To characterize, in an unbiased manner, the gene expression profile of the total viable CD45+ leukocytes specifically derived from the atherosclerosis-prone AA&R, and separately, from the more atheroresistant DT aortas of Apoe−/− mice fed either NCD for 16 weeks or HCD for 11 weeks, representing more advanced stages of lesion development, we used a screening approach of single cell transcriptomics. This evidence concerns the gene PTPRC and atherosclerosis.