Expression of integrins by platelet-adherent and -nonadherent leukocyte subsets. (A) Representative histograms of relative CD18 expression by CD61⁻ platelet-nonadherent (solid gray) and CD61⁺ platelet-adherent (black line) peripheral blood eosinophils (top), neutrophils (middle), and monocytes (bottom) are shown for a subject with AERD. (B-D) Relative expression of CD18 and CD49d on eosinophils (B), CD18 on neutrophils (C), and CD18 and CD11b on monocytes (D), comparing the platelet-adherent and platelet-nonadherent leukocyte subsets in nonasthmatic controls (n = 7), ATA controls (n = 10), and subjects with AERD (n = 9). MFI indicates mean fluorescence intensity. Platelet-free CD61⁻ leukocyte subsets are shown in white columns, and CD61⁺ leukocyte subsets are shown in hatched columns. Data are expressed as mean + SEM (★P < .05, ★★P < .01, ★★★P < .001).