IL1RAP blockade reduces plaque burden. (A) Female Apoe^−/− mice were treated biweekly with i.p. injections of either anti-IL1RAP antibody or control isotype IgG (Ctrl IgG) (n = 14/group) for 6 weeks, for a total of 10 weeks HCD. (B) Representative lipid staining (Oil Red O) of HCD-fed Apoe^−/− mice treated with anti-IL1RAP antibodies or isotype. (C) Quantification of average subvalvular plaque area progressing through the aortic valve. Dots denote average of all mice in each treatment group at indicated distance within the aortic valve. Quantification of (D) average plaque area (P = 0.0016) and (E) plaque volume (P = 0.0016). (F) Representative collagen staining (Masson’s trichrome) and (G) quantification of relative collagen area in aortic root plaques. (H) Total plasma cholesterol levels. Analysed with Student’s unpaired t-test.