Humanized endothelium in gene edited ETV2 null pig embryos as a platform for exogenic organ production and xenotransplantation. Sus scrofa

Whole organ transplantation is limited by the scarcity of donor organs. Xenotransplantation using large animals such as the pig may provide an unlimited number of transplantable organs for patients having chronic end-stage diseases and has received intense interest. One of the challenges associated with xenotransplantation is rejection triggered by donor endothelial cells. Therefore, we pursued a novel strategy, to generate pigs with humanized endothelial cells, which could be used as a universal platform for exogenic organ production and would reduce immune rejection. We used gene editing and somatic cell nuclear transfer technologies to engineer ETV2 mutant porcine embryos, which were lethal and lacked endothelial and hematopoietic lineages. The ETV2 porcine mutants were successfully complemented with GFP-labeled wild-type porcine blastomeres. The chimeric embryos were viable and all hematoendothelial lineages were populated by the donor-derived cells. Using embryo complementation strategies and hiPSCs, we demonstrated survival and proliferation of the chimeric embryos in vitro and observed engraftment of hiPSCs into the ETV2 mutant embryos in vivo.