title: Isthmin 1 is a secreted protein expressed in skin, mucosal tissues, and NK, NKT, and th17 cells.
abstract: Using a comprehensive microarray database of human gene expression, we identified that in mammals, a secreted protein known as isthmin 1 (ISM1) is expressed in skin, mucosal tissues, and selected lymphocyte populations. ISM1 was originally identified in Xenopus brain during development, and it encodes a predicted ∼50-kDa protein containing a signal peptide, a thrombospondin domain, and an adhesion-associated domain. We confirmed the pattern of expression of ISM1 in both human and mouse tissues. ISM1 is expressed by DX5(+) lung lymphocytes that include NK and NKT-like cells, and is also expressed by some CD4(+) T cells upon activation but its expression increases significantly when CD4(+) T cells were polarized to the Th17 lineage in vitro. The presence of IFN-γ during CD4(+) T cell polarization inhibits ISM1 expression. Given that ISM1 has been reported to have anti-angiogenic properties, these observations suggest that ISM1 is a mediator of lymphocyte effector functions and may participate in both innate and acquired immune responses.
authors: 1 Department of Physiology and Biophysics, School of Medicine, University of California , Irvine, Irvine, California.
authors: Ricardo
authors: R
authors: Valle-Rios
authors: José L
authors: JL
authors: Maravillas-Montero
authors: Amanda M
authors: AM
authors: Burkhardt
authors: Cynthia
authors: C
authors: Martinez
authors: Bettina Alexandra
authors: BA
authors: Buhren
authors: Bernhard
authors: B
authors: Homey
authors: Peter Arne
authors: PA
authors: Gerber
authors: Octavio
authors: O
authors: Robinson
authors: Peter
authors: P
authors: Hevezi
authors: Albert
authors: A
authors: Zlotnik
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D019295:Computational Biology; D005786:Gene Expression Regulation; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D007371:Interferon-gamma / Q000378:metabolism; D007694:Killer Cells, Natural / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D046228:Microarray Analysis; D009092:Mucous Membrane / Q000276:immunology; D055611:Natural Killer T-Cells / Q000276:immunology*; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012867:Skin / Q000276:immunology*; D058504:Th17 Cells / Q000276:immunology*; D019699:Thrombospondins / Q000235:genetics / Q000378:metabolism*
chemical_list: C000598687:ISM1 protein, human; D036341:Intercellular Signaling Peptides and Proteins; D011506:Proteins; D019699:Thrombospondins; C571340:isthmin protein, mouse; D007371:Interferon-gamma