Innate Immunity in Bats
Christopher F. Basler
from: Bats and Viruses: Current Research and Future Trends (Edited by: Eugenia Corrales-Aguilar and Martin Schwemmle). Caister Academic Press, U.K. (2020) Pages: 119-134.
Bats are reservoir hosts for several viruses that cause severe disease in humans, raising the question as to whether bats have unique innate antiviral immune responses. There are three classes of interferons (IFN) type I, II and III, with type I and type III IFNs serving as a rapid innate antiviral response that up-regulates interferon stimulated genes, to control virus replication. Activation of type I and type III IFN expression is mediated by pattern recognition receptors, which detect products of virus replication and initiate downstream signaling. Genome sequencing and transcriptional profiling studies indicate that the major components of the type I, II and III IFN systems are intact in bats. There is evidence for constitutive IFN-α expression in at least some bats and a corresponding higher baseline expression of some interferon stimulated genes (ISGs), which perhaps influences how bats tolerate infection. Furthermore, viruses that use bats as reservoir hosts have evolved mechanisms to suppress bat IFN responses. There is also emerging evidence for altered inflammation in bats. Future functional studies should further clarify how the bat innate immune system and viruses interact read more ...