Scientists have developed a potential new therapy based on immune molecules from cows to help people with hormone deficiencies.
The study shows that human hormones and antibodies can be fused together - mimicking long, stalk-like cow antibodies.
"We were inspired by this unique structure found in nature, and we assembled an antibody that might one day benefit humans," said co-first author Tao Liu, research associate at The Scripps Research Institute (TSRI) in the US.
The new study could provide the foundation for treatments for a range of other diseases.
For example, many people need injections of human growth hormone (hGH) to combat conditions such as Turner syndrome (which causes short stature in females), low birth weight and other hormone deficiencies. Unfortunately, the body degrades hGH quickly, sometimes within 30 minutes.
"This means people need to inject themselves every day," Liu explained.
Antibodies, however, can last for weeks in the body.
The bovine antibody has an unusual structure - a round base with a long amino-acid "stalk" pointing out. On the top of the stalk is a "knob region" that presumably binds to pathogens.
The researchers fused hGH to a coiled version of the bovine antibody's stalks. This fusion was stable and maintained the function of hGH.
"It acts just like the normal growth hormone," Liu noted.
"This means the treatment might only need to be injected once a week or even once a month in humans. It would be so much easier for patients," he added.
The study was published in the journal Proceedings of the National Academy of Sciences.
