Fig 5.

Inhibitory effect of MSC on lymphocyte proliferation in MLC. hPBMC from healthy donors were co-cultured in one-way MLC with irradiated allogeneic PBMC in the absence (control) or presence of decreasing number of unrelated MSC. At 96 hrs of culture, cells were stained for intracellular Ki-67 antigen. Ki-67 antigen positivity indicates proliferating responder cells. Bars represent the percentage of Ki-67⁺ cells in three independent experiments at 3 MSC to effector ratios of 1, 0.5 and 0.1.