TLR2 expression and localization in renal biopsy specimens of patients with obstructive hydronephrosis (B), severe forms of IgA nephropathy (C, D) or in control renal biopsy specimens (A).

<p>TLR2 was clearly upregulated in kidneys of patients with obstructive hydronephrosis or IgA nephropathy and mainly expressed by tubulointerstitial cells. Some expression was found at the apical side of renal tubules (asterisks, D). Double staining showed coexpression of various myofibroblasts (blue) (asterisks E), and numerous macrophages (blue) with TLR2 (red) (asterisks F). No immunoreactivity of TLR2 was observed in negative control sections derived from IgA nephropathy patients (insert A, primary antibody omitted).