The TGF-β1 Signaling Pathway as an Attractive Target in the Fibrosis Pathogenesis of Sjögren’s Syndrome

Figure 6

(a) Western blot analysis of TGF-β1/SMAD/Snail and of the mesenchymal markers E-cadherin, vimentin, and collagen type I in cultured untreated SGCE, TGF-β1- (10 ng/ml-) treated healthy SGEC for 48 hours, and pSS SGEC. Lane 1: healthy control SGEC, lane 2: TGF-β1-treated healthy SGEC, and lane 3: pSS SGEC. Protein expressions were quantified using ImageJ software (b). The data are expressed as relative intensity of proteins normalized to β-actin expression. Values are considered statistically significant at or . In concordance with the RT-PCR and real-time PCR data, in TGF-β1-treated healthy SGEC, a significant increase of total SMAD 2/3, pSMAD 2/3, SMAD 4, SNAIL, vimentin, and collagen type I band intensity was observed in comparison with untreated control healthy SGEC, while epithelial marker E-cadherin band intensity was reduced compared with untreated control SGEC. In addition, Western blot images related to pSS SGEC completely overlapped with Western blot results obtained from healthy SGEC stimulated with the TGF-β1. Immunoblotting gave rise to bands of the expected size. All Western blots were repeated a minimum of three times.

(a)

(b)