Fizet D, Bouzgarrou R, Piquet Y, Cristol G, Vezon G
CRTS de Bordeaux, France.
Ann Biol Clin (Paris). 1993;51(9):807-9.
Leukocyte contamination of various blood products is implicated in febrile transfusion reactions, in alloimmunization phenomena and immunosuppression, and in the transmission of viral infections. The biggest difficulty in interpreting published reports lies in the methods used to quantify residual leukocytes. As automated cell counters are not precise and sensitive enough to detect low cell counts, we compared two techniques: i) the classical method using the Nageotte haemocytometer; and ii) fluorescent staining with propidium iodide (PI). We performed these two techniques to evaluate the residual white cell count in 41 platelet units collected by cytapheresis. The difference in results obtained with the two techniques was borderline significant (P = 0.05). To evaluate the accuracy of both techniques, we added a known number of lymphocytes to platelet concentrates that had been filtered three times. There was a good correlation between the values obtained using the two techniques (r > 0.99). However, though the difference between the known value and PI results was not significant, the difference for Nageotte cell counter results was significant (P < 0.0001). From a practical point of view, the PI fluorescent technique is simple, rapid, and easy to carry out. Our results demonstrate the reliability of the PI technique for the evaluation of residual leukocytes.
各种血液制品中的白细胞污染与发热性输血反应、同种免疫现象和免疫抑制以及病毒感染的传播有关。解读已发表报告的最大困难在于用于量化残余白细胞的方法。由于自动细胞计数器不够精确和灵敏，无法检测到低细胞计数，我们比较了两种技术：i）使用纳盖奥特血细胞计数器的经典方法；ii）碘化丙啶（PI）荧光染色法。我们采用这两种技术评估了通过血细胞分离术采集的41个血小板单位中的残余白细胞计数。两种技术获得的结果差异接近显著（P = 0.05）。为了评估这两种技术的准确性，我们向经过三次过滤的血小板浓缩物中添加了已知数量的淋巴细胞。两种技术获得的值之间具有良好的相关性（r > 0.99）。然而，尽管已知值与PI结果之间的差异不显著，但纳盖奥特血细胞计数器结果的差异显著（P < 0.0001）。从实际角度来看，PI荧光技术简单、快速且易于实施。我们的结果证明了PI技术在评估残余白细胞方面的可靠性。
