01). Conclusion: Our studies confirmed the role of Gd-IgA1-IgG IC in the pathogenesis of IgAN and induction of proteinuria and hematuria.

Furthermore, the Gd-IgA1-IgG IC may bind to glomerular endothelial cells and induce release of pathogenic cytokines and chemokines. SUZUKI HITOSHI1, SUZUKI YUSUKE1, MAKITA YUKO1, YANAGAWA HIROYUKI1, JULIAN BRUCE A2,3, NOVAK JAN3, TOMINO YASUHIKO1 1Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine; 2Departments of Medicine, this website University of Alabama at Birmingham; 3Departments of Microbiology, University of Alabama at Birmingham Introduction: IgA1 in circulating immune complexes and mesangial deposits of patients with IgA nephropathy (IgAN) is aberrantly glycosylated, galactose-deficient in O-glycans (Gd-IgA1), and is bound to anti-glycan IgG/IgA autoantibodies. However, the origin of cells producing Gd-IgA1 and the autoantibodies is not certain. Upper respiratory tract infections and tonsillitis are frequently associated with clinical presentation and exacerbation of IgAN, suggesting a link with disease pathogenesis. In some patients, tonsillectomy and glucocorticoids (TSP) may slow disease progression MK-1775 price in early clinical stages. Therefore, we assessed whether

tonsillar cells produce Gd-IgA1 or anti-glycan autoantibodies. Methods: Tonsillar

cells obtained from 29 patients with IgAN were cultured 72 hours. Gd-IgA1 and anti-glycan IgG secreted by these cells were measured by ELISA. Proteinuria and hematuria, and serum levels of Gd-IgA1, Gd-IgA1-specific IgG and IgA, and IgG-IgA immune complexes (IC) were measured before and Ribose-5-phosphate isomerase after TSP. Results: Proteinuria and hematuria improved after TSP (P < 0.05). Eighteen of 29 patients had proteinuria less 0.3 g/g and 5 red blood cells/HPF after TSP (Remission group). Eleven patients did not clinically improve (non-Remission group). Serum levels of Gd-IgA1, Gd-IgA1-specific autoantibodies, and IgG-IgA IC decreased during glucocorticoid therapy after tonsillectomy (P < 0.01). The rates of decrease in the levels of Gd-IgA1, Gd-IgA1-specific antibodies and IgG-IgA IC were greater in the Remission group (P < 0.01). Tonsillar cells from Remission group produced more Gd-IgA1 and anti-glycan IgG than those from non-Remission group (P < 0.01). Conclusion: Tonsillar cells may contribute to the circulating Gd-IgA1 and anti-glycan IgG in patients with IgAN. These biomarkers may be useful for guiding therapy of IgAN. YAMADA KOSHI1,2, HUANG ZHI-QIANG1, RASKA MILAN1,3, REILY COLIN R.1, SUZUKI HITOSHI1,2, MOLDOVEANU ZINA1, KIRYLUK KRZYSZTOF4, SUZUKI YUSUKE2, TOMINO YASUHIKO2, GHARAVI ALI G.4, WILLEY CHRISTOPHER D.1, JULIAN BRUCE A.