Figure 1.
MSCs suppressed both naïve and pre-activated T cell proliferation in a time and dose-dependent manner. 5 × 105 BALB/c splenocytes and 5 × 105 C57BL/6 splenocytes were used as either stimulators or responders in MLR. (A) BALB/c or C57BL/6 MSCs were added to MLR at the start of the reaction, and the ratios of splenocytes to MSCs were 2,000:1, 200:1 or 20:1. The culture periods were 24 h, 48 h and 72 h. (B) BALB/c or C57BL/6 MSCs were added to the MLR at 36 h after the start of the reaction. The ratio of splenocytes to MSCs was 20:1. The culture continued for 24 h, 36 h, 48 h or 72 h. The results are expressed as the mean counts per minute (cpm) ± SD for three independent experiments.