April 13, 2009

Fly Spit may Ward off Blinding Eye Diseases

The saliva from a fly may be able to save someone's eyesight.

Researchers from the National Institute of Allergy and Infectious Diseases have found what they call a "magic potion" of proteins in the saliva of the black fly that help it spread parasites that cause onchocerciasis or river blindness "“  a devastating eye-disease. They say a better understanding of these proteins may lead to better drugs and a vaccine for river blindness and other diseases spread by biting insects.

Scientists collected salivary glands from hundreds of adult female black flies. They isolated the proteins using high-tech analytical gear. Researchers identified 72 different proteins, including several that are new to science. They say these proteins could help lead to the development of new drugs or vaccines against diseases transmitted by the black fly and other blood-sucking insects, including mosquitoes, midges and sand flies.

The new study shows the saliva of adult female black flies has substances in it that mute the human body's natural defenses. This cocktail of chemicals makes the body more vulnerable to disease when infected flies bite the skin, but until now, nobody had identified the specific chemicals involved.

River blindness affects more than 17 million people worldwide. It is most common in rural Africa.

SOURCE: Journal of Proteome Research, 2009;8:1474-1488