Immunodeficient pigs – a model for studying cell therapy
One of the main problems that complicate and slow down the process of evaluating the effectiveness of stem cell therapy is the high probability of transplant rejection. To solve this problem, researchers at the University of Missouri proposed using genetically modified pigs created by them, whose body does not reject human stem cells.
According to one of the leaders of the study, Professor Randall Prather, pigs are a very good model for studying and evaluating the effectiveness of therapy for human diseases, since their physiology is very similar to human physiology.
To create immunodeficient pigs, the authors used the TALEN system (transcription activator-like effector nucleases, similar to transcription activators effector nucleases) to specifically modify both alleles of the RAG-2 gene (recombination activation gene-2) in the DNA of pig somatic cells. After that, using the somatic cell DNA transfer method, they created animals with a mutation in both copies of this gene. At birth, the thymus in such pigs was absent or underdeveloped, and there were no T- and B-lymphocytes in the spleen. When kept under normal conditions, the animals showed a weakened phenotype, and by the age of 4 weeks, pronounced inflammatory and apoptotic changes developed in their spleen.
When kept in sterile conditions, immunodeficient pigs remained viable, and when they were injected with human induced pluripotent stem cells (iPSCs), mature teratomas – tumors consisting of cells of all three embryonic sprouts - rapidly formed. The animals also tolerated the introduction of pig trophoblast stem cells well.
Researchers believe that immunodeficient pigs will be widely used in biomedical research on transplantation and cell therapy.
Article by Kiho Lee et al. The involvement of human iPS cells and allogeneic porcine cells into pigs with inactivated RAG2 and accompanying severe combined immunodeficiency is published in the journal Proceedings of the National Academy of Sciences.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the University of Missouri:
MU Scientists Successfully Transplant, Grow Stem Cells in Pigs.
06.06.2014