Analysis of human chorionic gonadotropin (hCG): Application of routine immunological methods for initial testing and confirmation analysis in doping control

Abstract

Human chorionic gonadotropin (hCG) is dimeric glycoprotein produced by placenta in pregnancy and also in low levels by pituitary gland. The main clinical use for exogenous hCG-administration is typically linked to infertility. The desired effect of hCG misuse in sport is due to the enhancement of testicular production of testosterone. Therefore, hCG is listed by the World Anti-Doping Agency (WADA) as a prohibited substance in male athletes and according to the recently published WADA guideline urinary concentrations of hCG > 5 IU/L may be an indicator of doping. In this study two independent immunoassays were used to implement the new WADA guideline. The assay for initial testing (Siemens Immulite 2000 XPi hCG assay) recognizes various hCG variants (e.g. hCG and β-core fragment of hCG) whereas the confirmatory assay (PerkinElmer DELFIA Xpress hCG) is sensitive to intact and nicked hCG only. Both assays showed adequate sensitivity and were proven fit-for-purpose in routine doping control. Population-based distribution of the assays was in good agreement with results of earlier studies and supported well the current threshold of 5 IU/L.

Development and validation of a liquid chromatography–mass spectrometry procedure after solid-phase extraction for detection of 19 doping peptides in human urine

“…Finally, novel, previously unknown macromolecules (i.e., TB500 17-23 fragment), with no current approval for human therapeutic use (i.e., agents under preclinical or clinical development, designer drugs, or compounds approved only for veterinary use), but illegally marketed (e.g., via Internet websites) [5] are included in section S0 ''Non-approved substances''. Different analytical approaches have already been developed and published to detect these compounds in nutritional supplements [6][7][8][9][10] and in doping control samples (either blood [11][12][13][14][15][16][17][18] or urine [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]), employing immunological [26,[35][36][37], electrophoretic [16][17][18][19]27], or liquid chromatography-mass spectrometry techniques [6-15, 20-25, 28-34] or a combination of different analytical technologies. In general, the most effective analytical approach (combined sample pretreatment and the instrumental method) has to take into ...…”

Urine reference intervals for human chorionic gonadotropin (hCG) isoforms by immunoextraction–tandem mass spectrometry to detect hCG use

“…This has been shown when hCG positive urine samples from excretion studies and atypical urine samples with total hCG concentrations >5 IU/L were analyzed using the Roche intact hCG immunoassay and the LC–MS/MS method . In addition, the Immulite total hCG immunoassay has also been shown to produce hCG concentrations as high as 4.9 IU/L when 1199 urine samples from male athletes were analyzed . These data indicate that separate hCG thresholds are needed depending upon the method used for quantification of hCG (immunoassay versus LC–MS/MS), which have been provided in the WADA technical document TD2017CG/LH…”

“…Based on these data, a threshold of 1.0 IU/L for urinary 9,15 In addition, the Immulite total hCG immunoassay has also been shown to produce hCG concentrations as high as 4.9 IU/L when 1199 urine samples from male athletes were analyzed. 16 These data indicate that separate hCG thresholds are needed depending upon the method used for…”

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

“…[104] While the initial testing assay recognizes several different hCG variants including the intact heterodimeric hCG and the β-core fragment of hCG, the Delfia Xpress confirmation test detects intact hCG and nicked hCG only. Today, two immunoassays are recommended by WADA to be used as initial testing and confirmation tools.…”