Fig. 7

Immunomodulatory effects of L-MSCs are mediated via secretion of PGE2. a L-MSCs were cultured in media containing the PGE2 inhibitor NS-398 overnight. CFSE-labeled PBMCs from unrelated pigs were co-cultured with MSCs in media containing PGE2 inhibitor NS-398. The cultures were stimulated with PHA (5 μg/ml). After 72 h, cell proliferation was analyzed by flow cytometry. A representative flow diagram is shown. b Percent change in cell proliferation in the presence or absence of PGE2 inhibitor (cultures of PBMCs only stimulated with PHA were considered as 100 %). Data are presented as % change in cell proliferation (mean ± SD) from MSCs/PBMCs isolated from three unrelated pig pairs. *P < 0.05. c Overnight cultures of L-MSCs and DCs were co-cultured with or without NS-398 and stimulated with LPS. TNF-α secretion in culture supernatants was detected by ELISA. Addition of PGE2 inhibitor resulted in a significant increase (P < 0.05) in TNF-α levels. Data are presented as mean ± SD of TNF-α levels in MSCs/DCs isolated from three unrelated pig pairs. *P < 0.05. d L-MSCs and PBMCs were co-cultured in media with or without NS-398. The cultures were stimulated with PHA and incubated for 24 h. IFN-γ production in culture supernatants was measured by ELISA. There was an increase in IFN-γ levels in cultures incubated with NS-398 PGE2. Data are presented as mean ± SD of IFN-γ levels in MSC/PBMC co-cultures isolated from three unrelated pig pairs. *P < 0.05. CFSE Carboxyfluorescein diacetate succinimidyl ester, DC Dendritic cell, IFN Interferon, MSC Mesenchymal stem cell, TNF Tumor necrosis factor