Erythrocyte MP quantification in human plasma by fluorescence-activated cell sorter (FACS). Erythrocyte MPs were quantified as annexin-a5⁺/CD235⁺ double-positive events by FACS in control and sickle cell disease plasma vs calibrated fluorescent microbeads body. (A-B) Examples of stained annexin-a5⁺ and CD235a+ events in plasma: (A) control plasma and (B) SCD plasma. Modified from supplemental Figure 1 in the article by Camus et al that begins on page 3805.