Expanded CD133⁺ Cells from Human Umbilical Cord Blood Improved Heart Function in Rats after Severe Myocardial Infarction

Figure 4

Either purified CD133⁺ cells or expanded CD133⁺ cells decreased fibrosis and increased angiogenesis of rat hearts that underwent AMI. Representative photomicrographs of myocardial tissue sections in the infarct region of the three groups: control (a), transplanted with purified CD133⁺ cells (b), and expanded CD133⁺ cells (c). Control = control group, injected with isotonic saline solution (sodium chloride 0.9%). Purified = transplanted with purified CD133⁺ cells. Expanded = transplanted with expanded CD133⁺ cells. Semiquantitative analyses of cross-sectional areas were carried out to determine the level of fibrosis in the infarcted region of the heart (d) and the level of vascularization in the central/periphery regions of the heart (e) (for further details, see Materials and Methods). The control group presented less capillaries than the groups treated with CD133⁺ cells. The presence of many well-developed vessels was observed in animals transplanted with expanded CD133⁺ cells (white arrowheads in (c)). Structures resembling recently formed capillaries with one or without red blood cells were identified in rats transplanted with purified CD133⁺ cells (black arrowheads in (b)). The bars in graphs (d) and (e) represent the mean ± the standard error. Scale bars: 50 μm.

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