Scientists continue to search for antibodies that effectively neutralize HIV. One team has reported a potential breakthrough. Here a team led by investigators at the Scripps Research Institute in Jupiter, Florida, has found that building a molecule from scratch—based on an intimate knowledge of HIV pathology—can block infection. This antibody is “synthetic” rather than naturally occurring. Synthetic antibodies are chemicals that can be tuned to recognize specific molecules.
The synthetic antibody is called eCD4-Ig. The antibody mimics both CD4 and CCR5, the two T-cell surface receptors bound by HIV, binding the virus and flagging it for destruction.
The eCD4-Ig construct effectively blocked infection in vitro—better than all known HIV antibodies—and transfecting a gene for the synthetic molecule into four monkeys protected the animals from simian HIV despite being dosed with successively higher doses of the virus for nearly eight months.
“It is absolutely 100-percent effective,” lead author Michael Farzan, a viral immunologist at Scripps, told The Wall Street Journal, adding “there is no question that it is by far the broadest entry inhibitor out there.”
“I am a huge fan of this paper,” Oregon Health & Science University’s Nancy Haigwood, who wrote an accompanying Nature editorial, told the website Science. “It’s really very creative and a breakthrough as far as I am concerned.”
The findings have been published in the science journal Nature. The study is titled “AAV-expressed eCD4-Ig provides durable protection from multiple SHIV challenges.”
