Institute of Vascular Biology and Thrombosis Research, Centre of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria.
Institute of Vascular Biology and Thrombosis Research, Centre of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria.
Thromb Res. 2023 Mar;223:111-122. doi: 10.1016/j.thromres.2023.01.026. Epub 2023 Jan 27.
Platelets are primarily recognized for their role in hemostasis, but also regulate immune responses by interacting with leukocytes. Their highly sensitive nature enables platelets to rapidly respond to micro-environmental changes, which is crucial under physiological condition but can jeopardize in vitro analyses. Thus, we tested how platelet count and changes in pH and temperatures, which are commonly experienced during inflammation and infection but also affected by ex vivo analyses, influence platelet-leukocyte interaction and immunomodulation. Reducing platelet count by up to 90 % slightly decreased platelet activation and platelet-leukocyte aggregate formation, but did not affect CD11b activation nor CD62L shedding of monocytes or neutrophils. Acidosis (pH 6.9) slightly elevated platelet degranulation and binding to innate leukocytes, though pH changes did not modulate leukocyte activation. While platelet responsiveness was higher at room temperature than at 37 °C, incubation temperature did not affect platelet-leukocyte aggregate formation. In contrast, platelet-mediated CD11b activation and CD62L expression increased with temperature. Our data thus demonstrate the importance of standardized protocols for sample preparation and assay procedure to obtain comparable data. Further, unspecific physiologic responses such as thrombocytopenia, acidosis or temperature changes may contribute to platelet dysfunction and altered platelet-mediated immunomodulation in inflammatory and infectious disease.
血小板主要因其在止血中的作用而被认识，但它们也通过与白细胞相互作用来调节免疫反应。它们高度敏感的特性使血小板能够迅速响应微环境变化，这在生理条件下至关重要，但在体外分析中可能会带来风险。因此，我们测试了血小板计数以及 pH 值和温度的变化如何影响血小板-白细胞相互作用和免疫调节，这些变化在炎症和感染期间很常见，但也受到体外分析的影响。将血小板计数减少高达 90%会轻微降低血小板活化和血小板-白细胞聚集体形成，但不会影响单核细胞或中性粒细胞的 CD11b 活化或 CD62L 脱落。酸中毒（pH 6.9）会轻微增加血小板脱颗粒和与先天白细胞的结合，但 pH 值变化不会调节白细胞活化。虽然血小板在室温下比在 37°C 下的反应性更高，但孵育温度不会影响血小板-白细胞聚集体形成。相比之下，血小板介导的 CD11b 活化和 CD62L 表达随温度升高而增加。因此，我们的数据表明，为了获得可比的数据，标准化的样本制备和检测程序对于实验非常重要。此外，非特异性的生理反应，如血小板减少症、酸中毒或温度变化，可能导致血小板功能障碍和炎症性疾病和感染性疾病中血小板介导的免疫调节改变。
