March 31, 2009

Modified tobacco plant may block HIV

A gel derived from a close relative to the tobacco plant is being tested as an affordable preventative measure for HIV, U.S. researchers said.

Kenneth Palmer, a senior scientist in the University of Louisville's Owensboro Cancer Research Program, has published research that suggests growing large quantities of the protein griffithsin found in the transgenic plant Nicotiana benthamiana can prevent human immunodeficiency virus from infecting cells of the immune system, the university's James Graham Brown Cancer Center said in a release.

Palmer said the drug could be manufactured in the form of a microbicide gel or film for topical application, with a selling price comparable to condoms.

They modified the tobacco mosaic virus to incorporate the griffithsin gene and infected more than 9,300 tobacco plants. Scientists were able to extract enough griffithsin to produce about 100,000 HIV microbicide doses from the leaves. The chemical performed identically to griffithsin produced by other methods, the report said.