Skeletal muscle tissue engineering: which cell to use?

Tissue-engineered skeletal muscle is urgently required to treat a wide array of devastating congenital and acquired conditions. Selection of the appropriate cell type requires consideration of several factors which amongst others include, accessibility of the cell source, in vitro myogenicity at high efficiency with the ability to maintain differentiation over extended periods of time, susceptibility to genetic manipulation, a suitable mode of delivery and finally in vivo differentiation giving rise to restoration of structural morphology and function. Potential stem-progenitor cell sources include and are not limited to satellite cells, myoblasts, mesoangioblasts, pericytes, muscle side-population cells, CD133(+) cells, in addition to embryonic stem cells, mesenchymal stem cells, amniotic fluid stem cells and induced pluripotent stem (iPS) cells. The relative merits and inherent limitations of these cell types within the field of tissue-engineering are discussed in the light of current research. Recent advances in the field of iPS cells should bear the fruits for some exciting developments within the field in the forthcoming years.