Chikungunya biomarker offers hope for patients

Scientists claim to have found a specific biomarker for Chikungunya, which they say could serve as an early and accurate prognosis of patients at risk from the mosquito-borne infectious disease endemic to Southeast Asia and Africa.

There is no clinically-approved vaccine or treatment for chikungunya fever, which is characterised by persistent joint pains that linger for months. Most patients recover within a week but those with a weak immune system may also die from it.

Scientists at A*Star’s (Agency for Science, Technology and Research) Singapore Immunology Network (SIgN) discovered that patients who respond to the disease at the onset with high levels of IgG3 — a naturally-acquired antibody — are protected from the more severe form of chikungunya fever.

On the other hand, those with a delayed IgG3 response generally have less acute symptoms at the start, but are more susceptible to chronic debilitating joint pains later on, the www.channelnewsasia.com reported.

This led the researchers to identify IgG3 antibodies as a specific biomarker of patients who have increased risk of the severe form of chikungunya fever. The team also collaborated with experts from A*STAR’s Institute for Infocomm Research and uncovered a defined segment of the chikungunya viral protein, named “E2EP3”.The viral protein was able to induce protective response from IgG3 in pre-clinical models.
Mice vaccinated with the E2EP3 peptides were protected against the chikungunya virus with significant reduction in viral counts and joint inflammation.

The team said the finding raises hope for a new effective chikungunya vaccine that can offer protection against the chikungunya virus in the event of an outbreak.
“Long-term treatment required for the chronic joint pain in chikungunya-infected patients places social and economic burden for both patients and the public healthcare system,” said Dr Lisa Ng, who led the research.

“We are excited that the mechanistic insights gained through our collaborative research with the local hospitals and international research partners have led to discovery of ‘new weapons’ to tackle chikungunya more effectively.”