Anti-PAX7 (aa 456-520) polyclonal antibody

CD133+ cells are potential myogenic progenitors for skeletal muscle regeneration to treat muscular dystrophies. The proliferation of human CD133+ stem cells was studied for 14 days in 3D biomimetic electrospun poly-L-lactic acid (PLLA) nano-fiber scaffolds. Additionally, the myogenic differentiation of the cells was studied during the last 7 days of the culture period. The cells were homogeneously distributed in the 3D scaffolds while colony formation and myotube formation occurred in 2D. After a lag phase due to lower initial cell attachment and an adaptation period, the cell growth rate in 3D was comparable to 2D after 7 and 14 days of culture. The expression of the stem cell (SC) marker PAX7 was 1.5-fold higher in 3D than 2D while the differentiation markers MyoG, Desmin and MyoD were only slightly changed (or remain unchanged) in 3D but strongly increased in 2D (12.6, 3.9, and 7.9-fold), and the myotube formation observed in 2D was absent in 3D. The marker expression during proliferation and differentiation, together with the absence of myotubes in 3D, indicates a better maintenance of stemness in 3D PLLA and stronger tendency for spontaneous differentiation in 2D culture. This makes 3D PLLA a promising biomaterial for the expansion of functional CD133+ cells.

The objective of this study was to investigate the effects of mesenchymal cells on myoblasts in long-term cultivation of myoblast cell sheets. Sheets of myoblasts and mesenchymal cells from Japanese rabbit oral mucosa were generated and analyzed by histochemistry, Western blot, and reverse transcription-polymerase chain reaction. The presence of desmin and type IV collagen, which is seen in normal muscle tissue, was also confirmed in all the sheets produced. Expression of desmin and type IV collagen showed a decrease under co-culture conditions. In addition, expression of genes important in maintaining the undifferentiated state (Pax7, CD34, myogenin, MyoD) in myoblasts was observed throughout the long cultivation period. Insulin-like growth factor was expressed only when the mesenchymal cells were co-cultured with myoblasts. These data suggest that the presence of mesenchymal cells in a long-term co-culture system influences myoblast differentiation.