Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, Division of Cardiovascular Medicine, Stockholm, Sweden.
Thromb Haemost. 2012 Jun;107(6):1122-9. doi: 10.1160/TH11-11-0779. Epub 2012 Feb 28.
As microparticles are shedded upon platelet activation, and may be used to assess platelet function, we measured plasma concentrations of platelet-derived microparticles (PMPs) during and after an acute coronary syndrome (ACS). Fifty-one patients with ACS were investigated at admission, within 24 hours (before coronary angiography), and six months later. Sixty-one sex- and age-matched healthy controls were investigated once. PMPs were defined as particles <1.0 μm in size, negative to phalloidin (labels cell-fragments), and positive to CD61. Exposure of phosphatidylserine (PS+), CD62P and CD142 were also measured. Plasma concentrations of PS+PMPs exposing CD61, CD62P and CD142 were elevated 2.5, 6.0-, and 5.0-fold at admission (p<0.001 for all, compared to controls; aspirin only), decreased significantly 24 hours later following initiation of treatment with clopidogrel and subcutaneous anticoagulation (p<0.001 for all), and decreased even further six months later (p<0.01 for all). However, PS+PMPs exposing CD62P or CD142 were still between 1.2-and 2.3-fold higher than in controls (p<0.001 for both). The pattern for PS-PMPs during and after the ACS was very similar to that for PS+PMPs although the numbers were approximately 1/3 lower. In conclusion, PMP concentrations follow the pattern of platelet activation during and after an ACS. Decreased concentrations are observed after initiation of antithrombotic treatment, but PMP exposing CD62P or CD142 are still elevated after six months. Flow cytometric measurements of PMP in frozen-thawed samples enable studies of platelet function in larger clinical trials.
当血小板活化时会释放微粒体，并且可以用于评估血小板功能，我们在急性冠脉综合征（ACS）期间和之后测量了血浆中血小板衍生的微粒体（PMP）的浓度。在入院时、24 小时内（在冠状动脉造影之前）和 6 个月后，对 51 名 ACS 患者进行了调查。对 61 名性别和年龄匹配的健康对照者进行了一次调查。PMP 被定义为<1.0μm 大小的颗粒，对鬼笔环肽呈阴性（标记细胞碎片），对 CD61 呈阳性。还测量了暴露的磷脂酰丝氨酸（PS+）、CD62P 和 CD142。与对照组相比，在入院时，暴露于 PS+的 CD61、CD62P 和 CD142 的 PMPs 的血浆浓度升高了 2.5、6.0-和 5.0 倍（所有 p<0.001）；在开始使用氯吡格雷和皮下抗凝治疗 24 小时后，浓度显著降低（所有 p<0.001）；6 个月后，浓度进一步降低（所有 p<0.01）。然而，暴露于 PS+的 CD62P 或 CD142 的 PMPs 仍比对照组高 1.2-2.3 倍（两者均为 p<0.001）。ACS 期间和之后 PS-PMP 的模式与 PS+PMP 非常相似，尽管数量大约低 1/3。总之，PMP 浓度在 ACS 期间和之后与血小板活化的模式一致。在开始抗血栓治疗后，浓度降低，但在 6 个月后，暴露于 CD62P 或 CD142 的 PMPs 仍升高。冷冻解冻样本中 PMP 的流式细胞术测量可在更大的临床试验中研究血小板功能。
