New Class of Proteins Found in Corals Blocks HIV from Fusing with T-Cells

Researchers have found a new class of proteins in corals. These proteins called cnidarins can stop HIV virus from entering the T-cells. The research could enable scientists create new products that can lower HIV exposure risk in women.

There is an urgent need for anti-HIV microbicides that can reduce women's exposure to the virus. Women often have to rely on their partners to adopt safe sex methods. A product containing cnidarins could help women avoid HIV exposure risk by blocking the virus.

Also, the proteins stop the virus from entering the immune cells called T-cells, but not fight the virus. According to Koreen Ramessar, Ph.D., a postdoctoral research fellow at the National Cancer Institute, this property of cnidarins will prevent the virus from building-up resistance.

The proteins were found in feathery corals collected from Australia's northern coast. The study team used biorepository maintained by the National Cancer Institute to screen thousands of proteins before zeroing-in on cnidarins.

"It's always thrilling when you find a brand-new protein that nobody else has ever seen before," said senior investigator Barry O'Keefe, Ph.D., deputy chief of the Molecular Targets Laboratory at the National Cancer Institute's Center for Cancer Research. "And the fact that this protein appears to block HIV infection-and to do it in a completely new way-makes this truly exciting."

The team found and purified the cnidarin proteins. They even tested the efficacy of the protein in blocking HIV strains.

Cnidarins work by attaching themselves to the virus, which prevents HIV from penetrating the T-cell membrane. The mechanism by which the new class of proteins block HIV virus is unique, according to Ramessar.

In the next part of the study, researchers will be trying to generate the proteins in a large amount. Then they will conduct clinical studies to see whether or not the proteins have side-effects.

"When developing new drugs, we're always concerned about the possibility of undermining existing successful treatments by encouraging drug resistance in the virus," said O'Keefe in a news release. "But even if the virus became resistant to these proteins, it would likely still be sensitive to all of the therapeutic options that are currently available."

The research findings were presented at Experimental Biology 2014 meeting on Tuesday, April 29. National Cancer Institute funded the study.