APOE and atherosclerosis: To understand the role of Xcr1+ cDC1 in regulating the development of atherosclerosis, we established the Xcr1Cre-Gfp Apoe–/– mice in which the Cre recombinase and eGFP was co-expressed under the control of the endogenous Xcr1 promoter following the start codon (Figure 2—figure supplement 1).