title: IL-6 acts on endothelial cells to preferentially increase their adherence for lymphocytes.
abstract: Using a quantitative monolayer adhesion assay, the current report shows that treatment of human umbilical vein endothelial cells (HUVEC) with IL-6 increases their adhesiveness for blood lymphocytes, particularly CD4+ cells, but not for polymorphonuclear cells and monocytes. This effect, which was most pronounced when using low concentrations of the cytokine (0.1-1.0 U/ml) and a short incubation period (4h), was also apparent with microvascular endothelial cells and a hybrid endothelial cell line. Skin lesions from patients with mycosis fungoides contain high levels of IL-6, and blood lymphocytes from patients with this disorder also exhibited an enhanced adhesion to IL-6-treated HUVEC. The cytokine enhanced intercellular adhesion molecule-1 (ICAM-1) expression and induced the expression of vascular cell adhesion molecule-1 (VCAM-1) and E-selectin on endothelial cells. Antibody blocking studies demonstrated that the vascular adhesion molecules ICAM-1, VCAM-1 and E-selectin and the leucocyte integrin LFA-1 all contributed to lymphocyte binding to endothelium activated by IL-6. It is proposed that IL-6 may be involved in the recruitment of lymphocytes into non-lymphoid tissue.
authors.affiliation: Department of Immunology, UMDS, St Thomas' Hospital Campus, London, UK.
authors.forename: C
authors.initials: C
authors.lastname: Watson
authors.forename: S
authors.initials: S
authors.lastname: Whittaker
authors.forename: N
authors.initials: N
authors.lastname: Smith
authors.forename: A J
authors.initials: AJ
authors.lastname: Vora
authors.forename: D C
authors.initials: DC
authors.lastname: Dumonde
authors.forename: K A
authors.initials: KA
authors.lastname: Brown
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000328:Adult; D002448:Cell Adhesion / Q000187:drug effects / Q000276:immunology; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology*; D008875:Middle Aged; D013601:T-Lymphocytes / Q000187:drug effects* / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014471:Umbilical Veins
chemical_list: D000276:Adjuvants, Immunologic; D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma