Fig. 3. (A) Efficiency of dystrophin restoration in mdx gastrocnemius muscle by myogenic precursor populations at 7 days following injection. CD34 and Sca-1 sorted LP subpopulations were obtained from separate isolations. A regenerative index, comparing restoration of dystrophin on a per cell basis (desmin-positive cells), was used for a more effective comparison of the various populations. CD34-positive LP cells demonstrated the highest dystrophin restoration (^*P<0.05, CD34-positive vs. EP and CD34-negative). Cryosections taken from mdx muscle following transplantation and immunochemically stained to reveal dystrophin expression following injection of EP (B; 220,000 myogenic cells) and CD34-negative and - positive cells (C,D; approximately 95,000 myogenic cells each) are shown (20x objective).