Insect Virus Kills Liver-Stage Malaria In Mice

Researchers in Japan have discovered that an insect virus can completely eliminate liver-stage malaria parasites in mice.

AsianScientist (Dec. 24, 2018) – In a study published in the Journal of Immunology, scientists in Japan have used a virus that typically infects insects to destroy the malaria parasite.

Malaria is caused by Plasmodium, a parasite spread by the Anopheles mosquito as it feasts on blood. The parasite is released into the bloodstream and travels to the liver to mature, before being released back into the bloodstream where it infects red blood cells.

In the case of Plasmodium vivax—the most widely distributed human malaria parasite in the world—the parasites can lay dormant in the liver and cause disease to recur months or even years later. The dormant-phase parasites are known as hypnozoites and currently can only be targeted by a single drug, primaquine. However, primaquine is associated with a high risk of life-threatening hemolytic anemia in people with glucose-6-phosphate-dehydrogenase enzyme deficiency.

To expand the range of available treatments for malaria, researchers from Kanazawa University, Japan, have demonstrated that that treating mice with baculovirus (BV) gets rid of liver-stage parasites. BV typically only invades insect cells and leave mammalian cells alone.

In a series of experiments, the researchers confirmed that intramuscular administration of BV not only provides complete protection against a subsequent sporozoite infection but also eliminates existing liver-stage parasites completely. The elimination of liver-stage parasites with BV was superior to primaquine treatment.

Further work is needed to confirm these findings in primates and humans, but initial results suggest that there are several potential benefits of BV as a new non-hemolytic single-dose alternative to primaquine.

“Currently, P. vivax patients must receive several doses of antimalarials for treatment. Adding BV to existing therapeutic regimes could reduce the risk of infection during treatment,” said corresponding author Professor Shigeto Yoshida of Kanazawa University. “[BV] could also provide protection against [malaria] in the liver. There are several challenges in the treatment of malaria, which we hope to overcome with our work.”

The article can be found at: Emran et al. (2018) Baculovirus-Induced Fast-Acting Innate Immunity Kills Liver-Stage Plasmodium.


Source: Kanazawa University; Photo: Shutterstock.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist