Fig. 10

TGF-β1 secreted by guinea pig MSCs contribute to enteric neuroprotection in vitro. a, a′ TGF-β1 secretion was assessed in gpBM-MSC and gpAT-MSC cultures. MSC-conditioned medium was collected after 48 h, and a bead-based cytometric analysis was performed. The mean fluorescence intensity (MFI) was recorded by flow cytometry, and a standard curve was generated to determine the concentration of MSC-secreted TGF-β1. Expansion medium without MSCs served as controls. *P <0.05, n = 6 independent cultures per group. b Primary myenteric neurons quantified within a 9-mm² area. Myenteric neurons were incubated with lipopolysaccharide (LPS) to mimic inflammatory conditions. Myenteric neurons were cultured with a combination of gpBM-MSCs or gpAT-MSCs, the TGF-βR1 inhibitor SB431542 (10 μM) or dimethyl sulfoxide as a vehicle control. ****P <0.0001, significantly different from untreated myenteric neurons; †P <0.05, †††P <0.001, significantly different from LPS + gpBM-MSCs + vehicle; ‡‡P <0.01, ‡‡‡P <0.001, significantly different from LPS + gpAT-MSCs + vehicle; n = 5 independent cultures per group. gpAT-MSC guinea pig adipose tissue-derived mesenchymal stem cell, gpBM-MSC guinea pig bone marrow-derived mesenchymal stem cell, MSC mesenchymal stem cell, TGF-β1 transforming growth factor-β1