Blood doping: is it effective? Brien AJ, Simon TL. Effects of red blood cell infusion on 10-km race time. JAMA 1987

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1 Blood doping the attempt to increase the total amount of circulating hemoglobin (and oxygen transport to tisses) through illegal practices used since 70s in endurance sports diffused during 90s to now

2 Blood doping: is it effective? Brien AJ, Simon TL. Effects of red blood cell infusion on 10-km race time. JAMA 1987

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4 The hierarchic organization of hematopoiesis Stem cells Self-renewal Progenitor cells Differentiation Proliferation Maturativeproliferative compartment Function & death

5 Erythroid progenitors in colture

6 A rapid response to tissue oxygenation in the kidneys changes the rate of erythropoietin production

7 Hypoxia Inducible Factor 1 (HIF-1) Hypoxia inducing factor is a specific protein involved in maintaining oxygen homeostasis and regulates hypoxia inducible genes that include human erythropoietin (EPO) gene HIF-1 is a a heterodimer double helix loop and is the transcriptional factor that is needed for the activation mediated by EPO gene enhancer in hypoxic cells. HIF-1 alpha is upregulated when there is lack of oxygen and heterdimerizes with the receptor nuclear translocator also known as the HIF-1 beta. The heterodimer complex binds and activates transcription of target genes.

8 HYPOXIC INDUCTION OF THE EPO GENE

9 EPO Catene laterali carboidrato Recettore 1 (66 kd, member of the cytokine receptor superfamily) Recettore 2

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16 lug-95 mag-95 HCT: seasonal variation in cyclists mar-95 gen-95 nov-94 set-94 lug-94 mag-94 mar-94 gen-94 nov-93 set-93 lug

17 3/3/ HCT in elite cross-country skiers 27/10/93 11/12/93 23/1/94 9/2/94 3/3/94 28/9/94 3/12/94 21/1/95 5/8/93 10/11/92

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19 Blood doping 2 Is blood doping dangerous?

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21 Plasma ferritin in a professional cyclist /11/ /01/ /03/ /03/ /04/ /04/ /05/ /05/ /05/ /06/ /11/ /04/1998

22 22 /11 / /01 / /03 / /04 / /05 / /05 / /06 / /08 / /12 / /01 / /03 / /04 / /05 / /06 / / Hematocrit fall in a professional cyclist due to out-of-season phlebotomies to reduce iron overload

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25 EPO is a promising drug in stroke therapy

26 Blood doping 3 Can blood doping be directly detected?

27 rhuepo doping detection: direct methods urine (and/or blood) analysis by isoelectric focusing and a double blotting procedure

28 2008 positive doping cases in cyclism

29 Problems with direct EPO urine detection time window: urine detection only for 2-3 days microdosages, new types of Epo proteases and dilution are used to cheat interpretation can be difficult new biosimilar products The answer: indirect methods based on blood cell count and longitudinale blood profile

30 Minor populations of antigen-positive and negative erythrocytes K+ in K- K- in K+ s+ in s- s- in s+

31 Autologous doping transfusion no direct method available research studies in progress indirect methods based on blood cell count There is no doubt, although scientific experiment have not been published, that reinfusion of heterologous blood could be detected using sophisticated haematological methods and DNA techniques. However, autologous reinfusion of whole blood or packed red cells cannot be detected. More research is necessary in this area B.T. Ekblom. Blood boosting and sport. Ballières clinical endocrinology and metabolism. 14:89-98, 2000

32 Blood doping 3 Indirect detection: the ABP

33 Blood antidoping: indirect methods based blood cell analysis hemoglobin reticulocyte count off score useful for all types of blood doping used for targeting suspect athletes possible decision for antidoping rule violation (ADRV) in the context of an athlete biologic passport (blood profile)

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35 The OFF score to detect the post-administration phase characterized by still high hemoglobin and low reticulocytes (inhibition) calculated as: OFF score: Hb-60 ret% high value: > low value (associated with reticulocytosis)

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38 Definition of indirect blood antidoping Identification through laboratory hematological (not toxycological) tests of abnormalities using: POPULATION REFERENCE VALUES (inter-individual differences). A single blood count result (i.e. high hemoglobin or hematocrit) This was the basis for the application in1997 of a threshold to suspend athletes for health reasons INDIVIDUAL REFERENCE VALUE (intraindividual differences). Hematological stability permits the evaluation of unexpected changes in blood results in a single subject: use of longitudinal data or critical difference between measurements. The monitored sequence of results within a structured follow-up program of in and outof-competitions controls (blood profile).

