Guo Jing, Schupf Nicole, Mayeux Richard P, Gu Yian
Taub Institute for Research in Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY USA.
Department of Neurology, Columbia University, New York, NY USA.
Immun Ageing. 2020 Oct 13;17:29. doi: 10.1186/s12979-020-00201-0. eCollection 2020.
It is important to assess the temporal reproducibility of circulating cytokines for their utility in epidemiological studies. However, existing evidence is limited and inconsistent, especially for the elderly population.
Sixty-five elderly (mean age = 77.89 ± 6.14 years) subjects were randomly selected from an existing prospective cohort study. Levels of 41 cytokines in 195 serum samples, collected at three separate visits that were up to 15.26 years apart, were measured by the Luminex technology. The temporal reproducibility of cytokines was estimated by the intraclass correlation coefficient (ICC) calculated using a mixed-effects model. In addition, data analyses were stratified by the median (4.49 years) of time intervals across sample collection. Sensitivity analyses were performed when excluding subjects with undetectable samples.
A total of 23 cytokines were detectable in more than 60% of samples. Fair to good (ICC = 0.40 to 0.75) and excellent (ICC > 0.75) reproducibility was found in 10 (Eotaxin, VEGF, FGF-2, G-CSF, MDC, GM-CSF, TGFα, IP-10, MIP-1β, IL-1RA) and 5 (GRO, IFNγ, IL-17, PDGF-AA, IL-4) cytokines, respectively. The results were not changed dramatically in the stratification and sensitivity analyses.
Serum levels of the selected 15 cytokines measured with Luminex technology displayed fair to excellent within-person temporal reproducibility among elderly population.
评估循环细胞因子在流行病学研究中的效用时，其时间再现性很重要。然而，现有证据有限且不一致，尤其是在老年人群中。
从一项现有的前瞻性队列研究中随机选取65名老年人（平均年龄=77.89±6.14岁）。通过Luminex技术测量在三次单独访视时收集的195份血清样本中41种细胞因子的水平，访视间隔时间长达15.26年。使用混合效应模型计算组内相关系数（ICC）来估计细胞因子的时间再现性。此外，数据分析按样本采集时间间隔的中位数（4.49年）进行分层。排除样本检测不到的受试者后进行敏感性分析。
在超过60%的样本中可检测到总共23种细胞因子。分别在10种（嗜酸性粒细胞趋化因子、血管内皮生长因子、成纤维细胞生长因子-2、粒细胞集落刺激因子、巨噬细胞衍生趋化因子、粒细胞-巨噬细胞集落刺激因子、转化生长因子α、干扰素γ诱导蛋白10、巨噬细胞炎性蛋白-1β、白细胞介素-1受体拮抗剂）和5种（生长调节致癌基因、干扰素γ、白细胞介素-17、血小板衍生生长因子-AA、白细胞介素-4）细胞因子中发现了中等至良好（ICC=0.40至0.75）和优秀（ICC>0.75）的再现性。分层和敏感性分析结果没有显著变化。
使用Luminex技术测量的所选15种细胞因子的血清水平在老年人群中显示出中等至优秀的个体内时间再现性。
