title: Phenotypic and functional characterization of lymphocytes that bind human microvascular endothelial cells in vitro. Evidence for preferential binding of natural killer cells.
abstract: The microvascular endothelium has been postulated to be a critical target in the rejection of vascularized allografts. This study was undertaken to examine the ability of human sheep erythrocyte rosette forming lymphocytes (E-RFC) to form stable conjugates with microvascular endothelial cells (EC), and to assess whether a receptor-ligand interaction mediates this event. Human foreskin microvascular EC monolayers were used as targets of chromium-51-labeled E-RFC in a quantitative adherence assay. Binding was saturable, displaceable by unlabeled E-RFC, augmented by recombinant interleukin 1 (rIL-1) and inhibited by anti-LFA1 antibody. The Leu-11+ lymphocyte subset, known to be enriched for natural killer (NK) cells, bound preferentially. Only the EC-adherent lymphocyte fraction contained NK effectors, which lysed EC and classical NK targets. Thus, NK cells adhere to microvascular EC via a specific receptor-ligand interaction. The possibility exists that such binding occurs in recipients of vascularized allografts, representing the initial stage of graft rejection.
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology / Q000502:physiology; D002196:Capillaries / Q000166:cytology; D002448:Cell Adhesion; D003602:Cytotoxicity, Immunologic; D004727:Endothelium / Q000166:cytology*; D006084:Graft Rejection; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000166:cytology*; D008214:Lymphocytes / Q000145:classification* / Q000378:metabolism; D008297:Male; D008833:Microcirculation; D010641:Phenotype; D011994:Recombinant Proteins / Q000494:pharmacology; D012397:Rosette Formation
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D007375:Interleukin-1; D011994:Recombinant Proteins