Conservative pattern of interaction of bat and human IgG antibodies with FcRn

Recently, numerous studies report bats as reservoirs of emerging pathogens with little to no signs of infections. This is thought to be connected to the unique immune system of bats, which remains poorly characterized. Despite the physiological importance of the Neonatal Fc receptor (FcRn) in the homeostasis of IgG antibodies, it is unclear how its functional activity is evolutionary conservative among mammals, and so is the case for bats. Using surface plasmon resonance-based technology, we tested the interactions of IgG antibodies isolated from three bat species with recombinant human and mouse FcRn. Our data show that IgG from the studied bat species binds to both human and mouse FcRn, albeit with distinct affinities. Importantly, the binding pattern of bat IgG is similar to human IgG. This confirms the conservative nature of IgG-FcRn interaction and highlights the importance of FcRn IgG salvaging system in bats.

Automated summary

Recently, studies have found that bats can harbor emerging pathogens without showing signs of infection, possibly due to their unique immune system. This study used surface plasmon resonance technology to investigate the interaction of IgG antibodies from three bat species with human and mouse FcRn. The results showed that bat IgG can bind to both human and mouse FcRn, with different affinities. This confirms the conservation of IgG-FcRn interaction and highlights the importance of the FcRn IgG salvaging system in bats.