Figure 1. Morphological appearance of hUC-MSCs.

A: After 4d of culture, two types of adherent cells were observed: a population of small flattened cells morphologically similar to the endothelial cells (black rectangle), and a population of spindle-shaped fibroblast-like cells (magnification×100); B: On 7 to 10d after initial plating, the cells began to appear as long spindle-shaped fibroblastic cells, began to form colonies and became confluent (magnification×100); C: The appearance of hUC-MSCs during the 10^th passage. The cells retained their proliferative potential with long passages (magnification×100).