Figure 3.

MSC culture supernatant caused apoptosis of splenocytes rather than cell cycle arrest. 5 × 10⁵ BALB/c splenocytes were stimulated with anti-CD3 (3 µg/ml) and CD28 (1 µg/ml) antibodies for 72 h. (A) 100 µl MSC culture supernatant or 2.5 × 10⁴ MSCs were treated in the indicated groups. DNA content was assessed using PI staining. (B) 2.5 × 10⁴ MSCs were added to the proper group. Apoptotic cells were stained with annexin V (PE) and SYTOX® green. These assays were analyzed using flow cytometry, and MSCs were excluded from the analysis by positive gating of CD45. One representative of three separate experiments is shown.