Atherosclerosis ATLO B-cell responses are specific, robust, highly territorialized, multilayered, and include a comprehensive adaptive B-2 and a substantial aberrant innate B-1 cell component: ATLOs but not WT adventitia harbor an unusual set of class-switched IgG1+, IgA+, and IgE+ B cells, a significant number of IL-10+/PD-L1+/FasL+/TGFβ+ B-1b cells, and both short-lived and long-lived PCs, including a fraction of IL-10+ PCs. Here, CD274 is linked to atherosclerosis.