title: Type II Natural Killer T Cells that Recognize Sterol Carrier Protein 2 Are Implicated in Vascular Inflammation in the Rat Model of Systemic Connective Tissue Diseases.
abstract: We previously generated a rat model that developed systemic connective tissue diseases, including synovitis, myositis, and small-vessel vasculitis (SVV), and established a vascular endothelial cell-reactive T-cell clone, VASC-1, from the model. VASC-1 was determined to be a type II natural killer T-cell clone. In this study, we attempted to identify the antigen recognized by VASC-1. The monkey-derived cell line COS-7 was used because VASC-1 does not bind naturally to COS-7, although the amino acid sequences are well conserved between monkey CD1d and rat CD1d. We generated 98 COS-7 clones transfected with miscellaneous rat cDNA and screened them for VASC-1 binding. Consequently, we found one clone, 4D2, which could bind to VASC-1. Sequencing identified the rat cDNA introduced into 4D2 as sterol carrier protein 2 (SCP2). When VASC-1 was co-cultured with SCP2 knockdown rat vascular endothelial cells, VASC-1 binding was reduced significantly. Moreover, we designed a series of rat SCP2 peptides and introduced them into COS-7 cells. On the basis of VASC-1 binding and proliferation, we revealed that the peptide rSCP2518-532included the epitope recognized by VASC-1. Furthermore, immunization with rSCP2518-532accelerated the development of SVV in the rat model. The collective findings suggest that type II natural killer T cells reactive with autologous SCP2 are implicated in vascular inflammation in the rat model.
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nishioka
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Madoka
authors.initials: M
authors.lastname: Yamaguchi
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Kawakami
authors.affiliation: Undergraduate School of Health Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Maya
authors.initials: M
authors.lastname: Munehiro
authors.affiliation: Faculty of Health Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Sakiko
authors.initials: S
authors.lastname: Masuda
authors.affiliation: Department of Pathology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Utano
authors.initials: U
authors.lastname: Tomaru
authors.affiliation: Faculty of Health Sciences, Hokkaido University, Sapporo, Japan. Electronic address: aishizu@med.hokudai.ac.jp.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ishizu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D055610:Antigens, CD1d / Q000378:metabolism; D019556:COS Cells; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D002522:Chlorocebus aethiops; D003240:Connective Tissue Diseases / Q000378:metabolism* / Q000473:pathology*; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000378:metabolism; D000939:Epitopes / Q000378:metabolism; D006801:Humans; D007114:Immunization; D007249:Inflammation / Q000378:metabolism / Q000473:pathology*; D008954:Models, Biological; D055611:Natural Killer T-Cells / Q000276:immunology*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D014162:Transfection; D014652:Vascular Diseases / Q000378:metabolism / Q000473:pathology*; D014682:Vena Cava, Inferior / Q000378:metabolism
chemical_list: D055610:Antigens, CD1d; D002352:Carrier Proteins; D000939:Epitopes; D010455:Peptides; C072087:sterol carrier proteins