title: G1/S cell cycle arrest provoked in human T cells by antibody to CD26.
abstract: CD26 is T cell costimulatory molecule with dipeptidyl peptidase IV (DPPIV) enzyme activity located in its extracellular region. The expression of CD26 is enhanced after activation of T cells, while it is preferentially expressed on a subset of CD4+ memory T cells in the resting state. In this paper, we demonstrate that binding of the soluble anti-CD26 monoclonal antibody (mAb) 1F7 inhibits human T-cell growth and proliferation in both CD26-transfected Jurkat T-cell lines and human T-cell clones by inducing G1/S arrest, which is associated with enhancement of p21Cip1 expression. This effect depends on the DPPIV enzyme activity of the CD26 molecule. Moreover, we show that expression of p21Cip1 after treatment with the anti-CD26 mAb 1F7 appears to be induced through activation of extracellular signal-regulated kinase (ERK) pathway. These data thus suggest that anti-CD26 treatment may have potential use in the clinical setting involving activated T cell dysregulation, including autoimmune disorders and graft-vs.-host disease.
authors.affiliation: Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Ohnuma
authors.forename: Tomonori
authors.initials: T
authors.lastname: Ishii
authors.forename: Satoshi
authors.initials: S
authors.lastname: Iwata
authors.forename: Osamu
authors.initials: O
authors.lastname: Hosono
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawasaki
authors.forename: Masahiko
authors.initials: M
authors.lastname: Uchiyama
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Tadanori
authors.initials: T
authors.lastname: Yamochi
authors.forename: Nam H
authors.initials: NH
authors.lastname: Dang
authors.forename: Chikao
authors.initials: C
authors.lastname: Morimoto
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D018929:Cell Culture Techniques; D002455:Cell Division / Q000276:immunology; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000378:metabolism; D018819:Dipeptidyl Peptidase 4 / Q000276:immunology*; D016193:G1 Phase / Q000276:immunology*; D006801:Humans; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000276:immunology; D020935:MAP Kinase Signaling System / Q000276:immunology; D016196:S Phase / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D018819:Dipeptidyl Peptidase 4