Change in undifferentiated stem cell morphology and proliferation after time in culture.

<p>(<b>A</b>) Undifferentiated MSC showed spindle shaped morphology at T2 but cells from old donors show a bigger more flattered shape at T12. <b>(B</b>) uMSC were cultured for nine weeks and passaged and counted on a weekly basis. Cumulative population doublings were calculated and plotted against time.