We conducted a comparison of scRNA-seq on four paired fresh and cryopreserved atheroma samples, two from coronary arteries and two from carotid arteries, to determine whether it is possible to obtain comparable data from frozen samples. After enzymatic digestion into single cell suspensions, we sorted CD45+ cells from half of each sample and immediately processed these using the 10X Genomics scRNA-seq workflow after collection, while the other half was frozen in liquid nitrogen. After cryopreservation for an average of 7 days, the other half of each sample was thawed and sorted identically to the fresh samples. Overall design: scRNA-seq of four paired fresh and cryopreserved atheroma samples