Glioma tumor cells (in red) and being destroyed in a rat brain by a chimeric virus (green) containing elements of the Lassa virus, an ebola-like pathogen. Image credit: Yale

Ebola is, perhaps, one of the most frightening modern diseases. The virus is characterized by flu like symptoms, excessive bleeding from bodily orifices, hemorrhaging, organ failure, and (ultimately) death. What's more, all of this can occur in a matter of days.

Fortunately, scientists have been making great progress in the fight against Ebola, and it seems that a working vaccine is just around the corner. But that's not all the good news that has recently come out in relation to hemorrhagic fever viruses.

Recently, scientists used genes from the Lassa virus (which is a virus that shares many characteristics with Ebola) and genes from VSV (a relative of rabies) to completely destroy brain cancer in test subjects. Best of all, this was done without causing any adverse reactions in the brain.

Of course, this is still early research. To date, the treatment has only been tried in mice, so there is no guarantee that it will work in humans or (if it does) that it will be safe.

Still, the effectiveness of this treatment is an amazing breakthrough, as brain tumors are among the most difficult for drugs to reach. The difficulty comes because of something known as the "blood-brain barrier." Ultimately, this barrier serves as a built-in defense system—it is a collection of cells that act as a kind of roadblock, stopping harmful toxins found in the blood stream from entering brain tissue. Unfortunately, it also stops medicine, making it very difficult to deliver drugs to the brain to treat things like cancer and Alzheimer's.

And not only did this treatment pass through the blood-brain barrier, according to research released April 16 in the Journal of Virology, it destroyed brain tumors in mice.

Tony van den Pol, professor of neurosurgery at the Yale School of Medicine and senior author of the study, notes that the treatment was surprisingly safe for healthy cells, asserting in the press release that “the chimeric virus turned out to be completely safe in animals and tended to specifically target cancer cells in the brain."

This amazing accomplishment was made possible by the chimeric nature of this treatment. "Chimeras" are organisms that have genetically distinct cells (they usually have a blending of genes, either from different species or from different sexes of one species). Ultimately, scientists used this "blending" to manufacture a treatment that may be able to beat brain cancer.

On its own, VSV is able to pass through the membranes that protect the brain and infect brain tumors; however, the unaltered virus causes serious neurological damage. The Yale team discovered that portions of VSV can be spliced with portions of other viruses to attack brain tumors without hurting healthy cells.

There were a number of viruses that were tested before a efficient treatment was found. For example, one version contained Ebola genes, and while they did reach the brain tumor, they were not effective when they attacked the tumor. The altered Lassa virus, however, safely and effectively targeted and destroyed cancer cells within the brain.

“We are very excited about these new chimeric viruses that contain genes from multiple viruses. They work well in targeting cancer in animals, and we hope that they will also work effectively if tested in humans,” said van den Pol.


Share This Article