Recently published research in PLoS ONE reported a breakthrough in the development of broad-spectrum antiviral therapy, theoretically capable of working against all types of viruses, from naturally emerging viruses such as influenza and SARS to clinical viruses like hepatitis and HIV.
Viruses are very small acellular organisms that, when introduced into another organism, invade and commandeer cells in order to replicate and spread themselves. When viruses attempt to replicate themselves, the host organism usually has an immune system response which disrupts the replication process. Yet many viruses such as HIV can outsmart the immune system, leading to continued viral replication that can cause serious damage to the organism.
There are both preventative and therapeutic treatment options available to deal with viruses, but they have several limitations. For instance, vaccines can be used to build up strong immune system responses to specific viruses, which ensure that if the organism does become exposed to the virus, it is able to fight the virus off. However, vaccines usually need to be administered prior to (or in some cases shortly after) exposure of the virus, which is not always possible. In addition, when dealing with emerging infectious diseases such as SARS (which was unpredictable and quickly spread between people in Toronto), there is often little time to develop and administer vaccines to the public.
Therapeutic treatment options also exist, which can be used to treat viral infections post-exposure. The success of this type of treatment can be seen in how it has helped prolong the life of people who have contracted HIV. Nevertheless, this class of treatment is also subject to the same limitations as vaccines and can moreover become ineffective if the virus mutates and becomes resistant to the drug.
In response to these treatment limitations, Dr. Todd Rider and his colleagues from the Massachusetts Institute of Technology developed a new antiviral drug called Double-Stranded RNA Activated Caspase Oligerizer (DRACO), which targets cells that have been infected by a virus. When viruses attempt to replicate themselves in cells, they often create long strings of double-stranded RNA that are not found in regular human or animal cells. This approach works by specifically targeting the cells that have these long strings of double-stranded RNA and causes them to undergo apoptosis (programmed cell suicide) while ignoring all the other healthy cells.
In his research, Dr. Rider tested the new drug on 15 different viruses (including the common cold, H1N1 influenza, and polio virus) and it was effective against them all. Although his earlier research was primarily conducted on mammalian cells cultured in a lab (which leaves open the possibility that the drug might not work on living animals), his most recent work has focused on the effect of the drug on mice infected with influenza and has led to some promising results.
As a broad-spectrum antiviral drug, the development of DRACO has tremendous potential to impact the treatment of viral diseases. More research and time will tell whether this drug ends up being safe and effective for the treatment of viral infections in humans.
