Blood transcriptional signature of recombinant human erythropoietin administration and implications for antidoping strategies

Abstract

Recombinant human erythropoietin (rHuEPO) is frequently abused by athletes as a performance-enhancing drug, despite being prohibited by the World Anti-Doping Agency. Although the methods to detect blood doping, including rHuEPO injections, have improved in recent years, they remain imperfect. In a proof-of-principle study, we identified, replicated, and validated the whole blood transcriptional signature of rHuEPO in endurance-trained Caucasian males at sea level (n = 18) and Kenyan endurance runners at moderate altitude (n = 20), all of whom received rHuEPO injections for 4 wk. Transcriptional profiling shows that hundreds of transcripts were altered by rHuEPO in both cohorts. The main regulated expression pattern, observed in all participants, was characterized by a "rebound" effect with a profound upregulation during rHuEPO and a subsequent downregulation up to 4 wk postadministration. The functions of the identified genes were mainly related to the functional and structural properties of the red blood cell. Of the genes identified to be differentially expressed during and post-rHuEPO, we further confirmed a whole blood 34-transcript signature that can distinguish between samples collected pre-, during, and post-rHuEPO administration. By providing biomarkers that can reveal rHuEPO use, our findings represent an advance in the development of new methods for the detection of blood doping.

Transcriptomic biomarkers of altered erythropoiesis to detect autologous blood transfusion

“…Based on the blood transcriptional signature of recombinant human EPO (rHuEPO), Salamin et al demonstrated that delta‐aminolevulinate synthase 2 ( ALAS2 ), carbonic anhydrase ( CA1 ), and solute carrier family 4 member 1 ( SLC4A1 ) were down‐regulated after reinfusion of donated blood . Using a different method of quantitation (RT‐qPCR), we confirmed the results of this pilot study with additional subjects ( n = 15 vs 7) and time points tested ( t = 8 vs 5) (Figure A).…”

“…It suggests that transcriptomic biomarkers might be promising complements to hematological parameters of the ABP in a longitudinal monitoring for the detection of transfusion. Moreover, as demonstrated by Durussel et al, these genes might also serve as biomarkers of rHuEPO administration …”

Annual banned‐substance review: analytical approaches in human sports drug testing

“…An alternative strategy for identifying EPO misuse in doping controls was presented by Durussel et al ., who investigated the effect of EPO injections on the whole blood transcriptional signature . A drug intervention study was conducted with 18 Caucasian and 18 African trained volunteers, who received 50 IU/kg every two days over a period of 4 weeks.…”

RNA stabilized blood tubes to measure haemoglobin concentration

“…Previously, Salamin et al suggested that measurements of gene transcripts from reticulocytes in RNA stabilized blood tubes could be biomarkers of blood transfusion . It was also demonstrated that the same strategy was applicable for the detection of erythropoietin stimulating agents in micro‐doses . RNA stabilized blood tubes such as Tempus™ blood RNA tubes are mainly used for multi‐site clinical studies in order to facilitate the transport and storage of samples .…”