title: Low number of memory B cells in the salivary glands of patients with primary Sjögren's syndrome.
abstract: We have previously shown that patients with primary Sjögren's Syndrome (pSS) show a significant reduction of autoantigen specific CD27(+) memory B cells and an abnormally elevated level of autoantibody producing plasma cells in peripheral blood (PB) compared to controls. Because both memory B cells and plasma cells have been detected in salivary glands (SG) of pSS patients, we aimed to study the B cell pattern in SG biopsies. Double immunohistochemical staining of CD20 and CD27 was carried out on paraffin-embedded SG tissue from 10 pSS patients to distinguish CD20(+)/CD27(+) memory B cells, and identify the CD20(+) glandular B cell zones (BCZ). Given that plasma blasts and plasma cells are CD27(++) and CD20(- ), additional CD138 single staining of serial sections allowed the distinction of CD27(++)/CD138(- ) plasma blasts located within the BCZ from CD27(++)/CD138(+) plasma cells that were found mostly on the periphery of the BCZ and also observed interstitially. Both BCZ and the memory B cell populations were then quantified. Contrary to what has been reported earlier through immunoflourescent staining of memory B cells in SG tissue, we have shown that there is a low number of memory B cells located within the glandular BCZ. Plasma blasts and plasma cells, however, were more abundant in the SG. Together our findings suggest that these low numbers of memory B cells in both PB and SG of pSS patients may be the result of activation of these cells into plasma cells at the site of inflammation.
authors: Broegelmann Research Laboratory, The Gade Institute, University of Bergen, Norway. Lara.Aqrawi@gades.uib.no
authors: Lara A
authors: LA
authors: Aqrawi
authors: Karl A
authors: KA
authors: Brokstad
authors: Kjerstin
authors: K
authors: Jakobsen
authors: Roland
authors: R
authors: Jonsson
authors: Kathrine
authors: K
authors: Skarstein
mesh_terms: D018951:Antigens, CD20 / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007156:Immunologic Memory; D010950:Plasma Cells / Q000276:immunology / Q000378:metabolism; D012469:Salivary Glands / Q000276:immunology* / Q000473:pathology*; D012859:Sjogren's Syndrome / Q000276:immunology* / Q000473:pathology*; D053668:Syndecan-1 / Q000378:metabolism; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000276:immunology
chemical_list: D018951:Antigens, CD20; D053668:Syndecan-1; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7