Fent János, Bihari Péter, Furész József, Hamar János, Lakatos Susan
Department of Pathophysiology, Research Institute of Military Health Center, Budapest, Hungary.
J Biochem Biophys Methods. 2008 Apr 24;70(6):1086-90. doi: 10.1016/j.jbbm.2007.07.008. Epub 2007 Aug 7.
Cell complexes composed of two different cells labeled with different fluorophores can be detected as double positive events in the flow cytometer. Double positivity can originate not only from real complexes but from non-interacting coinciding cells as well. Coincidence has a high impact on the determination of the amount of platelet-granulocyte complexes since platelet concentration is in the orders of magnitude higher than that of the granulocytes. A computer model has been developed to simulate coincidence in the flow cytometer to reveal the contribution of coincidence to the overestimation of the total amount of platelet-granulocyte complexes. Mixtures of non-interacting fluorescent beads as well as EDTA-anticoagulated blood samples were analyzed in the flow cytometer. An excellent fit was found between computer simulated and measured data pairs. Bead mixture in the flow cytometer and simulation of that resulted in 37.3+/-1.3 and 35.7+/-0.6% double positivity, respectively. 30.2+/-4.3% double positivity was measured for EDTA-anticoagulated blood samples while simulation of that resulted in 28.3+/-0.6%. Double positivity attributed to platelet-granulocyte complexes in slightly diluted blood samples might originate in coincidence and not from true complexes.
由用不同荧光团标记的两种不同细胞组成的细胞复合体，在流式细胞仪中可被检测为双阳性事件。双阳性不仅可能源于真正的复合体，也可能源于非相互作用的巧合细胞。巧合对血小板 - 粒细胞复合体数量的测定有很大影响，因为血小板浓度比粒细胞浓度高几个数量级。已开发出一种计算机模型来模拟流式细胞仪中的巧合情况，以揭示巧合对血小板 - 粒细胞复合体总量高估的贡献。在流式细胞仪中分析了非相互作用荧光珠的混合物以及乙二胺四乙酸（EDTA）抗凝的血液样本。发现计算机模拟数据对与测量数据对之间拟合良好。流式细胞仪中的珠混合物及其模拟分别产生了37.3±1.3%和35.7±0.6%的双阳性率。EDTA抗凝血液样本的双阳性率测量值为30.2±4.3%，而模拟值为28.3±0.6%。轻度稀释血液样本中归因于血小板 - 粒细胞复合体的双阳性可能源于巧合而非真正的复合体。
