IFNAR1 and infection: Furthermore, B. coccoides colonization in Abx-treated mice endowed their BMDMs with the ability to induce ISG expression in an Ifnar-dependent manner, because ISG expression was undetectable (or extremely low) in BMDMs isolated from B. coccoides-colonized Ifnar−/− mice following EMCV infection at 8 hpi (Fig. 6B).