Type III IFN receptor expression and functional characterisation in the pteropid bat, Pteropus alecto

Area of Science:

• Virology
• Immunology
• Genetics

Background:

• Bats are natural reservoirs for numerous viruses, posing spillover risks to other mammals.
• Their asymptomatic viral infections suggest efficient innate immune control, particularly via interferons (IFNs).
• Type I and III IFNs are crucial in mammalian antiviral defense, and both are found in pteropid bats.

Purpose of the Study:

• To characterize the type III interferon receptor (IFNλR) complex in the black flying fox (Pteropus alecto).
• To investigate the tissue distribution and cellular responsiveness of the bat IFNλR system.
• To confirm the functional role of the bat IFNλR1 chain in mediating IFN-λ signaling.

Main Methods:

• Gene characterization of IFNλR1 and IL10R2, the components of the type III IFN receptor complex.
• Analysis of tissue distribution of the bat IFNλR complex.
• In vitro assessment of epithelial and immune cell responsiveness to IFN-λ treatment.

Main Results:

• The bat type III IFN receptor complex (IFNλR1/IL10R2) was characterized in Pteropus alecto.
• The IFNλR complex exhibits wide tissue distribution.
• Both epithelial and immune cells in bats are responsive to IFN-λ, with IFNλR1 confirmed as a functional receptor chain.

Conclusions:

• This study provides the first description of an interferon receptor in any bat species.
• The responsiveness of bat cells to IFN-λ highlights the importance of the type III IFN system in bats' innate antiviral immunity.
• The findings support a significant role for type III IFNs in controlling viral infections within bats.