Flow cytometric assessment of platelet aspirin resistance using light scattering.
BACKGROUND
A simple and reliable assay is needed for the prediction of the clinical efficacy of antiplatelet aspirin therapy. We have devised another method for the evaluation of platelet function and aspirin resistance (AR), via conventional flow cytometry (FCM).


METHODS
To devise an optimized protocol for the assessment of platelet AR, various analytic variables of FCM were investigated. Using this devised protocol, AR was assessed in healthy subjects as an example.


RESULTS
The protocol utilized herein is as follows: citrate-anticoagulated platelet-rich plasma was mixed 1:1 with HEPES-buffered saline in two tubes, one of which is treated with aspirin. During the acquisition of FCM, arachidonate is added to the tube. The response of the aspirin-treated platelets is then compared with those of nontreated ones on a time/forward scatter plot. In the 61 total subjects, none was identified as aspirin resistant by this assay.


CONCLUSIONS
Using light scattering, platelet aggregation and aspirin's antiplatelet effects can be readily and cost-effectively detected. According to this assay, biochemical AR appears to be rare. This new protocol may prove useful in a clinical setting or as a research tool.
Won
Dong Il
DI
Department of Clinical Pathology, Kyungpook National University School of Medicine, Daegu, Korea. wondi@knu.ac.kr
Yang
Dong Heon
DH
Kim
Dong Hyun
DH
Chae
Shung Chull
SC
Suh
Jang Soo
JS
D016718:Arachidonic Acid; D001241:Aspirin / Q000494:pharmacology*; D001681:Biological Assay / Q000295:instrumentation / Q000379:methods; D002021:Buffers; D004351:Drug Resistance / Q000502:physiology*; D005434:Flow Cytometry / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008027:Light; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D010976:Platelet Count / Q000295:instrumentation / Q000379:methods*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012542:Scattering, Radiation
D002021:Buffers; D010975:Platelet Aggregation Inhibitors; D016718:Arachidonic Acid; D001241:Aspirin