title: Thy-1 induced on rat endothelium regulates vascular permeability at sites of inflammation.
abstract: We investigated the role of surface adhesion molecules on endothelial cells in regulating vascular permeability, in vitro and in vivo. Cultured rat endothelial cells (REC) express Thy-1, intercellular adhesion molecule-1 (ICAM-1), CD44 and RT1A. Permeability of albumin across the REC monolayer increased through the interaction of Thy-1 and anti-Thy-1 mAb, but not through ICAM-1 and anti-ICAM-1, CD44 and anti-CD44, and RT1A and anti-RT1A mAb. This anti-Thy-1-effect was completely inhibited when the calmodulin antagonist W-7 and the protein kinase inhibitor H-7 was combined, while the IL-6-mediated increase in REC permeability was blocked by either W-7 or H-7, independently. The anti-Thy-1-mediated permeability increase was additively augmented when IL-6 was admixed. These data suggest that intracellular signaling pathways of anti-Thy-1- and IL-6-mediated permeability regulation may be overlapping to some extent but are largely independent. As anti-Thy-1-treatment generated rearrangement of vimentin filaments within REC, alteration of the cytoskeleton distribution may possibly correlate with the regulation of permeability. Although Thy-1-expression on rat vascular endothelium in vivo was not evident, it was induced at sites of Freund's complete adjuvant-induced dermatitis. The administered anti-Thy-1 mAb exclusively located on vascular endothelial surface at the sites of inflammation. Vascular permeability in inflamed skin tissues was significantly augmented when anti-Thy-1 but not anti-ICAM-1, anti-CD44 or anti-RT1A mAb was administered i.v., without affecting populations of inflammatory cells. The collective evidence suggests that Thy-1 induced on rat endothelium is one important regulatory event in vascular permeability at sites of inflammation.
authors: Department of Pathology, Hokkaido University School of Medicine, Sapporo, Japan.
authors: A
authors: A
authors: Ishizu
authors: H
authors: H
authors: Ishikura
authors: Y
authors: Y
authors: Nakamaru
authors: E
authors: E
authors: Takeuchi
authors: C
authors: C
authors: Kimura
authors: T
authors: T
authors: Koike
authors: T
authors: T
authors: Yoshiki
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002199:Capillary Permeability / Q000276:immunology* / Q000502:physiology; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*; D006649:Histocompatibility Antigens / Q000502:physiology; D018960:Hyaluronan Receptors / Q000502:physiology; D066298:In Vitro Techniques; D007249:Inflammation / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D018799:Intercellular Adhesion Molecule-1 / Q000502:physiology; D008297:Male; D051379:Mice; D051381:Rats; D011919:Rats, Inbred Strains; D018800:Thy-1 Antigens / Q000096:biosynthesis / Q000502:physiology*
chemical_list: D000911:Antibodies, Monoclonal; D006649:Histocompatibility Antigens; D018960:Hyaluronan Receptors; D018800:Thy-1 Antigens; C038353:histocompatibility antigens RT, rat; D018799:Intercellular Adhesion Molecule-1