New hope for treatment of Ross River fever

Ross River virus (RRV) is a nasty customer with infection known to cause debilitating arthritis and pain in several joints simultaneously, a condition called polyarthritis. It’s also not the only virus to cause such symptoms, with others including chikungunya, Sindbis, mayaro and o'nyong-nyong.

New hope for treatment of these arthrogenic alphaviruses comes from a group of researchers at Griffith University’s Institute for Glycomics.

They have revealed a key link between a common cytokine – a protein signalling molecule – called macrophage migration inhibitory factor (MIF) and the arthritic symptoms caused by these viruses.

In a paper published in the Proceedings of the National Academy of Sciences of the U.S.A. they show that levels of MIF are upregulated in mice infected with RRV, which corresponded with severe joint inflammation.

MIF-deficient mice, on the other hand, developed mild symptoms.

“This research has shown that in cases where a virus has induced arthritis, the prevalence of MIF within the joints is increased,” said Professor Suresh Mahalingam, lead researcher on the study.

“MIF is responsible for causing the inflammation and tissue damage,” he said. “Our studies have shown that viral infections can trigger this protein which may explain why patients diagnosed with rheumatoid arthritis suffer from flare-ups when they have an infection.”

The finding opens the possibility of using drugs that target the receptors bound by MIF to reduce it’s inflammatory effects.

“MIF is known to bind to receptors which cause inflammation in the joints,” said Mahalingam . “New drugs can now be developed to target MIF in order to neutralise it and prevent it binding to a receptor. The best part is that blocking MIF does not compromise antiviral immunity.”

Such a drug might be effective not only against RRV and other arthrogenic alphaviruses but also viruses like Dengue Fever and pneumonia that cause tissue inflammation.

“Pharmaceutical companies are already targeting MIF but we are now seeking to engage with them about extending the application of those drugs with regards to viral induced inflammation.”