Data from a microdosed recombinant human erythropoietin administration study applying the new biotinylated clone AE7A5 antibody and a further optimized sarcosyl polyacrylamide gel electrophoresis protocol

Effect of erythropoietin on SOFA score, Glasgow Coma Scale and mortality in traumatic brain injury patients: a randomized-double-blind controlled trial

Background

Recent studies suggest that erythropoietin has an anti-inflammatory effect on the central nervous system. The authors aimed to investigate the effect of erythropoietin on Glasgow Coma Scale (GCS), Sequential Organ Failure Assessment (SOFA) scores, and the mortality rate of traumatic brain injury (TBI) patients.

Methods

Sixty-eight patients with available inclusion criteria were randomly allocated to the control or intervention groups. In the intervention group, erythropoietin (4000 units) was administrated on days 1, 3, and 5. In the control group, normal saline on the same days was used. The primary outcomes were the GCS and SOFA score changes during the intervention. The secondary outcomes were the ventilation period during the first 2 weeks and the 3-month mortality rate.

Results

Erythropoietin administration significantly affected SOFA score over time (P=0.008), but no significant effect on the GCS, and duration of ventilation between the two groups was observed. Finally, erythropoietin had no significant effect on the three-month mortality (23.5% vs. 38.2% in the erythropoietin and control group, respectively). However, the mortality rate in the intervention group was lower than in the control group.

Conclusion

Our finding showed that erythropoietin administration in TBI may improve SOFA score. Therefore, erythropoietin may have beneficial effects on early morbidity and clinical improvement in TBI patients.

Assessing EPO stability in urine and comparing recombinant EPO detectability in matched urine, venous serum, and capillary serum following a controlled epoetin alfa administration

The instability of erythropoietin receptor agonists (ERAs, i.e., EPO) in urine presents a challenge to their detectability in doping control samples; however, this issue is not often seen in blood (serum) samples. With the anti-doping field beginning to transition into alternative blood collection technologies, it is important to understand recombinant EPO (rEPO) detectability in serum samples collected from one such capillary collection device, the Tasso+ SST. Twelve individuals were administered a single, 40 IU/kg dose of rEPO (epoetin alfa, EPOGEN®). Following administration, matched urine, venous serum, and capillary serum samples were concurrently collected. Urine aliquots were subject to various storage times and temperatures mimicking shipping conditions of doping control urine samples to assess EPO stability, while other urine aliquots, venous serum, and capillary serum aliquots were frozen until analysis to understand rEPO detectability across all three matrices. EPO and rEPO instability was identified in urine collected from 8 of 12 participants, especially in aliquots stored at room temperature and 37°C. In some of these unstable samples, rEPO was still detectable, while in others, no recombinant nor endogenous EPO was detectable and would have resulted in negative sample reports. Analyzing the concurrently collected urine, venous, and capillary serum samples, rEPO detectability was identical across the three matrices. In most cases, rEPO was detectable for at least 168 h post-administration. Noting greater stability in blood compared with urine, it is recommended that anti-doping authorities utilize this novel capillary serum collection technology to improve overall ERA detectability in doping control samples.

Evaluation of a single Eporatio® micro-dose in urine and dried blood spots

Recombinant human erythropoietin (rhEPO) has been abused as a performance enhancer in sports for several years, but with advancements in detection methods, even micro-doses can be detected in dried blood spot (DBS) samples. Here, we present the results from an Eporatio® (epoetin theta) micro-dose administration study to detect rhEPO in DBS samples. Five healthy male volunteers received a 15 IU/kg subcutaneous dose of Eporatio®. Urine and DBS samples (Mitra® VAMS and Capitainer® B50) were collected 1, 10, 24, 36, 48 and 72 h after drug administration. After 1 h, all urine samples were negative for rhEPO, whereas 40% of DBS samples were considered suspicious. All samples between 10 and 48 h were suspicious for the presence of Eporatio®, except one urine sample that was negative at 48 h. After 72 h, 40% of urine samples and 60% of DBS samples were suspicious and would have proceeded to a confirmation analysis. DBS is an efficient complementary matrix to urine for detection of rhEPO micro-doses.

Tracking immature reticulocyte proteins for improved detection of recombinant human erythropoietin (rhEPO) abuse

Athletes abuse recombinant human erythropoietin (rhEPO) and erythropoiesis stimulating agents to increase hemoglobin mass and improve performance. To evade detection, athletes have developed sophisticated blood doping regimens, which often include rhEPO micro-dosing. Detection of these methods requires biomarkers with increased sensitivity and a sample matrix that is more amenable to frequent testing in the field. We have developed a method to measure two immature reticulocyte proteins, CD71 and ferrochelatase (FECH), and one total erythrocyte protein, Band 3, in dried blood spots (DBS). This method was tested in response to rhEPO administration after low doses, 40 IU/kg, micro-doses, 900 IU, or saline injection in 20 healthy subjects. During administration of low-dose rhEPO, the mean CD71/Band 3 and FECH/Band 3 ratio increased by 412 ± 197% and 250 ± 44%, respectively. The mean response for the current biomarker, RET%, increased by 195 ± 35%. During administration of rhEPO micro-doses, CD71/Band 3 increased to 127 ± 25% on day 35 and 139 ± 36% on day 39, while no increase was observed in RET%. After rhEPO administration, during the washout phase, mean values decreased to a minimum of 64 ± 4% and 64 ± 11% for CD71/Band 3 and RET%, respectively. However, CD71/Band 3 remained below 75% of baseline for at least 4 weeks after rhEPO injection, while RET% returned to baseline levels. The results demonstrate that immature reticulocyte proteins have a larger response to rhEPO administration than the current biomarker, RET%, and can be monitored in the DBS matrix.

