Wenzel F, Baertl A, Zimmermann N, Hohlfeld Th, Giers G, Oldenburg J, Assert R
Zentrallabor, Universitätsklinikum Essen, Essen, Germany.
Clin Hemorheol Microcirc. 2008;39(1-4):417-22.
Biomarkers reflecting an inflammatory or immunological response are increasingly offered to improve the risk stratification of patients. For example, current evidence suggests that soluble CD40 ligand (sCD40L) is elevated in patients with acute coronary syndrome. But only a few data are available to evaluate the influence of preanalytic conditions on sCD40L values.
Blood samples of seven healthy blood donors were collected in tubes without additives and in EDTA- or citrate-filled tubes at various storage conditions. Platelet count was modified by serum dilution, and sCD40L was measured in platelet-rich-plasma and in whole blood. sCD40L levels were determined by an commercially available ELISA-Kit.
Immediately after blood sample assessment, sCD40L levels in serum samples were elevated (1258+/-820 pg/ml) compared to EDTA (64+/-32 pg/ml) and citrate (60+/-8.5 pg/ml) values. Additionally, sCD40L levels were dependent on storage duration. After platelet activation, sCD40L levels were significantly increased to 8278+/-2453 pg/ml and were significantly correlated to platelet count (r=0.96).
Soluble CD40L levels were clearly influenced by preanalytical conditions and were dependent on storage duration, sample technique and platelet count. These influences should be considered by the determination and evaluation of sCD40L concentrations.
反映炎症或免疫反应的生物标志物越来越多地用于改善患者的风险分层。例如，目前的证据表明，急性冠状动脉综合征患者的可溶性CD40配体（sCD40L）水平升高。但仅有少量数据可用于评估分析前条件对sCD40L值的影响。
采集7名健康献血者的血液样本，分别置于无添加剂试管、EDTA抗凝管或柠檬酸盐抗凝管中，并在不同储存条件下保存。通过血清稀释改变血小板计数，并在富血小板血浆和全血中测量sCD40L。sCD40L水平通过市售ELISA试剂盒测定。
血液样本采集后立即检测，血清样本中的sCD40L水平（1258±820 pg/ml）高于EDTA抗凝样本（64±32 pg/ml）和柠檬酸盐抗凝样本（60±8.5 pg/ml）。此外，sCD40L水平取决于储存时间。血小板激活后，sCD40L水平显著升高至8278±2453 pg/ml，且与血小板计数显著相关（r=0.96）。
可溶性CD40L水平明显受分析前条件影响，且取决于储存时间、样本采集技术和血小板计数。在测定和评估sCD40L浓度时应考虑这些影响因素。
