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Sandro Rusconi (9.3.52) Lausanne 21.09.2005 AISTS 'genes and sport' 1972-75 School teacher (Locarno, Switzerland) 1975-79 Graduation in Biology UNI Zuerich, Switzerland 1979-82 PhD curriculum UNI Zuerich, molecular biology 1982-84 Research assistant UNI Zuerich 1984-86 Postdoc UCSF, K Yamamoto, (San Francisco) 1987-93 Principal Investigator, UNI Zuerich, PD 1994-today Professor Biochemistry UNI Fribourg 1996-2002 Director Swiss National Research Program 37 'Somatic Gene Therapy' 2002-03 Sabbatical, Tufts Med. School Boston and Univ. Milano, Pharmacology Department 2002-05 President Union of Swiss Societies for Experimental Biology (USGEB) 2002-06 Euregenethy Network (EU-harmonsiation of biosafety and ethical aspects in gene therapy) 2005-xx Director of Governmental Division for Culture and University Affairs of Canton Ticino UNIFR Rusconi 2005 'Gene doping': Is it coming? Is it there? UNIFR Rusconi Issues that will be addressed 2005 What is a 'gene'? 1 gene -> several fiunctions, genes language, gene expression, gene manipulation What is therapeutic gene transfer (gene therapy)? functions transfer, objectiives, somatic How far has gene therapy progressed ? principles, goals, obstacles, clinical achievements Which possibilities exist gor Gene-based Doping ? doping in general, gene doping perspectives, obstacles, detectability, side effects, risk-benefits Conclusions technically too early but recklessness and money make it moving anyway Quintessence read it in this orange box Doping in top sports has some deadly aspects... Name Sport Age Date Cause Denis Zanette (Ita) Fabrice Salanson (Fra) Vivien Foe (Cam) Jose Maria Jimenez(Spa) Miklos Feher (Hun) Raymond Junikis Johan Sermon Marco Pantani ??? cyclist cyclist football ciclist football basket cyclist cyclist ... 33 23 28 32 24 23 21 28 ... 10.01.2003 03.06.2003 26.06.2003 8.12.2003 25.01.2004 10.02.2004 13.02.1004 14,02.2004 ... cardiac arrest dentist room cardiac arrest hotel room cardiac arrest on the field cardiac arrest hospital cardiac arrest on the field cardiac arrest at the match cardiac arrest at home cardiac arrest hotel room ... Questions what is the perception of risk/benefit in sports? Can all this worsen when gene transfer enters the scene? UNIFR Rusconi 2005 Mythos 'Gene': in the good and in the bad ... UNIFR Rusconi 2005 Medicine Neue Medikamente, neue Heilungschancen, neue Diagostik, ... Myths 'Gene therapy': - against hereditaryMedicine diseases Bio-Waffen, Monster-Generation, - transmissible modification Designer-babies, ... Agriculture Neue Eigenschaften von Nutzpflanzen/ Myths 'Gene doping': Nutztieren ... - better than conventional - hereditary geneticAgriculture modification Oekologische Katastrophen, - pre-natal designerGesundheitspropleme, athletes «GMO=Giftig» Ergo: we must first eliminate these myths UNIFR Rusconi 1013 1 Organism -> Cells, distributed in specialised organs and tissues 2 mm 2m 2005 0.2mm 0.02mm 0.001mm DNA RNA Protein Ergo at each cell division the genetic marterial is copied in 1 cm3 -> 1'000'000'000 cells The old motto: 'one gene one function' is obsolete... UNIFR Rusconi 2005 DNA RNA(s) Protein(s) Transcription / translation Gene expression GENE 100 ’000 genes (50 ’000 genes?) Ergo: 2-5 FUNCTIONS side effects in gene transfer might be caused also by supplementary and yet undiscovered functions of a given gene >300 ’000 functions (>150 ’000 functions) But ...what is actually 'a gene'?: ...a regulated nano-machine for the production of RNA DNA GENE RNA Protein Therefore, to fullfil its FUNCTION role, Transcription / translation a transferred gene segment must include: regulatory sequences for Transcription proper signals for RNA Maturation/transport proper signals for mRNA Translation proper signals