Researchers from Brown University and Yale University report that a small molecule compound has shown significant success in controlling the infectivity and spread of three polyomaviruses in human cell cultures. To date there has been no medication approved to treat such viruses, which prey on transplant recipients, people with HIV, and others whose immune systems have been weakened.
The compound, known by the abbreviated name “Retro-2,” was able to protect the vast majority of cells in cultures when it was administered even after infection began. According to results published in the journal mBio, 12 days of treatment with Retro-2 kept 90.5% of cells free from JC polyomavirus, 89% of cells clear of the BK polyomavirus, and 84% of cells protected from the SV40 polyomavirus. Infection rates and virus production were much higher among cells in cultures that were similarly infected, but left untreated as controls.
Christian Nelson, a Brown researcher, first thought to study Retro-2 after reading a 2010 paper showing that it blocks certain toxins, including ricin, from working through the endoplasmic reticulum (ER). Ricin and polyomaviruses have been thought to operate similarly.
Retro-2 appears to work by blocking the ability of polyomaviruses to sneak around host cells by hijacking the workings of the intracellular protein transportation hub—the ER. The researchers tested it in several ways, including with both kidney cells and brain cells, because those are the tissues in the body where polyomaviruses can cause disease. Retro-2 appeared effective in protecting the various cells, as long as it was present within several hours of infection. Read the article.
