Figure 4.

MSC CM suppresses apoptosis of lung epithelial cells. (A): Gating strategy; (B): Representative FACS plots; and (C): Quantification of apoptosis assay examining the ability of MSC CM to inhibit alveolar epithelial apoptosis. Apoptosis was measured by double staining of annexin V and PI and measured by flow cytometry. MSC CM significantly reduced epithelial apoptosis induced by cisplatin. This effect was lost when CM from HGF knockdown cells was used. CM from nonsilencing controls caused no significant difference. Data are representative of three experiments in B and n = 3 for C. Bar graph presents the % of early apoptotic cells (lower right quadrant: annexin V⁺ PI^-) as mean ± standard error of the mean. ∗, p < .05; ∗∗, p < .01. Abbreviations: CM, conditioned media; HGF, hepatocyte growth factor; MSC, mesenchymal stromal cell; Non Sil Ctrl, nonsilencing control; PI, propidium iodide; shHGF, shRNA HGF knockdown.