A rapidly growing field of disease treatments now revolves around the use of antibodies. These immune system foot soldiers identify and neutralize foreign objects like bacteria and viruses, but producing them en mass for modern pharmacology is no simple task. That's why a team from Sanford Applied Biosciences in the US has recruited a small bovine army to help.
To make snake anti-venom, we inject a tiny amount of the deadly substance into a horse and let its equine immune system makes antibodies, which we then harvest and process into serum. The Sanford team is applying the same concept but with a high-tech twist — they've genetically modified the cows to produce human antibodies that don't require processing by replacing the bovine immune system with a human one.
"We have cows that produce human antibodies — they're human beings with respect to their immune system," Dr. David Pearce, the COO and VP of Sanford Research, explained to Fast Co. These cows were specifically designed by "transferring a Human Artificial Chromosome (HAC) vector carrying the entire human IgH and IgL loci into bovine cells where bovine Ig genes are knocked out by the sequential gene targeting, followed by chromatin transfer," according to the Sanford website.
Dubbed the siversitAb system, this process produces large quantities of fully human IgG antibodies that can be purified from the other blood components and used in proof-of-concept (POC) testing. Compared to the middling amounts of antibodies we've been able to extract from mice, rats, and rabbits, the bovine method is a gold mine for medical research. As such, these man-made cows are treated like golden idols.
"They have to be kept in specific conditions. They have a human immune system, not a cow immune system, so they may be somewhat susceptible to bovine afflictions," Pearce told Fast Co. "We have a lot of regulations in terms of upkeep."