Post 65 is a link to an article about the creation of IL-6 mice to study immune responses to infections.
Regeneron specializes in genetically modified humanized mice that they create in mouse embryos with human DNA. Do you have proof that the DNA sources come from fetal tissues as opposed to the much cheaper and easier to come by adult donation or umbilical cord donation?
From the study:
“Fetal liver samples were obtained from the Human Fetal Tissue Repository at Albert Einstein College of Medicine, Bronx, NY, and from Advanced Biosciences Resources, Alameda, CA.”
https://www.sciencedirect.com/science/article/pii/S0006497120336673#ceack10