Latent viruses and their damaging effects and possible cures are an intense focus of current research efforts. I not aware of any cure for these elusive latent viruses, who are virtually undetectable by the immune system during latent stages. Examples of latent viruses include herpes, Epstein Bar, and Cytomegalovirus. Latent viruses are suspected, and occasionally proven, to be casual or contributing factors to mental/developmental disorders, such as autism and schizophrenia and to physical disorders like high blood pressure and atherosclerosis (see the first link).
Antiviral suppression therapy is the best treatment currently available. In today’s review, researchers* may have taken a important step toward the development of a potential cure for latent viruses. Links to Wikipedia are provided for several uncommon (at least in psychology) terms and medications.
In the current study, researchers hypothesized that cells infected with latent viruses would express their normally intracellular phosphatidylserine or “phospholipids” on the outer cell surface (“turn inside out”); thus, providing a potential target for therapy. Guinea pigs were infected with the deadly (to these animals) Pichinde virus, whose effects are very similar to Lassa fever in humans, and consistent with predictions, phospholipids emerged on cell surfaces within 6 hours. The guinea pigs were then given specific chimeric antibodies, called Bavituximab, during advanced, lethal stages of the Pichinde viral infection.
The results were amazing. Bavituximab not only bound to cells infected with the Pichinde virus, but also to their infectious virions. 50% of these animals recovered while 100% of the control group died. By day 135, no traces of the Pichinde virus were found in the animals. The researchers acknowledged this to be the first known successful treatment of advanced Pichinde viral infection. Combined therapy of Bavituximab plus the antiviral drug Ribavirin lead to a 63% treatment success rate. Moreover, cells infected with inﬂuenza A, vaccinia, vesicular stomatitis virus (VSV), and mouse cytomegalovirus (mCMV) viruses also responded to the Bavituximab binding. Similar results were achieved in mice who been given lethal levels of mCMC and then Bavituximab.
In terms of side effects, researchers stated that, “Bavituximab therapy seems to be well tolerated. Treated animals retained normal body weight, appetite, appearance and physical activity (data not shown). No evidence of toxicity was visible histologically (data not shown). Coagulation parameters remained within the normal range” (pg. 1359).
Pretty amazing stuff. Scientists are slowly but surely learning how to root out these devious viruses, at least in animals. I hope that similar type of treatments can used with in human subjects with major public health viral-based diseases, such as HIV/AIDS and herpes. Latent viruses may play a much larger role in physical and emotional health than we currently understand, and my hope is that these new research findings will translate into real world anti-viral treatments, possibly cures, for humans. This study certainly puts us one step closer to this goal.
7/11/09 Update: An interview with Dr. Thorpe, lead researcher of this study, can be found here.
*Soares, M., King, S., & Thorpe, P. (2008). Targeting inside-out phosphatidylserine as a therapeutic strategy for viral diseases. Nature Medicine, 14(12), December, 1357-1362.