Fig. 4

Gene expression of TGFB1 and TGFBR1 and release of TGFβ1. Mesangial cells (MCs) from patients with IgA nephropathy (IgAN) and controls were stimulated with IgA1 purified from blood from healthy controls (cIgA) or patients with IgAN (gd-IgA) or medium only for 6 h and the gene expression was investigated. Stimulation of control MCs and IgAN MCs with gd-IgA gave a significant increase in the gene expression of TGFB1 (gene coding for TGFβ1) (a). The gene expression for TGFBR1 (gene coding for TGF-beta receptor type-1) was not significantly affected by any of the treatments (b). IgAN MCs were stimulated with either cIgA or gd-IgA for 6 h and the release of TGFβ1into the cell culture medium was investigated. Both treatment with cIgA and gd-IgA resulted in an increased release of TGFβ1 compared to untreated cells (c). Grey bars represent control MCs, black bars represent IgAN MCs * P < 0.05, ** P < 0.01, ***P < 0.001, error bars represent SEM