Expression of B1a cells and IgA1 positive cells in tonsil of IgA nephropathy patients and analysis of associated clinicopathological factors / 中华肾脏病杂志

ABSTRACT

Objective To examine the expression of IgA1 and B1a positive cells in palatine tonsils of IgA nephropathy (IgAN) patients, and to analyze the association between B1a cells and clinicopathological changes. Methods Eight patients diagnosed as IgAN by renal biopsy and 8 chronic tonsillitis patients without nephritis as control were enrolled in the study.Immunofluorescence and laser scanning confocal microscope (LSCM) were applied to observe the localization and quantitative calculation of Bla and IgA1 positive cells. Statistic analysis of the association of B1a cells with proteinuria and pathological Lee's grading was performed. Results Bla cells were mainly localized in germinal center of tonsil, and IgA1 positive cells were mainly localized in subepithelium of tonsil. Compared to control group, the percent of B1a cells and IgA1 positive cells was significantly higher in IgAN (P＜0.01). There was a positive correlation between Bla cells and IgA1 cells (P＜0.05). In IgAN, the percent of B1a cells in patients with hematuria and proteinuria was obviously higher than that of patients with hematuria only (P＜0.05). The number of Bla cells in IgAN patients with≥Lee's grade Ⅲ was significantly higher than that of those ＜ grade Ⅲ (P＜0.05). Conclusions IgA1 may be secreted by Bla cells in the tonsil of IgAN patients. The number of B1a cells is correlated with exacerbation of proteinuria and pathological severity, which may play an important role in pathogenesis of IgAN.