Transcriptomic Markers of Recombinant Human Erythropoietin Micro-Dosing in Thoroughbred Horses

Recombinant human erythropoietin (rHuEPO) is a well-known performance enhancing drug in human athletes, and there is anecdotal evidence of it being used in horse racing for the same purpose. rHuEPO, like endogenous EPO, increases arterial oxygen content and thus aerobic power. Micro-doping, or injecting smaller doses over a longer period of time, has become an important concern in both human and equine athletics since it is more difficult to detect. Horses offer an additional challenge of a contractile spleen, thus large changes in the red blood cell mass occur naturally. To address the challenge of detecting rHuEPO doping in horse racing, we determined the transcriptomic effects of rHuEPO micro-dosing over seven weeks in exercised Thoroughbreds. RNA-sequencing of peripheral blood mononuclear cells isolated at several time points throughout the study identified three transcripts (C13H16orf54, PUM2 and CHTOP) that were significantly (PFDR < 0.05) different between the treatment groups across two or three time point comparisons. PUM2 and CHTOP play a role in erythropoiesis while not much is known about C13H16orf54, but it is primarily expressed in whole blood. However, gene expression differences were not large enough to detect via RT-qPCR, thereby precluding their utility as biomarkers of micro-doping.

Discovery of c.577del in EPO: Investigations into endogenous EPO double-band detected in blood with SAR-PAGE

Recently, some athletes were repetitively found to have rEPO positive results, including a characterized double-band pattern in blood samples, in routine doping analysis. In contrast to previous findings from excretion studies, this double-band pattern showed the same relative intensity even when the samples were collected weeks (/months) apart. We therefore suspected that these "positive" doping control samples were related with a novel pathway of endogenous EPO production. Thus, follow-up investigations were warranted to characterize the origin of such analytical test results and to avoid the issuing of adverse analytical findings in the absence of rEPO by identifying the root cause of these "constantly positives." In this study, we designed and conducted a series of causal studies, including population screening of EPO profiles, exploration of EPO de-N-glycosylation, single nucleotide polymorphism (SNP) browsing in EPO, sequencing of EPO exons, genealogical analysis of the c.577del EPO variant, and finally expression and investigation of mutant EPO. In summary, we found that these "constantly positives" were related to endogenous EPO production associated with the c.577del EPO variant. The frequency of this variant was 0.39% in our Chinese population pool. The mutant EPO encoded by this variant is 27 amino acids longer than the wild-type. The molecular weight of this mutant EPO is approximately the same as that of rEPO, exhibiting a similar electrophoretic behavior. To prevent charges against carriers of the c.577del variant, a revised rEPO testing strategy has been implemented in the new version of TD EPO.

Annual banned-substance review: Analytical approaches in human sports drug testing 2020/2021

Most core areas of anti-doping research exploit and rely on analytical chemistry, applied to studies aiming at further improving the test methods' analytical sensitivity, the assays' comprehensiveness, the interpretation of metabolic profiles and patterns, but also at facilitating the differentiation of natural/endogenous substances from structurally identical but synthetically derived compounds and comprehending the athlete's exposome. Further, a continuously growing number of advantages of complementary matrices such as dried blood spots have been identified and transferred from research to sports drug testing routine applications, with an overall gain of valuable additions to the anti-doping field. In this edition of the annual banned-substance review, literature on recent developments in anti-doping published between October 2020 and September 2021 is summarized and discussed, particularly focusing on human doping controls and potential applications of new testing strategies to substances and methods of doping specified in the World Anti-Doping Agency's 2021 Prohibited List.

Detection of recombinant erythropoietin biosimilar JimaixinTM after administration in healthy subjects

Jimaixin^TM (Jintan Ltd, China) is a biosimilar of recombinant erythropoietin (rEPO) now authorized for therapeutic application in China. With a risk of abuse by athletes, a clear evaluation of its detection using the electrophoretic methods in use in antidoping laboratories was necessary. In a previous work, we showed that Jimaixin^TM electrophoretic profile presented slight changes compared to the original drug (first generation rEPO) and that a spike of Jimaixin^TM in urine and serum was well identified by SDS-PAGE but with less performance by IEF-PAGE unless a neuraminidase treatment was applied first. The aims of this research were to perform an intravenous administration of Jimaixin^TM on 3 healthy subjects (one microdose (10 IU/kg) and 3 therapeutic doses (50 IU/kg)) and to evaluate the detection in urine and blood up to 7 days post-administration. Analysis of the samples showed that Jimaixin^TM detection was complicated by IEF-PAGE due to the loss of the most distinctive basic isoforms. In addition, a neuraminidase treatment did not improve detection (contrary to the observations from spike experiments). On the contrary Jimaixin^TM was very efficiently detected in blood and urine by SDS-PAGE: up to 40h after a microdose and up to 7 days after the therapeutic doses. The effect of Jimaixin^TM on hematological parameters was limited to a clear but transitory increase of the reticulocytes. These data give new elements to better survey a potential misuse of Jimaixin^TM by athletes.