Detection of platelet-derived microparticles using flow cytometry and its clinical application.
OBJECTIVE
To establish a flow cytometric internal standard method for counting platelet-derived microparticles (PMPs) and to study its clinical significance.


METHODS
PMPs suspension (platelet poor plasma, PPP) was extracted by gradual centrifugation. According to the size of PMPs, 3 microm and 0.8 microm latex beads were used as internal standards for the quantitation. PMPs were counted by adjusting flow cytometric discrimination and voltage of forward scatter and side scatter.


RESULTS
In 30 healthy donors, the average concentration of resting PMPs was (1.2 x 10(5) +/- 5.7 x 10(4))/ml and that of activated PMPs was (1.6 x 10(6) +/- 9.1 x 10(5))/ml. Compared with healthy donors, PMPs mean value was significantly higher (P < 0.001) in 18 patients with coronary artery disease, 12 with acute cerebral infraction and 23 with chronic renal failure [the average PMPs concentration, (6.1 x 10(5) +/- 2.5 x 10(5))/ml, (6.8 x 10(5) +/- 3.4 x 10(5))/ml and (5.9 x 10(5) +/- 3.1 x 10(5))/ml respectively]. However, no significant difference in PMPs concentration was observed in 25 patients with acute leukemia and severe thrombocytopenia during the aplastic phase after chemotherapy [(1.3 x 10(5) +/- 6.1 x 10(4))/ml, (P > 0.05)].


CONCLUSIONS
PMPs is a useful indicator in monitoring platelet activation, and plays an important role in thrombotic disease. By flow cytometric internal standard method, PMPs can be counted rapidly and accurately, which may be very helpful in interlaboratory comparative studies.
Cui
Wei
W
Department of Clinical Laboratory, Peking Union Medical College Hospital, CAMS & PUMC, Beijing 100730. cuiwei@pumch.ac.cn
Ma
Wenxin
W
Han
Yehua
Y
Lin
Qisui
Q
D000293:Adolescent; D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000737:chemistry* / Q000648:ultrastructure; D002462:Cell Membrane / Q000737:chemistry* / Q000648:ultrastructure; D002648:Child; D002675:Child, Preschool; D003327:Coronary Disease / Q000097:blood; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood; D008875:Middle Aged; D010316:Particle Size; D015539:Platelet Activation; D010976:Platelet Count; D010980:Platelet Membrane Glycoproteins / Q000032:analysis; D012015:Reference Standards
D010980:Platelet Membrane Glycoproteins