Figure 4

Effects of Fas ligand levels in mesenchymal stem cells on multiple myeloma cells under co-culture. (A) Comparison of Fas ligand (Fas-L) expression in mesenchymal stem cells (MSCs) after aspirin treatment. (B) Multiplication of multiple myeloma (MM) cells under co-culture condition with MSCs that express different levels of Fas-L. For the graph, the number of MM co-cultured without MSCs (Cont.), with normal MSCs (Co-cul), with MSCs from generalized lymphoproliferative disease mice (Co-cul(gld)) or with MSCs treated with any aspirin (Co-cul(Asp)) were counted after 0, 6, 12 or 24 hours. (C) Apoptotic analysis of MM cells under co-culture condition with MSCs expressing different levels of Fas-L (detected and quantified through fluorescence-activated cell sorting (FACS): x axis, Annexin V; y axis, 7AAD-positive cells). Data presented as mean ± standard deviation (SD) for two parallel experiments. #P <0.05 versus Con. (D) Expression levels of cleaved caspase-3 in MM cells with or without co-cultured MSCs (expressing different levels of Fas-L) at 0, 6, 12, and 24 hours. (E) Rates of apoptotic MM under co-culture with MSCs (expressing different levels of Fas-L). Data presented as mean ± SD for two parallel experiments. #P <0.05 versus the control group (Con.). CFSE, carboxyfluorescein diacetate, succinimidyl ester; DAPI, 4′,6-diamidino-2-phenylindole.