Feys H B, Coene J, Devloo R, Van Aelst B, Pottel H, Vandekerckhove P, Compernolle V
Transfusion Research Center, Belgian Red Cross-Flanders, Ghent, Belgium.
Vox Sang. 2015 May;108(4):368-77. doi: 10.1111/vox.12243. Epub 2015 Mar 6.
Aggregates often appear during apheresis. Sometimes, these persist throughout storage, causing product wastage. This study assessed product quality of apheresis concentrates containing persistent aggregates (PA) and aimed to identify the factors that contribute to their formation.
Donation (n = 180) and platelet indices (n ≥ 10) from apheresis concentrates with PA were compared with aggregate-free products.
The proportion of donors with at least one previous PA donation was twofold higher in the PA group (P < 0·0001) indicating a donor dependence. Significantly higher donor whole blood platelet counts (286 ± 50 vs. 266 ± 49 × 10(3) /μl, P < 0·0001) and higher apheresis yields (6·0 ± 1·6 vs. 5·4 ± 1·5 × 10(11) , P < 0·0001) were noted in the PA group. Haematocrit was also slightly higher, but age, gender and body mass were similar. The pH of PA products on day six postdonation was significantly lower (P < 0·001), in line with higher lactic acid concentrations. Flow cytometry showed no differences in GPIbα levels or phosphatidylserine exposure. However, there was slightly more integrin activation as well as increased degranulation measured by P-selectin expression. Cytokine concentrations were also significantly higher in PA concentrates. Aggregation was normal in response to SFLLRN peptide and collagen stimulation, but agglutination at low-dose ristocetin was significantly higher (P = 0.01) in PA products. Finally, PA were disintegrated by plasmin-mediated thrombolysis but not by integrin αIIb β3 inhibition.
Products with PA have acceptable quality parameters, but additional functional studies are warranted. Furthermore, PA are more likely to recur in certain donors who have higher platelet counts.
单采过程中常常出现聚集物。有时，这些聚集物在储存过程中持续存在，导致产品浪费。本研究评估了含有持续性聚集物（PA）的单采浓缩物的产品质量，并旨在确定促成其形成的因素。
将含有PA的单采浓缩物的献血样本（n = 180）和血小板指数（n≥10）与无聚集物的产品进行比较。
PA组中至少有一次既往PA献血的献血者比例是无PA组的两倍（P < 0.0001），表明存在献血者依赖性。PA组的献血者全血血小板计数显著更高（286±50对266±49×10³/μl，P < 0.0001），单采产量也更高（6.0±1.6对5.4±1.5×10¹¹，P < 0.0001）。血细胞比容也略高，但年龄、性别和体重相似。献血后第6天PA产品的pH值显著更低（P < 0.001），这与更高的乳酸浓度一致。流式细胞术显示糖蛋白Ibα水平或磷脂酰丝氨酸暴露无差异。然而，整合素激活略有增加，同时通过P-选择素表达测量的脱颗粒增加。PA浓缩物中的细胞因子浓度也显著更高。对SFLLRN肽和胶原刺激的聚集反应正常，但PA产品中低剂量瑞斯托菌素诱导的凝集显著更高（P = 0.01）。最后，PA可通过纤溶酶介导的溶栓作用解体，但不能通过整合素αIIbβ3抑制作用解体。
含有PA的产品具有可接受的质量参数，但有必要进行额外的功能研究。此外，PA更有可能在某些血小板计数较高的献血者中再次出现。