for mRNA Degradation RNA DNA spacer regulatory coding spacer UNIFR Rusconi 2005 The reductionist Paradigm of molecular biologists UNIFR Rusconi 2005 DNA GENE GENE OK Protein Gene transfer can imply: FUNCTION(s) Transfer of a new Function, or Transfer of a compensatory F., or Transfer einer interfering FUNCTION OK Function GENE KO FUNCTION KO GENE transfer FUNCTION transfer Gene transfer as logical consequence: the third era of molecular biology Eighties Genes as probes Nineties Genes as factories Y2K Genes as drugs 1 2 3 4 5 ok ** ok ** ** 50 3000 10 80 85 90 95 99 1000 80 85 90 95 00 Gene transfer (Gene therapy): logical consequence of development in molecular biology UNIFR Rusconi 2005 Somatic Gene therapy (SGT) Definition and applications 2005 Chronic treatment Definition of SGT: 'Use genes as drugs': Correcting disorders by somatic gene transfer NFP37 somatic gene therapy www.unifr.ch/nfp37 UNIFR Rusconi Acute treatment Preventive treatment Hereditary disorders Acquired disorders Loss-of-function Gain-of-function Pharmacological considerations, differences with conventional medication therapy Classical Drugs Mw 50- 500 Daltons Synthetically prepared Rapid diffusion/action Oral delivery possible Cellular delivery: - act at cell surface - permeate cell membrane - imported through channels Can be delivered as soluble molecules Ångstrom/nm size rapidly reversible treatment Protein Drugs Mw 20 ’000- 100 ’000 Da Biologically prepared Slower diffusion/action Oral delivery not possible Cellular delivery: - act extracellularly 2005 Nucleic Acids Mw N x 1’000’000 Da Biologically prepared Slow diffusion Oral delivery inconceivable Cellular delivery: - no membrane translocation - no nuclear translocation - no biological import Can be delivered as Must be delivered as soluble molecules complex carrier particles nm size 50-200 nm size rapidly reversible treatment slowly or not reversible Theray with nucleic acids (DNA) UNIFR Rusconi Need special formulation (vectors) more complex less reversible Why 'somatic'? UNIFR UNIFR Rusconi Rusconi 2005 2003 Germ Line Cells: the cells (and their precursors) that upon fertilisation can give rise to a descendant organism Ergo: somatic gene transfer is NOT aiming at GERM LINE cells Somatic Cells: all the The other cells of the body is therefore modification NOT HERITABLE UNIFR UNIFR Rusconi Rusconi The four technical basic questions in SGT 2005 2003 Efficiency of gene transfer Specificity of gene transfer Persistence of gene transfer Toxicity of gene transfer The variables which disease? which gene? which vector? which target organ? which type of delivery? Remember! UNIFR Rusconi Three anatomical delivery methods in SGT: 2005 Ex-vivo In-vivo topical delivery Ergo In-vivo systemic delivery ex vivo or local delivery are currently preferred over systemic delivery V Examples: - bone marrow - liver cells - skin cells Examples: - brain - muscle - eye - joints - tumors Examples: - intravenous - intra-arterial - intra-peritoneal Two classes of vectors: viral / non viral Transfert non viral (transfection) UNIFR Rusconi 2004 A Why are viruses 'better'? viral transfer (Infection) direct nuclear shuttling! viral transfer is much more efficient nonviral transfer must solve a B number of hurdles - serum protection/stability - target docking Nuclear envelope barrier! - endosomal escape - nuclear trafficking - genomic integration - anti apoptotic functions - immunological camouflage - ... Example: transfection (non viral) versus Infection (viral) transfer of a reporter gene UNIFR Rusconi 2005 Transfection cells exposed to 1'000'000 particles/cell 12 hours Infection cells exposed to 3 particle/cell 30 min Ergo virally mediated gene transfer is millions of times more efficent than nonviral transfer (when calculated in terms of