Erythropoietin (EPO) is a hormone, which stimulates the production of red blood cells. Due to its performance-enhancing effect, it is prohibited by the World Anti-Doping Agency (WADA). In order to reduce the detection window of EPO doping, athletes have been applying low doses of recombinant EPO (e.g., <10 IU/kg body weight, daily or every second day) instead of larger doses twice or more per week (e.g., 30 IU/kg). Microdoses of Retacrit (epoetin zeta), an EPO biosimilar, were administered intravenously and subcutaneously to human males and females. Urine and serum samples were collected and analysed applying the new biotinylated clone AE7A5 EPO antibody and a further optimized sarcosyl polyacrylamide gel electrophoresis (SAR-PAGE) protocol. With the improved protocol, microdosed Retacrit (7.5 IU/kg body weight [BW]) was detectable for at least 52 h after intravenous administration. Detection windows were approximately the same for serum and urine and doubled after subcutaneous administration (~104 h). Previous studies applying different electrophoretic techniques and the not further optimized SAR-PAGE protocol revealed considerably shorter detection windows for recombinant human erythropoietin (rhEPO) microdoses. Because the new biotinylated antibody performed significantly more sensitive than the nonbiotinylated version, the new protocol will improve the sensitivity and hence detectability of recombinant EPO in doping control.

中文翻译：

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来自应用新的生物素化克隆 AE7A5 抗体和进一步优化的肌氨酰聚丙烯酰胺凝胶电泳方案的微剂量重组人促红细胞生成素给药研究的数据

促红细胞生成素 (EPO) 是一种激素，可刺激红细胞的生成。由于其提高成绩的作用，被世界反兴奋剂机构 (WADA) 禁止。为了减少 EPO 兴奋剂的检测窗口，运动员一直使用低剂量的重组 EPO（例如，<10 IU/kg 体重，每天或每隔一天），而不是每周两次或更多次的大剂量（例如，30国际单位/千克）。微剂量的 Retacrit ( epoetin zeta)，一种 EPO 生物类似药，被静脉内和皮下注射给人类男性和女性。使用新的生物素化克隆 AE7A5 EPO 抗体和进一步优化的肌氨酰聚丙烯酰胺凝胶电泳 (SAR-PAGE) 方案收集和分析尿液和血清样本。通过改进的方案，微剂量 Retacrit（7.5 IU/kg 体重 [BW]）在静脉内给药后至少 52 小时内可检测到。血清和尿液的检测窗口大致相同，皮下给药后（~104 小时）加倍。以前的研究应用不同的电泳技术和未进一步优化的 SAR-PAGE 协议揭示了重组人促红细胞生成素 (rhEPO) 微剂量的检测窗口大大缩短。