STING1 and listeriosis: We conclude that induction of type I IFN during Listeria infection of STING pathway deficient cells is dependent on RIG-I, while the RIG-I pathway is redundant in immune cells such as monocytes, as they possess a STING-dependent pathway and are therefore able to sense c-di-AMP and bacDNA in the cytosol in a pol III/RIG-I independent manner.