Scientists hope that an HIV inhibitor they grew in tobacco could be used in a gel to prevent HIV transmission during sex, particularly among women in the third world, the Courier-Journal reports.

According to the article, a scientist from Louisville's James Graham Brown Cancer Center has used Kentucky tobacco plants to inexpensively grow a protein-based HIV inhibitor, called Giffithsin, that can possibly prevent the transmission of the virus during sexual activity.

Scientists have known about Giffithsin's HIV-blocking ability for some time, but they lacked a cheap way of producing large amounts of the protein. No prophylactic gel has made it past the testing phase and onto the general market. But unlike most previous gels, which directly attack the HIV virus, one made with Giffithsin would block transmission.

If the success rate of the clinical trials is high, the preventive gel could become an affordable method of reducing new HIV infections in places such as sub-Saharan Africa, where condom use is inconsistent.

Sub-Saharan Africa accounted for three quarters of AIDS deaths in 2007 and two thirds of all people living with HIV.