title: Activation of MKK4 (SEK1), JNK, and c-Jun in labial salivary infiltrating T cells in patients with Sjögren's syndrome.
abstract: We wanted to determine via immunohistochemistry, whether or not c-Jun NH2-terminal kinase (JNK) cascade is activated in labial salivary infiltrating T cells in patients with Sjögren's syndrome (SS). Six patients with primary SS were selected for this study. Phosphorylation of mitogen-activated protein kinase (MAPK) kinase 4 (MKK4) (SEK1), JNK, and c-Jun in salivary infiltrating T cells was studied using immunohistochemistry assay, including mirror section technique. Phosphorylated forms of MKK4, JNK, and c-Jun were detected in salivary infiltrating mononuclear cells. Expression of phosphorylated JNK was found in both CD4+ T cells and CD8+ T cells. Moreover, co-expression of phosphorylated JNK and c-Jun was demonstrated in the mirror sections. The results of this study suggest that the JNK cascade is activated in salivary infiltrating CD4+ T cells and CD8+ T cells in SS patients, which appears to contribute to the inflammatory salivary microenvironment of SS.
authors.affiliation: The First Department of Internal Medicine, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki City, Nagasaki, 852-8501, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Soejima
authors.forename: Hideki
authors.initials: H
authors.lastname: Nakamura
authors.forename: Mami
authors.initials: M
authors.lastname: Tamai
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawakami
authors.forename: Katsumi
authors.initials: K
authors.lastname: Eguchi
mesh_terms: D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007249:Inflammation / Q000503:physiopathology*; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D008875:Middle Aged; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D012469:Salivary Glands / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology; D012859:Sjogren's Syndrome / Q000276:immunology*
chemical_list: D016755:Proto-Oncogene Proteins c-jun; D048031:JNK Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4