In what can only be described as an ironic twist of nature, the tobacco plant may have a chance to repair it’s bad reputation by helping in the production of a potent inhibitor of the Human Immunodeficiency Virus, or HIV, the virus that causes AIDS.

The compound in question is called griffithsin, and laboratory experiments have shown that it is highly effective in preventing HIV infection in laboratory animals and in human cells in vitro. Studies are being planned to test its efficacy in humans.

However, until now, the cost of producing griffithsin has always been prohibitively expensive because the only known source in nature has been the red algae found in New Zealand, which produce too little to be economically worthwhile. Attempts at employing recombinant DNA technology to produce it have also proven to be too tedious and expensive to warrant the large scale production that would be necessary to have any significant benefit.

Now, however, there is a novel method to produce large scale amounts by employing a genetically modified virus that infects tobaccos plants. The virus in question is the tobacco mosaic virus, or TMV.

The way it works is like this: scientists take the DNA for griffithsin and literally splice it into the DNA of the TMV, creating a viral “vector” for the gene. Certain viruses, including TMV and HIV, replicate by infecting a target cell and then commandeering the host cell machinery to make more of itself, thus converting the cell into virtual virus factories. Since the griffithsin DNA is now incorporated the virus genome, as more of the virus is produced, so too is the griffithsin. The genetically modified TMV is then infected into a close living relative of the commercial tobacco plant by simply spraying the virus onto the plant. The leaves are then harvested, after which the microbicide can be extracted in large quantities.

Griffithsin has been slated for use as a vaginal cream which would be applied before sexual intercourse in the hopes of preventing heterosexual transmission of HIV. The authors hinted that it was not unthinkable to create a griffithsin cigarette, but one can’t help but wonder what sort of outcry that would elicit.

Even still, it is interesting when you consider that for all the negative press that tobacco has received in the past several years, it just might have its second act as a public health hero.