ABSTRACT
Objective To establish a flow-cytometric method to detect microvesicles (MVs) in rat peripheral blood, and to detect platelets-derived MVs (PMVs) and endothelial cell-derived MVs (EMVs) in blood from ischemic precondition-ing (IPC) treated rats. Methods Blood was withdrawn from rat abdominal aorta and anticoagulated with sodium citrate. Platelets-free plasma (PFP) was isolated through two centrifugations at room temperature. PFP was incubated with FITC-conjugated mouse anti-rat CD61 or PE-conjugated mouse anti-rat CD144. Standard beads in diameter of 1 and 2μm were used for calibration and absolute counting, respectively. Analysis was performed on flow cytometer. Results When 3.5%so-dium citrate was mixed with blood at volume ratio of 1∶4, clear supernatant was collected after centrifugation. Signals of parti-cles smaller than 1μm accounted for more than 99%of overall signals. PMVs and EMVs were CD61 positive and CD144 positive, respectively. Their diameters were both smaller than 1 μm. The concentration of PMVs and EMVs in peripheral blood from IPC treated rats was (4 053±1 987)/μL and (4 870±825)/μL, respectively. Conclusion The method for MVs de-tection by flow cytometry was successfully established and optimized, and verified through detecting PMVs and EMVs in pe-ripheral blood from IPC treated rats.