title: Adhesion molecules utilized in binding of intraepithelial lymphocytes to human enterocytes.
abstract: The expression of adhesion molecules by human duodenal intraepithelial lymphocytes (IEL) was examined by two-color flow cytometry. Resting IEL expressed LFA-1, HML-1, CD44. Stimulation with phytohemagglutinin (PHA) resulted in down-regulation of expression of these molecules with induction of expression of ICAM-1 and VLA-4. VLA-4 expression was also found on non-activated IEL from patients with celiac disease. In addition, IEL expressed an antigen recognized by a novel monoclonal antibody D2.1. The molecular mass of D2.1 is heterogeneous: 82 kDa in peripheral blood lymphocytes and 44 kDa in an IEL line. Expression of this antigen was also up-regulated by PHA. To determine the involvement of these antigens in binding of IEL to human enterocytes, we developed a system based on adherence of an IEL cell line to the I407 fetal intestinal cell line. Monoclonal antibodies VLA-4, D2.1 and to a lesser extent ICAM-1 blocked adherence of IEL to I407 cells. These data suggest that VLA-4 and D2.1 may be involved in adherence of IEL to human enterocytes or secreted matrix molecules in vivo.
authors.affiliation: Department of Clinical Medicine, Trinity College, Dublin, Ireland.
authors.forename: D
authors.initials: D
authors.lastname: Kelleher
authors.forename: A
authors.initials: A
authors.lastname: Murphy
authors.forename: S
authors.initials: S
authors.lastname: Lynch
authors.forename: C
authors.initials: C
authors.lastname: O'Farrelly
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000502:physiology*; D002460:Cell Line; D006801:Humans; D018799:Intercellular Adhesion Molecule-1; D007422:Intestines / Q000166:cytology* / Q000276:immunology*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000502:physiology; D008214:Lymphocytes / Q000502:physiology*; D016029:Receptors, Very Late Antigen / Q000502:physiology
chemical_list: D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules; D016169:Lymphocyte Function-Associated Antigen-1; D016029:Receptors, Very Late Antigen; D018799:Intercellular Adhesion Molecule-1