51 - Isolation and Characterization of Myogenic Stem Cells from Adult Skeletal Muscle

Abstract

This chapter discusses the methodologies commonly used in laboratory for isolating, culturing, and characterization of myogenic stem cells from adult skeletal muscle. The procedures have been modified from the initial studies on myogenic stem cells from fetal and adult chickens. The terms myogenic stem cell, myogenic precursor cell, and myogenic progenitor have often been used interchangeably to refer to the satellite cell. The presence of myogenic precursors in cell preparations from adult skeletal muscle has been investigated at the morphologic level based on the emergence of multinucleated myotubes in cultures prepared from these cell isolates. Myoblasts in the adult muscle are classically considered to be derived from quiescent cells located on the surface of the myofiber. These myofiber-associated cells were originally defined on the basis of their location beneath the myofiber basement membrane and thus termed satellite cells. However, it was not until the introduction of single myofiber cultures that direct evidence has been provided that the myofiber unit can yield myogenic cells, capable of fusing into myotubes, and that the source of these myogenic cells are the satellite cells. Satellite cells provide the adult muscle with a reserve capacity to replace differentiated, postmitotic cells required for maintaining myofiber integrity and muscle function—as such, the satellite cells have been considered tissue-specific stem cells.