Humanized skeletal muscle in MYF5/MYOD/MYF6-null pig embryos

Interspecies chimeras as a platform for exogenic organ production and transplantation

“…The analysis of the intraspecies chimeric skeletal muscle demonstrated that that the one-month old piglets had normal growth, normal ambulation, and normal skeletal muscle physiological function (Figure 4). 49 Histological assessment verified that every muscle fiber was GFP positive, whereas the neuronal and the vascular elements did not express GFP (Figure 4). Having established these chimeric results, complementation and SCNT strategies were used to generate interspecies chimeras.…”

“…Recent studies by Maeng et al. 49 in the Garry laboratories further examined intraspecies and interspecies complementation in order to engineer humanized muscle in gene-edited pigs. In these studies, the Garry laboratories engineered pig embryos that lacked native skeletal muscle by deleting Myogenic Factor 5/Myogenic Differentiation 1/Myogenic Factor 6 ( MYF5/MYOD/MYF6 ) genes using a multiplex gene editing strategy.…”

“…In these studies, the Garry laboratories engineered pig embryos that lacked native skeletal muscle by deleting Myogenic Factor 5/Myogenic Differentiation 1/Myogenic Factor 6 ( MYF5/MYOD/MYF6 ) genes using a multiplex gene editing strategy. 49 These mutant porcine embryos were rescued by complementing them with GFP-labeled porcine blastomeres. These intraspecies chimeras were viable.…”

“…In these studies, donor GFP-TP53 null hiPSCs cells were used to complement the MYF5/MYOD/MYF6 null porcine morula and the chimeric embryos were surgically delivered to surrogate gilts. 49 These interspecies chimeras were harvested at approximately E30 and demonstrated that all the skeletal muscle was of human origin (Figure 4). 49 Extensive analysis verified that no human cells or their derivatives were associated with brain or the germ cell lineages in the chimeric embryos.…”

“…49 These interspecies chimeras were harvested at approximately E30 and demonstrated that all the skeletal muscle was of human origin (Figure 4). 49 Extensive analysis verified that no human cells or their derivatives were associated with brain or the germ cell lineages in the chimeric embryos. 49 These studies used multiple techniques to validate the results and importantly the results supported the notion that increased efficiency of chimeric organs could be achieved through targeted expression or deletion of selected genes.…”