McArthur Lisa, Johnston Lisa, Sattar Naveed, Logue Jennifer, Welsh Paul
BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK.
BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
Ann Clin Biochem. 2015 Jan;52(Pt 1):165-8. doi: 10.1177/0004563214529550. Epub 2014 Apr 2.
It has been suggested that fetuin-A may be a potential biomarker of cardiometabolic disease. However, few studies have investigated preanalytical factors that might impact the measurement of fetuin-A in the circulation. This pilot study aimed to investigate the preanalytical variables of sample type, timing of sample centrifugation and the impact of freeze-thaw cycles on the concentration of fetuin-A in serum or EDTA-plasma.
Blood samples were taken from 19 male or female healthy volunteers, aged 18-70 years, and left at ambient room temperature for 2 h or 48 h. The tubes were then centrifuged, serum and EDTA-plasma separated, and fetuin-A concentrations measured using a commercially available enzyme-linked immunosorbent assay (ELISA).
There was no significant difference between the concentrations of fetuin-A in EDTA-plasma and serum following separation from whole blood at 2 h postcollection (P=0.78). The median (interquartile range) concentrations of fetuin-A in EDTA-plasma separated at 2 h and 48 h postcollection were 589 µg/mL (484-703 µg/mL) and 767 µg/mL (687-942 µg/mL), respectively (P<0.0005). For serum, equivalent concentrations were 606 µg/mL (501-669 µg/mL) at 2 h and 607 µg/mL (564-757 µg/mL) at 48 h postcollection (P=0.06). Fetuin-A concentrations measured in EDTA-plasma and serum showed no significant change following three freeze-thaw cycles in samples separated at 2 h postcollection (EDTA-plasma P=0.16; serum P=0.89).
This small pilot study has shown that serum is preferable to EDTA-plasma for the measurement of fetuin-A. It has also shown that fetuin-A appears to be as stable after three freeze-thaw cycles as it is after one.
有人提出胎球蛋白-A可能是心脏代谢疾病的潜在生物标志物。然而，很少有研究调查可能影响循环中胎球蛋白-A测量的分析前因素。这项初步研究旨在调查样本类型、样本离心时间等分析前变量以及冻融循环对血清或乙二胺四乙酸（EDTA）血浆中胎球蛋白-A浓度的影响。
从19名年龄在18至70岁的男性或女性健康志愿者身上采集血样，并在室温下放置2小时或48小时。然后将试管离心，分离出血清和EDTA血浆，使用市售的酶联免疫吸附测定（ELISA）法测量胎球蛋白-A浓度。
采血后2小时从全血中分离出的EDTA血浆和血清中，胎球蛋白-A的浓度没有显著差异（P = 0.78）。采血后2小时和48小时分离出的EDTA血浆中胎球蛋白-A的中位数（四分位间距）浓度分别为589μg/mL（484 - 703μg/mL）和767μg/mL（687 - 942μg/mL）（P < 0.0005）。对于血清，采血后2小时和48小时的等效浓度分别为606μg/mL（501 - 669μg/mL）和607μg/mL（564 - 757μg/mL）（P = 0.06）。在采血后2小时分离的样本中，经过三次冻融循环后测量的EDTA血浆和血清中的胎球蛋白-A浓度没有显著变化（EDTA血浆P = 0.16；血清P = 0.89）。
这项小型初步研究表明，在测量胎球蛋白-A时，血清优于EDTA血浆。研究还表明，胎球蛋白-A在经过三次冻融循环后的稳定性似乎与经过一次冻融循环后的稳定性相同。
