title: In Sjögren's syndrome, B lymphocytes induce epithelial cells of salivary glands into apoptosis through protein kinase C delta activation.
abstract: Sjögren's syndrome (SS) is a chronic autoimmune epithelitis associated with diffuse lymphocytic infiltration that varies in composition and differs according to lesion severity. T lymphocytes have been viewed as competent in their own right in the destruction of epithelial cells, whereas B lymphocytes that predominate in severe lesions have never been implicated in direct tissue damage. Using co-culture experiments with human salivary gland (HSG) cell line cells and tonsilar B lymphocytes, we observed that direct HSG cell-B lymphocyte contacts were able to induce apoptosis in epithelial cells. This B lymphocyte-mediated cell death could not be ascribed to Fas-Fas ligand interactions but required translocation of protein kinase C delta (PKC δ) into the nucleus of epithelial cells. Ultimately, activation of PKCδ resulted in histone H2B phosphorylation on serine 14 and poly (ADP-ribose) polymerase cleavage. Our results suggest that B lymphocytes infiltrating the SGs of patients with SS could evoke epithelial cell apoptosis.
authors: Research Unit "Immunology & Pathology", European University of Brittany, and Brest University Medical School Hospital, Brest, France.
authors: Marie-Michèle
authors: MM
authors: Varin
authors: Thomas
authors: T
authors: Guerrier
authors: Valérie
authors: V
authors: Devauchelle-Pensec
authors: Christophe
authors: C
authors: Jamin
authors: Pierre
authors: P
authors: Youinou
authors: Jacques-Olivier
authors: JO
authors: Pers
mesh_terms: D021581:Active Transport, Cell Nucleus; D017209:Apoptosis; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D002648:Child; D018920:Coculture Techniques; D004789:Enzyme Activation; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D006657:Histones / Q000378:metabolism; D006801:Humans; D010766:Phosphorylation; D051745:Protein Kinase C-delta / Q000378:metabolism*; D012469:Salivary Glands / Q000473:pathology; D012859:Sjogren's Syndrome / Q000276:immunology*
chemical_list: D006657:Histones; D051745:Protein Kinase C-delta