Jeppesen Jan Sommer, Breenfeldt Andersen Andreas, Bonne Thomas Christian, Thomassen Martin, Sørensen Helle, Nordsborg Nikolai Baastrup, Olsen Niels Vidiendal, Huertas Jesús Rodríguez, Bejder Jacob
Department of Nutrition, Exercise and Sports (NEXS), University of Copenhagen, Copenhagen, Denmark.
Data Science Lab, Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark.
Drug Test Anal. 2021 Jul;13(7):1331-1340. doi: 10.1002/dta.3031. Epub 2021 Mar 29.
We investigated whether immature reticulocyte fraction (IRF) and immature reticulocytes to red blood cells ratio (IR/RBC) are sensitive biomarkers for low-dose recombinant human erythropoietin (rhEpo) treatment at sea level (SL) and moderate altitude (AL) and whether multi (FACS) or single (Sysmex-XN) fluorescence flow cytometry is superior for IRF and IR/RBC determination. Thirty-nine participants completed two interventions, each containing a 4-week baseline, a 4-week SL or AL (2,230 m) exposure, and a 4-week follow-up. During exposure, rhEpo (20 IU kg ) or placebo (PLA) was injected at SL (SL , n = 25, SL n = 9) and AL (AL , n = 12, AL n = 27) every second day for 3 weeks. Venous blood was collected weekly. Sysmex measurements revealed that IRF and IR/RBC were up to ~70% (P < 0.01) and ~190% (P < 0.001) higher in SL than SL during treatment and up to ~45% (P < 0.001) and ~55% (P < 0.01) lower post-treatment, respectively. Compared with AL , IRF and IR/RBC were up to ~20% (P < 0.05) and ~45% (P < 0.001) lower post-treatment in SL , respectively. In AL , IRF and IR/RBC were up to ~40% (P < 0.05) and ~110% (P < 0.001) higher during treatment and up to ~25% (P < 0.05) and ~40% (P < 0.05) lower post-treatment, respectively, compared with AL . Calculated thresholds provided ~90% sensitivity for both biomarkers at SL and 33% (IRF) and 66% (IR/RBC) at AL. Specificity was >99%. Single-fluorescence flow cytometry coefficient of variation was >twofold higher at baseline (P < 0.001) and provided larger or similar changes compared to multi-fluorescence, albeit with smaller precision. In conclusion, IRF and IR/RBC were sensitive and specific biomarkers for low-dose rhEpo misuse at SL and AL.
我们研究了未成熟网织红细胞分数（IRF）和未成熟网织红细胞与红细胞比率（IR/RBC）是否是海平面（SL）和中度海拔（AL）下低剂量重组人促红细胞生成素（rhEpo）治疗的敏感生物标志物，以及多通道（FACS）或单通道（Sysmex-XN）荧光流式细胞术在测定IRF和IR/RBC方面是否更具优势。39名参与者完成了两项干预措施，每项干预措施包括4周的基线期、4周的SL或AL（2230米）暴露期以及4周的随访期。在暴露期间，在SL（SL组，n = 25，SL安慰剂组，n = 9）和AL（AL组，n = 12，AL安慰剂组，n = 27）每隔一天注射rhEpo（20 IU/kg）或安慰剂（PLA），共3周。每周采集静脉血。Sysmex测量结果显示，在治疗期间，SL组的IRF和IR/RBC分别比SL安慰剂组高约70%（P < 0.01）和约190%（P < 0.001），治疗后分别低约45%（P < 0.001）和约55%（P < 0.01）。与AL安慰剂组相比，SL组治疗后的IRF和IR/RBC分别低约20%（P < 0.05）和约45%（P < 0.001）。在AL组中，与AL安慰剂组相比，治疗期间IRF和IR/RBC分别高约40%（P < 0.05）和约110%（P < 0.001），治疗后分别低约25%（P < 0.05）和约40%（P < 0.05）。计算得出的阈值在SL时对两种生物标志物的敏感性约为90%，在AL时对IRF的敏感性为33%，对IR/RBC的敏感性为66%。特异性>99%。单通道荧光流式细胞术的变异系数在基线时高出两倍以上（P < 0.001），与多通道荧光相比，其变化幅度更大或相似，尽管精度较低。总之，IRF和IR/RBC是SL和AL下低剂量rhEpo滥用的敏感且特异的生物标志物。
