Duke-NUS study uncovers why bats excel as viral reservoirs without getting sick

October 26, 2020

SINGAPORE, 27 October 2020 - Bats act as reservoirs of numerous zoonotic viruses, including SARS-CoV, MERS CoV, Ebola virus, and--most likely--SARS-CoV-2, the pathogen behind the ongoing coronavirus pandemic. However, the molecular mechanisms bats deploy to tolerate pathogenic viruses has remained unclear.

Now scientists from Duke-NUS Medical School, Singapore, have discovered novel molecular mechanisms that allow bats to tolerate zoonotic viruses without getting sick. Published this week in the Proceedings of the National Academy of Sciences (PNAS), the study suggests that bats adopt unique strategies to prevent overactive immune responses, which protects them against diseases caused by zoonotic viruses.

The team examined three bat species--Pteropus alecto (black fruit bat), Eonycteris spelaea (cave nectar bat), and Myotis davidii (David's myotis bat)--and identified mechanisms that balance the activity of key proteins that play a major role in mediating immunity and inflammatory responses in mammals. These mechanisms enable bats to harbour and transmit zoonotic pathogens without setting off the detrimental consequences of immune activation.

One of the mechanisms bats use is to reduce the levels of caspase-1, a protein that triggers a key inflammatory cytokine protein, interleukin-1 beta (IL-1β). Another mechanism they employ hampers the maturation of IL-1β cytokines through a finely-tuned balancing between caspase-1 and IL-1β.

"Suppression of overactive inflammatory responses improves longevity and prevents age-related decline in humans. Our findings may offer potential insights to the development of new therapeutic strategies that can control and treat human infectious diseases," said Professor Wang Linfa, senior and corresponding author of the study from Duke-NUS' Emerging Infectious Diseases (EID) Programme.

"This study exemplifies the world-class research led by our talented faculty to advance fundamental scientific knowledge. Professor Wang's research is all the more important in the context of COVID-19, by contributing to a greater understanding of how zoonotic diseases persist in nature, and potentially aiding new approaches to managing future outbreaks," said Professor Patrick Casey, Senior Vice-Dean for Research, Duke-NUS Medical School.
-end-


Duke-NUS Medical School

Related Bats Articles from Brightsurf:

These masked singers are bats
Bats wear face masks, too. Bat researchers got lucky, observing wrinkle-faced bats in a lek, and copulating, for the first time.

Why do bats fly into walls?
Bats sometimes collide with large walls even though they detect these walls with their sonar system.

Vampire bats social distance when they get sick
A new paper in Behavioral Ecology finds that wild vampire bats that are sick spend less time near others from their community, which slows how quickly a disease will spread.

Why doesn't Ebola cause disease in bats, as it does in people?
A new study by researchers from The University of Texas Medical Branch at Galveston uncovered new information on why the Ebola virus can live within bats without causing them harm, while the same virus wreaks deadly havoc to people.

The genetic basis of bats' superpowers revealed
First six reference-quality bat genomes released and analysed

Bats offer clues to treating COVID-19
Bats carry many viruses, including COVID-19, without becoming ill. Biologists at the University of Rochester are studying the immune system of bats to find potential ways to ''mimic'' that system in humans.

A new social role for echolocation in bats that hunt together
To find prey in the dark, bats use echolocation. Some species, like Molossus molossus, may also search within hearing distance of their echolocating group members, sharing information about where food patches are located.

Coronaviruses and bats have been evolving together for millions of years
Scientists compared the different kinds of coronaviruses living in 36 bat species from the western Indian Ocean and nearby areas of Africa.

Bats depend on conspecifics when hunting above farmland
Common noctules -- one of the largest bat species native to Germany -- are searching for their fellows during their hunt for insects above farmland.

Tiny insects become 'visible' to bats when they swarm
Small insects that would normally be undetectable to bats using echolocation suddenly become detectable when they occur in large swarms.

Read More: Bats News and Bats Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.