IFNA1 and viral infectious disease: Mouse embryonic stem cells (ESCs) do not express IFN themselves upon viral infection but respond to IFN and display an attenuated innate immune response as compared with differentiated murine cells (Whyatt et al, 1993; Gonzalez-Navajas et al, 2012; Wang et al, 2013; Wang et al, 2014; Guo et al, 2015; D’Angelo et al, 2016; Guo, 2017).