title: Nepmucin/CLM-9, an Ig domain-containing sialomucin in vascular endothelial cells, promotes lymphocyte transendothelial migration in vitro.
abstract: Nepmucin/CLM-9 is an Ig domain-containing sialomucin expressed in vascular endothelial cells. Here we show that, like CD31, nepmucin was localized to interendothelial contacts and to vesicle-like structures along the cell border and underwent intracellular recycling. Functional analyses showed that nepmucin mediated homotypic and heterotypic cell adhesion via its Ig domain. Nepmucin-expressing endothelial cells showed enhanced lymphocyte transendothelial migration (TEM), which was abrogated by anti-nepmucin mAbs that block either homophilic or heterophilic binding. Notably, the mAbs that inhibited homophilic binding blocked TEM without affecting lymphocyte adhesion. These results suggest that endothelial nepmucin promotes lymphocyte TEM using multiple adhesion pathways.
authors.affiliation: Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan.
authors.forename: Soojung
authors.initials: S
authors.lastname: Jin
authors.forename: Eiji
authors.initials: E
authors.lastname: Umemoto
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Tanaka
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Shimomura
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tohya
authors.forename: Keiji
authors.initials: K
authors.lastname: Kunizawa
authors.forename: Bo-Gie
authors.initials: BG
authors.lastname: Yang
authors.forename: Myoung Ho
authors.initials: MH
authors.lastname: Jang
authors.forename: Takako
authors.initials: T
authors.lastname: Hirata
authors.forename: Masayuki
authors.initials: M
authors.lastname: Miyasaka
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000276:immunology; D002465:Cell Movement; D004730:Endothelium, Vascular / Q000166:cytology / Q000276:immunology*; D007136:Immunoglobulins / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000276:immunology; D017434:Protein Structure, Tertiary; D052116:Sialomucins / Q000235:genetics / Q000276:immunology*; D022161:Transport Vesicles / Q000276:immunology
chemical_list: D007136:Immunoglobulins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D052116:Sialomucins; C512481:nepmucin, mouse