MPPE1 and viral infectious disease: Compelling evidence from tumor and viral infection models (Bayerl et al., 2023; Böttcher et al., 2018; Brewitz et al., 2017; Alexandre et al., 2016; Domenjo-Vila et al., 2023), as well as metabolic disorders like non-alcoholic steatohepatitis (Deczkowska et al., 2021), has demonstrated the critical role of Xcr1+ cDC1 cells in diseases.