Generation of insulin-like growth factor 1 receptor-knockout pigs as a potential system for interspecies organogenesis

• Published in: Regenerative therapy Vol. 26; pp. 783 - 791
• Main Authors: Nagaya, Masaki, Uchikura, Ayuko, Nakano, Kazuaki, Watanabe, Masahito, Matsunari, Hitomi, Umeyama, Kazuhiro, Mizuno, Naoaki, Nishimura, Toshiya, Nakauchi, Hiromitsu, Nagashima, Hiroshi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2024; Japanese Society for Regenerative Medicine; Elsevier
• Subjects: Blastocyst complementation techniques; Growth retardation; Insulin-like growth factor 1 receptor; Original; Pig; GH; CRISPR/Cas9; KO; RPKM; Blastocyst complementation techniques; Insulin-like growth factor 1 receptor; IGF1; Growth retardation; gRNA; Pig; IGF1R; SEM; WT
• ISSN: 2352-3204; 2352-3204
• DOI: 10.1016/j.reth.2024.08.025

To overcome organ shortage during transplantation, interspecies organ generation via blastocyst complementation has been proposed, although not yet in evolutionarily distant species. To establish high levels of chimerism, low chimerism is required early in development, followed by high chimerism, to effectively complement the organ niche. Very few human cells are expected to contribute to chimerism in heterologous animals. Previous studies had demonstrated increased donor chimerism in both intra- and interspecies chimeras in rodents, using insulin-like growth factor 1 receptor (Igf1r) knockout (KO) mice; deletion of the Igf1r gene in the mouse host embryo created a cell-competitive niche. The current study aimed to generate IGF1R–KO pigs and evaluate whether they have the same phenotype as Igf1r-KO mice. To generate IGF1R–KO pigs, genome-editing molecules were injected into the cytoplasm of pig zygotes. The fetuses were evaluated at 104 days of gestation. IGF1R–KO pigs were generated successfully. Their phenotypes were almost identical to those of Igf1r-KO mice, including small lungs and enlarged endodermal organs in fetuses, and they were highly reproducible. Pigs may allow the generation of organs using blastocyst complementation with developmentally-compatible xenogeneic pluripotent stem cells over a large evolutionary distance. •Insulin-like growth factor 1 receptor (IGF1R)-knockout (KO) pigs were generated and phenotypically compared to Igf1r-KO mice.•Phenotypes were similar with small lungs and enlarged endodermal organs that were reliably reproduced.•IGF1R–KO pigs can be used to generate organs by blastocyst complementation.•Developmentally-compatible, xenogeneic pluripotent stem cells can contribute donor cells to host tissues.