ABSTRACT
Type 1 Interferons (T1 IFN) play a pivotal role in innate immune responses against viral infection. Recently, this anti-viral cytokines are shown to be induced during bacterial infections via activation of various pattern recognition receptors (PRRs) including Toll-like receptors, RIG-I-like receptors, or NOD-like receptors. Signaling mediators such as MyD88, TRIF, MAVS, STING, or RIP2 of the receptor signaling pathways are also involved in T1 IFN responses depending on the bacterial species and their ligands. However, role of T1 IFN in anti-bacterial immunity is still obscure and its effect on immunological pathogenesis during bacterial infection has been controversial. It has been reported that T1 IFN could provide protective effect on several bacterial infections but it also aggravates pathogenic situation during some intracellular pathogens or secondary bacterial infection after respiratory viral infection. Here, we summarize recent findings how T1 IFN is induced by various bacterial pathogens and discuss the potential effect of T1 IFN responses on immune responses against bacterial infection.