Generation of human myogenic cell lines by the transformation of primary culture with origin-defective SV40 DNA.

The gene transfection technique was applied to establish clonal human skeletal muscle cell lines. DNA of a replication origin-defective mutant of SV40 was transfected into a primary culture of human skeletal muscle by the DNA-calcium phosphate co-precipitation method, and myoblast-derived cells were selected from among the transformed cells and cloned. The myogenic clonal cells exhibited an enhanced growth rate and an unlimited life span, which indicated that a stable supply of a large quantity of cultured human myogenic cells without contaminating fibroblasts was possible. In addition, despite the transformation, the transformed clones retained a certain differentiation ability, that is, they could form multinucleated cells or express a muscle-specific isomer of creatine kinase. These characteristics of transformed myogenic cells should be of great value in studies on the molecular pathologies of various myopathies.