Loef Marieke, von Hegedus Johannes H, Ghorasaini Mohan, Kroon Féline P B, Giera Martin, Ioan-Facsinay Andreea, Kloppenburg Margreet
Department of Rheumatology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands.
Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands.
Metabolites. 2020 Dec 31;11(1):26. doi: 10.3390/metabo11010026.
It is essential to measure lipid biomarkers with a high reproducibility to prevent biased results. We compared the lipid composition and inter-day reproducibility of lipid measurements in plasma and erythrocytes. Samples from 42 individuals (77% women, mean age 65 years, mean body mass index (BMI) 27 kg/m), obtained non-fasted at baseline and after 6 weeks, were used for quantification of up to 1000 lipid species across 13 lipid classes with the Lipidyzer platform. Intraclass correlation coefficients (ICCs) were calculated to investigate the variability of lipid concentrations between timepoints. The ICC distribution of lipids in plasma and erythrocytes were compared using Wilcoxon tests. After data processing, the analyses included 630 lipids in plasma and 286 in erythrocytes. From these, 230 lipids overlapped between sample types. In plasma, 78% of lipid measurements were reproduced well to excellently, compared to 37% in erythrocytes. The ICC score distribution in plasma (median ICC 0.69) was significantly better than in erythrocytes (median ICC 0.51) (-value < 0.001). At the class level, reproducibility in plasma was superior for triacylglycerols and cholesteryl esters while ceramides, diacylglycerols, (lyso)phosphatidylethanolamines, and sphingomyelins showed better reproducibility in erythrocytes. Although in plasma overall reproducibility was superior, differences at individual and class levels may favor the use of erythrocytes.
为防止结果出现偏差，以高重现性测量脂质生物标志物至关重要。我们比较了血浆和红细胞中脂质测量的脂质组成及日间重现性。来自42名个体（77%为女性，平均年龄65岁，平均体重指数（BMI）为27kg/m²）的样本，在基线时和6周后非空腹采集，用于使用Lipidyzer平台对13种脂质类别中的多达1000种脂质进行定量。计算组内相关系数（ICC）以研究不同时间点脂质浓度的变异性。使用Wilcoxon检验比较血浆和红细胞中脂质的ICC分布。数据处理后，分析包括血浆中的630种脂质和红细胞中的286种脂质。其中，230种脂质在样本类型之间重叠。在血浆中，78%的脂质测量结果重现性良好至优秀，而在红细胞中这一比例为37%。血浆中的ICC评分分布（中位数ICC为0.69）明显优于红细胞（中位数ICC为0.51）（P值<0.001）。在类别水平上，血浆中三酰甘油和胆固醇酯的重现性较好，而神经酰胺、二酰甘油、（溶血）磷脂酰乙醇胺和鞘磷脂在红细胞中显示出更好的重现性。尽管血浆中的总体重现性较好，但个体和类别水平上的差异可能有利于红细胞的使用。
