title: Increase of Intracellular BAFF in B Cells of Sjögren's Patients Is Not Affected by Decrease of BAFFR.
abstract: The presence of a broad spectrum of autoantibodies in Sjögren's syndrome (SjS) patients is the result of abnormal B-cell regulation that can be at least partially explained by abnormal BAFF/BAFFR regulation. The objective of this study was to determine both membrane and intracellular expression of BAFF/BAFFR in monocytes and B-cells in peripheral blood of 19 primary Sjögren's syndrome patients and 20 healthy controls using flow cytometry. We also measured sBAFF in serum. Compared to healthy controls, both surface and intracellular expression of BAFF was significantly increased in monocytes and B-cells of SjS patients. Also serum sBAFF level was elevated. Expression of BAFFR on B-cells of SjS patients was surprisingly decreased, but there was no clear increase or decrease within monocytes. Our results indicate that activated monocytes communicate with B-cells via BAFF and BAFFR, so that B-cells are stimulated, but BAFF is also produced to stimulate cells in autocrine way. The decrease of BAFFR expression in SjS patients suggests that there is the mechanism that attempts to take over in order to balance the high level of BAFF.
authors.affiliation: Charles University in Prague, Faculty of Medicine and University Hospital in Hradec Králové, Department of Clinical Immunology and Allergology, Czech Republic. jan.krejsek@fnhk.cz.
authors.forename: Jan
authors.initials: J
authors.lastname: Krejsek
authors.affiliation: Charles University in Prague, Faculty of Medicine and University Hospital in Hradec Králové, Department of Clinical Immunology and Allergology, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Koláčková
authors.affiliation: Charles University in Prague, Faculty of Medicine and University Hospital in Hradec Králové, Department of Stomatology, Czech Republic.
authors.forename: Irena
authors.initials: I
authors.lastname: Lindrová
authors.affiliation: Charles University in Prague, Faculty of Medicine and University Hospital in Hradec Králové, Department of Stomatology, Czech Republic.
authors.forename: Radovan
authors.initials: R
authors.lastname: Slezák
authors.affiliation: Charles University in Prague, Faculty of Medicine and University Hospital in Hradec Králové, Department of Clinical Immunology and Allergology, Czech Republic.
authors.forename: Ctirad
authors.initials: C
authors.lastname: Andrýs
mesh_terms: D053264:B-Cell Activating Factor / Q000096:biosynthesis* / Q000097:blood; D053265:B-Cell Activation Factor Receptor / Q000096:biosynthesis*; D001402:B-Lymphocytes / Q000378:metabolism*; D005260:Female; D006801:Humans; D007424:Intracellular Fluid; D007425:Intracellular Membranes; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D012859:Sjogren's Syndrome / Q000378:metabolism*
chemical_list: D053264:B-Cell Activating Factor; D053265:B-Cell Activation Factor Receptor; C435926:TNFRSF13C protein, human; C505719:TNFSF13B protein, human
keywords: BAFF; BAFFR; Sjögren’s syndrome; intracellular expression; sBAFF