The effect of Rapa on CD34⁺ cells and CD34⁺-derived DCs.

(A) CD34⁺ cells were cultured for 6 days in the absence or presence of 10⁻⁷ M Rapa. The cells were then harvested and analyzed for their proliferation by counting the cells using trypan blue exclusion. Data represented are the mean (± SD) fold of proliferation of 2 different donors. (B) Freshly isolated cord blood CD34⁺ cells were cultured for 6 days in the absence or presence of 10⁻⁷ M Rapa. Differentiation was followed by FACS analysis using anti-CD14 and anti-CD1a directly conjugated antibodies. The results are representative of 2 independent experiments. (C) CD34⁺-derived DCs were harvested on day 6 and subsequently cultured in the presence of GM-CSF with or without 10⁻⁷ M Rapa for 15 or 38 hours. Apoptosis was detected by flow cytometry using annexin V/PI staining. The results shown for both time points are representative of 2 independent experiments.