That does not answer my question. I want to know what method Regeneron used for their humanized mice used in their antibody treatment.
This how they did it in 2017:
“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. Tissues were cut in small fragments, treated for 45 minutes at 37°C with Collagenase D (100 ng/mL; Roche) and a cell suspension was prepared. Human CD34+ cells were purified by density gradient centrifugation, followed by positive immunomagnetic selection using anti-human CD34+ microbeads (Miltenyi Biotec). Newborn pups were sublethally irradiated with 180 cGy and 100 000 CD34+ cells were injected into the liver. The mice were bled 8 to 10 weeks post-engraftment to check for the reconstitution of the human immune system. More than 20 fetal liver samples were used and the same donor sample was transplanted for both human IL-6–positive and negative recipients to exclude variations that related to the donor.”
In the acknowledgments it reads “The authors thank the Regeneron Pharmaceuticals’ Velocigene team for generating human IL-6 knock-in mice”
https://www.sciencedirect.com/science/article/pii/S0006497120336673#ceack10
I want to know if this how they humanized their mice for regen-cov2.
https://www.regeneron.com/science/technology link to their several videos of their tech.
VI mice are created by injecting mice embryos with genetically modified human DNA via BACvec Bacterial Artificial Chromosomes vectors.
I am going to assume their DNA is adult or cord sourced because it is cheap and plentiful. I am assuming that since they wanted to produce human covid antibodies it was gotten from recovered sick people.
Again, Regeneron plainly states that no fetal tissue was used in development or production and HEK was used only in efficacy testing. And HEK was sourced from a therapeutic abortion when it was the only legal kind allowed. So you will have to decide where your moral line is drawn.
well, you posted the procedure to harvest CD cells but if you want to know where the humanized mice come from? They come from mice farms :)
https://www.creative-biolabs.com/drug-discovery/therapeutics/humanized-immune-checkpoint-mice.htm