Platelet-adherent leukocytes are identifiable in peripheral blood. (A) Representative histograms of platelet-adherent eosinophils (identified as CCR3⁺CD45⁺ cells in the granulocyte side scatter [SSC] gate), neutrophils (CD16⁺CD45⁺ cells in the granulocyte SSC gate), monocytes (CD45⁺ in the monocyte SSC gate), and lymphocytes (CD45⁺ cells in lymphocyte SSC gate) in blood from an ATA control (top) and a subject with AERD (bottom). The percentages of each cell type with adherent platelets are shown. (B) Percentages of leukocytes with adherent platelets (as determined by staining with CD61) in blood of nonasthmatic controls (n = 9), ATA controls (n = 13), and subjects with AERD (n = 15). Data are expressed as mean + SD (★P < .001).