Researchers at the International AIDS Vaccine Initiative at Scripps Research Institute have discovered that cows can produce antibodies that effectively neutralize HIV. Thus far, developing an effective vaccine for HIV has been hampered by the ability of the virus to mutate. Some people who have been infected with the virus for a period of years develop antibodies that are able to attack parts of the virus that do not mutate. Cows exposed to HIV, on the other hand, begin developing these antibodies within weeks of exposure to the virus. In fact, a long term study of one of the cows showed the animal could neutralize 20% of HIV strains within 42 days and 96% of tested strains within 381 days. The team isolated an antibody from this cow and found it was effective at neutralizing 72% of strains. The findings were published in the journal Nature.
As ruminants, the ability for cattle to produce such potent antibodies likely arose from their ability to prevent infections from the large diversity of microbes that call their digestive tracts 'home'. The hope is to develop vaccines, microbicides or other therapeutics to prevent infection as well as to understand how we might be able to coax the immune system of humans to fight off the virus.
Sok D, Le KM, Vadnais M, Saye-Francisco K, Jardine JG, Torres J, Berndsen ZT, Kong L, Stanfield R, Ruiz J, Ramos A, Liang C-H, Chen PL, Criscitiello MF, Mwangi W, Wilson IA, Ward AB, Smider VV, Burton DR. Rapid elicitation of broadly neutralizing antibodies to HIV by immunization in cows. Nature. Published online 20 July 2017. doi:10.1038/nature23301