kB is overexpressed in proteinuric patients with IgA nephropathy

Increasing evidence suggests that nuclear factor kB (NF-kB) plays a pivotal role in many glomerulop- athies. Therefore, the aim of the present study was to determine the tubular immunoexpression of NF-kB in non-proteinuric (n = 22) and proteinuric patients (n = 16) with IgA nephropathy (IgAN). Another purpose of this study was to examine the possible relationship between NF-kB immunoexpression and proteinuria, intersti- tial fibrosis as well as interstitial infiltrates. Tubular immunoexpression of NF-kB, interstitial monocytes/mac- rophages, T lymphocytes, B lymphocytes and interstitial area were determined using a computer image analysis system. The mean values of the tubular immunoexpression of NF-kB, interstitial area and interstitial mono- cytes/macrophages were in proteinuric IgAN patients significantly increased compared to non-proteinuric IgAN cases, whereas interstitial T and B lymphocytes did not differ between these groups. In proteinuric patients, tubular immunoexpression of NF-kB was highly significantly positively correlated with the degree of proteinur- ia. Moreover, in both the non-proteinuric and the proteinuric groups with IgAN, tubular immunoexpression of NF-kB was positively correlated with the interstitial area and interstitial monocytes/macrophages. Our findings raise the possibility that proteinuria causes tubular overexpression of NF-kB and, in the process, recruitment of monocytes/macrophages and tubulointerstitial injury in IgAN patients. (Folia Histochemica et Cytobiologica 2012, Vol. 50, No. 1, 93-98)