Certain Components in Frogs' Skin Mucus Could Kill Flu Virus

A team of researchers from the Emory Vaccine Center and the Rajiv Gandhi Center for Biotechnology in India found that certain components in frogs' skin mucus have the ability to kill the H1 variety of the dreaded influenza virus.

Their discovery, described in a paper published in the journal Immunity, showed that the skin of the frogs are capable of secreting a so-called "host defense peptides" that defend them against bacteria.

"Anti-flu peptides could become handy when vaccines are unavailable, in the case of a new pandemic strain, or when circulating strains become resistant to current drugs," said Joshy Jacob, PhD, associate professor of microbiology and immunology at Emory Vaccine Center and Emory University School of Medicine and senior author of study, in a press release.

For the study, the researchers used mild electrical simulation to collect skin secretions from the Indian frog Hydrophylax bahuvistara. The researchers found various antiviral peptides in the skin secretion. One of the peptides they found were named urumin, after a whip-like sword called "urumi" used in southern India centuries ago.

In mouse models, the researchers observed that urumin was able to protect unvaccinated mice against specific H1 strains of the flu virus. As opposed to common antiviral peptides that work by punching a hole in the cell membranes, urumin appears to bind the stalk of hemagglutinin. The stalk of hemagglutinin is a lesser known variable region of the flu virus and is also the proposed target of universal flu vaccines.

Despite it being effective against H1 strains of the flu virus, urumin was not effective against other current strains of the virus, such as H3N2. Due to this, the researchers are searching for other frog-derived peptides that can kill other stains of the flu virus and can also protect humans from other viruses, such as Zika and dengue.

The researchers are also looking for an effective way to stabilize antiviral peptides, making them tough enough to prevent being broken down by some enzymes in the body. By doing so, the researchers could easily develop antimicrobial peptides into effective drugs.