliferation of human T lymphocytes in vitro. The recombinant porcine E-selectin/human Ig chimera P11.4 showed neuraminidase-sensitive and calcium-dependent attachment to PMA-stimulated human Jurkat T cells in a flow cytometry assay. The anti-CD62L mAb (DREG 56) blocked this binding interaction by approximately 60% and P11.4 precipitated CD62L from detergent lysates of PMA-activated Jurkat cells. In contrast, P11.4 precipitated minimal amounts of CD62L from detergent lysates of nonactivated human PBL. As reported previously, P-selectin glycoprotein ligand 1 and a distinct 130-kDa glycoprotein were the major species in these precipitates. However, T cell activation on plate-immobilized anti-CD3 and growth in low-dose IL-2 increased the percentage of CD62L molecules with E-selectin-binding activity. After two cycles of activation and culture, approximately 60-70% of the CD62L was precipitated with the P11.4 chimera. These cultured T lymphoblasts rolled avidly on both E-selectin and P-selectin at physiologic levels of linear shear stress. The DREG 56 Ab partially blocked rolling on the E-selectin substrate, whereas no effect was seen on P-selectin. Thus, CD62L on human cultured T lymphoblasts is one of several glycoproteins that interacts directly with E-selectin and contributes to rolling under flow.
authors.affiliation: Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717, USA. uvsmj@montana.edu
authors.forename: Mark A
authors.initials: MA
authors.lastname: Jutila
authors.forename: Sandy
authors.initials: S
authors.lastname: Kurk
authors.forename: Larrisa
authors.initials: L
authors.lastname: Jackiw
authors.forename: Randall N
authors.initials: RN
authors.lastname: Knibbs
authors.forename: Lloyd M
authors.initials: LM
authors.lastname: Stoolman
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D002465:Cell Movement; D002478:Cells, Cultured; D019040:E-Selectin / Q000378:metabolism*; D006801:Humans; D019169:Jurkat Cells; D019041:L-Selectin / Q000378:metabolism*; D008024:Ligands; D008213:Lymphocyte Activation / Q000187:drug effects; D019007:P-Selectin / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000502:physiology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D019040:E-Selectin; D008024:Ligands; D019007:P-Selectin; D011993:Recombinant Fusion Proteins; D019041:L-Selectin; D013755:Tetradecanoylphorbol Acetate