Llamas are bored, slow-eating South American camelids prized for their fur and leather, but beneath the fur and hide, these domesticated beasts of burden hide something else. Powerful tools Something that humans are trying to use.
Scientists have discovered that when llamas (Llama glama) are exposed to certain deadly human viruses, their bodies produce powerful immune proteins that are different from those produced by humans.
Using this knowledge, researchers at the National Institutes of Health (NIH) have developed a human-llama hybrid antibody that can suppress HIV, one of the most insidious infectious diseases known to man.
The Human Immunodeficiency Virus (HIV) is a cunning, shape-shifting virus that rapidly evolves to block human antibodies. Cling and restrain Foreign threats.
“Traditional antibodies are bulky, making it difficult for them to find and attack the surface of the virus.” explain Jianliang Xu, a biologist at NIH and George State University;
Llamas have different antibodies. As with sharks, alpacas and camels, Llama It is one of the few animals known to produce ultra-small antibodies called nanobodies, which are about one-tenth the size of a normal antibody.
These nanobodies are “agile” and flexible – their small size and elongated shape allow them to slip between the virus’s defenses and suffocate the most infectious parts of the virus.
Stimulates the production of HIV-sTo develop the specialized nanobodies, NIH researchers injected parts of the HIV-1 envelope into one llama 13 times within a year.
Then, through careful design, they took the most potent HIV nanobody they could find and fused it with part of a broad-spectrum human antibody against HIV.
These broadly neutralizing antibodies (bNAbs that can target multiple strains of HIV Discovered in some human patients in the 1990s. but After nearly 40 years of research, scientists have yet to develop an HIV vaccine or long-acting bNAbs-based treatments that can effectively resist viral mutations.
Although the human antibodies and llama nanobodies target different parts of the virus, each alone can neutralize 90 percent of HIV-1 strains. Combining the two approaches is “super-potent,” the researchers write. The llama-human chimera was able to suppress 96 percent of 208 HIV strains in the lab.
This is 10 times more potent than a human-llama antibody previously developed by the same researchers.
“These nanobodies are the best, most potent neutralizing antibodies to date, and I think they hold great promise for the future of HIV treatment and antibody research,” says Peyton Chang, a biology doctoral candidate at Georgia State University.
“We hope that one day these nanobodies will be approved as treatments for HIV.”
It remains to be seen whether the newly developed llama-human chimera will be able to target HIV infection in live animals and humans, but the fact that the treatment can bind to two of the virus’s most vulnerable sites should make it harder for pathogens to escape the immune system’s clutches.
Antibody infusions have recently emerged as a promising way to treat, prevent or even cure HIV, but previous studies have found that they require high doses of very specific bnAbs to have a lasting effect.
Perhaps llama nanobodies are a way to make these treatments more potent at lower concentrations, but how long the drugs last is another challenge.
HIV antibody treatments that only need to be administered to patients about once a year could prove highly effective in clinical practice – currently, these treatments require booster doses every few months.
NIH researchers are now working to engineer new combinations of llama and human antibodies to see if they can develop even more powerful treatments.
This study Cutting-edge science.
