Transgenic rice crops may offer low-cost way to prevent HIV infection

July 30, 2018

According to a study published in the Proceedings of the National Academy of Sciences, a team of researchers from Spain, the United States, and the United Kingdom has successfully created a strain of genetically modified (GM) rice that will produce HIV-neutralizing proteins. Every year there are 1.8 million new HIV infections around the world, mainly in Africa. According to the World Health Organization, at the end of 2017, about 37 million people were living with HIV around the world.

A vaccine, however, still isn’t available for HIV, so oral medications and increasing public knowledge about how the disease spreads have been the best defense. Oral medications aren’t always available in developing countries, so more options are still needed.

The researchers tested different substances that are used in microbicidal creams to find the best combination against different strains of HIV, analyzing the specific activity of binding to antigens of each protein. The invitro tests validated the effectiveness of a “cocktail” of three proteins in the endosperm of the rice. The 2G12 monoclonal antibody, Griffithsin antiviral lectin (GRFT)—consisting of a red alga—and the cyanovirine-V (CVN) of a cyanobacteria, bind to a glucoprotein that forms part of the coating of HIV, gp120, necessary for the virus to invade human cells.

Once grown, the rice produces seeds that can be processed on-site to make a topical cream containing the proteins. The cream can then be applied to the skin to allow the proteins to enter the body. The GM rice produces one type of antibody and two kinds of proteins that bind directly to the HIV virus, preventing them from interacting with human cells. The researchers note that the cost of making the cream is nominal once the rice has been grown, and people living in infection areas can grow as much of the rice as they need, then make the paste and apply it themselves.

The researchers concluded that “cereal plants such as rice expressing multiple HIV-neutralizing proteins in GRAS-status seeds offer an inexpensive platform for the production of microbicidal mixtures with the added benefit that dry seeds can be stored indefinitely under ambient conditions.”