STING1 and infection: Recently, c-di-AMP produced by live gram-positive bacteria, whether intracellular bacteria such as Staphylococcus aureus and Listeria monocytogenes or extracellular bacteria such as Streptococcus pyogenes, has been reported to induce a previously unappreciated cell-autonomous response by STING to elicit an augmented IFN-I response in host defense against infection caused by live bacteria (78).