Figure 1. Integrin α_Dβ₂ is highly expressed on myeloid leukocytes in human blood.

A. Whole venous blood from healthy volunteers was fixed and expression of α_Dβ₂ on leukocyte subtypes was examined using mAb 169A (anti-α_D) and FITC-conjugated mAbs against CD14, CD15, and CD3 as described in Materials and Methods. The percent of each cell type positive for α_Dβ₂ is indicated by the bars. The error bars indicate the mean and SD of determinations using samples from four subjects. B. Monocytes were separated from venous blood of healthy volunteers and further separated into CD16⁺ and CD16⁻ CD14⁺ subpopulations as described in Materials and Methods. Surface expression of α_Dβ₂, α_Lβ₂, α_Mβ₂, and α_Xβ₂ was examined by flow cytometry using FITC- or ALEXA-488-conjugated antibodies and isotype-matched IgG controls. Cells in each monocyte fraction were also stained for CD14. These data indicate means and standard deviations in results from 3 experiments using samples from different subjects.