title: Expression of Janus kinase 3 in human endothelial and other non-lymphoid and non-myeloid cells.
abstract: Members of the Janus kinase (Jak) family of protein tyrosine kinases have recently been implicated in the proximal signal transduction events of cytokine receptors. Jak3, a newly discovered member of this family, is believed to be normally limited in its expression to cells of the lymphoid and myeloid lineages. Herein we show that Jak3 is expressed in primary human vascular cells, as well as other non-lymphoid and non-myeloid cell types. Reverse transcriptase-polymerase chain reaction and Northern blot analysis revealed that Jak3 mRNA was expressed at low levels in human umbilical vein endothelial cells (HUVEC), human aortic smooth muscle cells (HASMC), A549 (human lung carcinoma), and DLD-1 (human colon adenocarcinoma) cells. Higher basal levels of Jak3 mRNA were detected in HMEC-1 (human microvascular cell line) and HepG2 (human hepatocellular carcinoma) cells. Jak3 mRNA expression was induced in HUVEC, HMEC-1, and HASMC by treatment with interleukin-1beta, tumor necrosis factor-alpha, interferon-gamma, and lipopolysaccharide. Jak3 protein was detectable at low levels in untreated HMEC-1, and these levels increased significantly with cytokine treatment. Furthermore, Jak3 protein was phosphorylated upon treatment of these cells with interleukin-4. This work shows that Jak3 is expressed or inducible in human vascular endothelial, vascular smooth muscle, and other non-lymphoid and non-myeloid cells, suggesting a broader role for Jak3 in the cytokine signal transduction of these cells.
authors.affiliation: Departments of Medicine and Pathology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Verbsky
authors.forename: E A
authors.initials: EA
authors.lastname: Bach
authors.forename: Y F
authors.initials: YF
authors.lastname: Fang
authors.forename: L
authors.initials: L
authors.lastname: Yang
authors.forename: D A
authors.initials: DA
authors.lastname: Randolph
authors.forename: L E
authors.initials: LE
authors.lastname: Fields
mesh_terms: D000595:Amino Acid Sequence; D006528:Carcinoma, Hepatocellular / Q000201:enzymology; D002460:Cell Line; D016384:Consensus Sequence; D004730:Endothelium, Vascular / Q000201:enzymology*; D004790:Enzyme Induction; D015870:Gene Expression; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology; D053616:Janus Kinase 3; D008113:Liver Neoplasms / Q000201:enzymology; D008214:Lymphocytes / Q000201:enzymology*; D008833:Microcirculation; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000201:enzymology*; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D012333:RNA, Messenger; D015847:Interleukin-4; D011505:Protein-Tyrosine Kinases; C507933:JAK3 protein, human; D053616:Janus Kinase 3