Supplementary Material for: Platelet additive solutions SSP+ and T-PAS+ are interchangeable for platelet concentrate storage despite differences in composition and plasticizer

Introduction: Platelet additive solutions support ex vivo storage of platelet concentrates used for transfusion. The composition of platelet additive solutions within one generation (i.e. PAS-E) is similar but not identical. Additionally, the platelet additive solution storage bag may contain different plasticizers. This study compares the effect of two PAS-E solutions (SSP+ vs. T-PAS+, stored in a DEHP-containing and DEHP-free bag, respectively) to investigate if both additive solutions are interchangeable for platelet concentrate storage.
Methods: Platelet concentrates stored in plasma supplemented with SSP+ or T-PAS+ were compared by using a pool-and-split design. Platelet metabolism was investigated using a blood gas analyzer. The degree of platelet storage lesion was determined by flow cytometry to measure granule release and phosphatidylserine scrambling.
Results: The quality of platelet concentrates stored in either SSP+ or T-PAS+ is acceptable as pH decreased only slightly as a function of time. PH remained above 7.2 one day post expiration (day 6), which is far above the minimal criterium of 6.4. Platelet storage lesion was comparable between the two study groups with only limited α-granule release and phosphatidylserine surface expression in both groups after storage for five days, P = 0.547 and P = 0.825 respectively.
Conclusion: This study supports a safe switch between SSP+ and T-PAS+ storage solutions for platelet concentrates despite slight differences in storage solution composition and DEHP content.

引言：血小板添加剂溶液（Platelet additive solutions）可用于支持输血用血小板浓缩物（platelet concentrates）的体外储存。同一代次的血小板添加剂溶液（如PAS-E）组成虽相似但并不完全一致。此外，血小板添加剂溶液的储存袋可能含有不同种类的增塑剂。本研究对比两种PAS-E溶液（SSP+与T-PAS+，分别储存于含DEHP与不含DEHP的储存袋中）的效果，以探究二者是否可互换用于血小板浓缩物的储存。
方法：本研究采用混合分装设计（pool-and-split design），对比以血浆为基底添加SSP+或T-PAS+储存的血小板浓缩物。通过血气分析仪检测血小板代谢状态；采用流式细胞术（flow cytometry）检测颗粒释放与磷脂酰丝氨酸外翻情况，以此量化血小板储存损伤程度。
结果：采用SSP+或T-PAS+储存的血小板浓缩物质量均符合要求，随储存时间延长pH仅出现轻微下降。在有效期结束后1天（第6天），两组的pH值均高于7.2，远高于6.4的最低判定标准。两组的血小板储存损伤程度相当：储存5天后，两组的α颗粒释放程度与磷脂酰丝氨酸表面表达水平均较为有限，P值分别为0.547与0.825。
结论：尽管两种储存溶液的组成与DEHP含量存在细微差异，本研究结果支持血小板浓缩物可安全地在SSP+与T-PAS+储存溶液之间切换使用。