39 The new WADA Code: January 2009 For the first time, the new WADA Code allows sanctions to be imposed not only in the case of a positive doping test or conclusively proven manipulation, but also in the case of evidence inferring the use of a prohibited method for performance enhancement. Use or Attempted Use may also be established by other reliable means such as admissions, witness statements, documentary evidence, conclusions drawn from longitudinal profiling, or other analytical information This opens new possibilities for indirect blood antidoping as a mean for sanctioning

40 Parameters and Limits (UCI) Parameters Year of introduction Limit for men Limit for women Ht (%) 1997 > 50% > 47% Hb (g/dl) 2000 > 17 g/dl > 16 g/dl Free plasma Hb (mg/dl) 2003 > 300 mg/dl Stimulation index [Sysmex] = Hb (g/l) - 60 ret (%) (OFF) Ret (%) [Sysmex] % If values beyond limits: no start and inaptitude for 15 days

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42 Experimental administration of rhuepo to athletes D0 D10 D14 D21 A1 A7 A14 A25 HCT HGB RET rhuepo 9 athletes during training (Audran M et al., 1999) Eprex Cilag 50 UI/kg/die s.c. for 26 days

43 Reticulocytes Evolution in cyclists (UCI) < 0.2 < 0.4 > 2.0 >

44 The Athlete s Biological Passport WADA UCI IAAF - NADO cooperation, with a group of international expert based on repeated individual measurement of: Hb g/l reticulocyte percentage OFF score uses Bayesian statistics to provide personal limits instead of population limits

45 Definition of indirect blood antidoping Identification through laboratory hematological (not toxycological) tests of abnormalities using: POPULATION REFERENCE VALUES (inter-individual differences). A single blood count result (i.e. high hemoglobin or hematocrit) This was the basis for the application in1997 of a threshold to suspend athletes for health reasons INDIVIDUAL REFERENCE VALUE (intraindividual differences). Hematological stability permits the evaluation of unexpected changes in blood results in a single subject: use of longitudinal data or critical difference between measurements. The monitored sequence of results within a structured follow-up program of in and outof-competitions controls (blood profile).

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47 ABP: a differential diagnosis between: 1. true blood doping versus absence of doping 2. altered quality of the blood sample 3. blood changes due to physiological (confounding) factors 4. possible patological conditions

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49 Variability of a test result depends on: 1. «preanalytical» factors related to the subject (biological variability) training, races, disease related to the environment season, climate, temperature altitude related to the blood sample: collection, transport storage 2. analytical variability hemoglobin < 1% reticulocytes..

50 Characteristics of the blood sample blood collection (timing, posture, tourniquet, activity...)

51 Treatment of the blood sample transport, temperature, storage duration

52 Treatment of the blood sample temperature, mixing

53 Blood changes due to physiological not illegal (confounding) factors altitude intermittent hypoxia training/competition coldness emotional stress infections cobalt (?) vegetal drugs...

54 Altitude

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56 Effect of racing

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58 Blood doping scenario

59 Blood doping scenario

60 Possible patological conditions (the Athlete s justification phase) Hemorrhoids Gastric bleeding Menstruation, spontaneous abortion Surgery and hemorrhages Bone fractures, hematomes Dental extractions Viral, bacterial and parasitic infections Unexplained macrocytosis Red cell membrane abnormalities (spherocytosis, stomatocytosis, xerocytosis ).

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