transfer/particle) Mini- List von current gene transfer methods UNIFR Rusconi 2005 r-Adenovirus Naked DNA r- Adeno-associated V. Liposomes & Co. r- Retrovirus Oligonucleotides r- Lentivirus Recap: Limitations of current vectors r-Adenovirus - no persistence - limited packaging - toxicity, immunogenicity r-AAV - no integration in host g. - very limited packaging - autoimmunity? r-Retrovirus (incl. HIV) - limited packaging - random insertion - unstable genome General - antibody response - limited packaging - gene silencing - Manufacturing limitations Solutions: - synthetic viruses (“Virosomes”) UNIFR Rusconi 2005 Biolistic bombardment or local direct injection - limited area Electroporation - limited organ access Liposomes, gene correction & Co. - rather inefficient transfer General - low transfer efficiency - no or little genomic integration Ergo Solutions: see an increasing the future will probably - improved liposomes interest in viral-like, but artificial particles with viral properties (“Virosomes”) The traditional clinical path: lots of time/money UNIFR Rusconi 2005 year event costs U$D 0 Idea 0 2 Cell culture assays 0.5 Mio 5 Pre-clinical tests animal models 2 Mio 7 10 15 16>> Clinical phase I 5-20 patients verify side effects 6 Mio Clinical phase II 30-100 patients dosis escalation 12 Mio Clinical Phase III >300- 1000 patients multicentric double blind 80 Mio Registration / Availability Fazit: on average only 1out of 5 drugs makes it to approval -> 500 Mio U$D investment per successful drug !!! Gene therapy in the clinics: Trials Worldwide (cumulative) trials 80 60 40 Rusconi 2005 patients Ergo 100 UNIFR in spite of 13 year- research only less than 2% of the trials has reached phase III not necessarily due to the «novel» 'fail early, fail fast'cancer paradigm As of January 2005: 938 cumulative protocols (90-2005) 1500 4700 treated /enrolled patients ! As of Jan 1, 2004: 1 approved product in China (Gendicine, by Sibiono Inc. 2004) hered. 2600 Patients treated in 2004 66% phase I 19% phase I-II 13% phase II 0.8% phase II-III 1.7% phase III II 1000 I-II I 500 vasc. 20% overall still pending Infect. or not yet Initiated ! 20 www.wiley.com/genetherapy 1990 1992 1994 1996 1998 2000 clinical milestones in gene therapy UNIFR Rusconi 2005 1990, 1993, 2000, // ADA deficiency F Anderson, M Blaese 90/93/ C Bordignon 2000/2004 Anderson, 1990 Isner, 1998 Fischer, Kirn, 2000 1997, 2000, Critical limb ischemia 2000, 2002 J Isner († 4.11.2001), I Baumgartner, 1998 25 lives 2001 Manuel Grez were so far documentedly saved by GT in 2002 Sibiono Hans Peter Hossle 2000, Hemophilia european trials (x-SCID, ADA, CGD) 2003 Shenzen Reinhard Seger M Kay, K High (France, UK, Italy) (all in phase I) Intravascular adenoviral 2004/2005agents 2000, 2002, X-SCID in cancer patients: ~200 lives quality-improved A Fischer, 2000/2002, Thrasher 2003 Lessons from clinical very encouraging data trials from in several other phase I and II trials just initiated(review) clinical trial, dropped inpatients 2004? 2001, 2003 ONYX oncolytic Viruses prospected >10 ~nnn lives saved or quality-improved ? licensed China 2005? D Kirn (Cancer Gene Ther 9, p 979-86) commercialisation of by Gendicine (50'000 patients prospected Bordignon, 2000Approved (ESGT, Stockholm) Gendicine (Jan 2004) for cancer for 2006) 2002, science 296, 2410 ff) 2004, Chronic Granulomatous Disease M Grez Frankfurt; R Seger Zürich 2004/2005 Gendicine (adeno-p53 vector) L Peng, Sibiono Inc, Shenzen, China treatment in China. -> ! Hum Gene Ther 16, 1016 ff. Die most feared side effects of Gene Therapy UNIFR Rusconi 2005 Immune response to vector immune response or long term side effects from new or foreign gene product (-> autoimmunity) General toxicity of viral vectors Adventitious contaminants in recombinant viruses Random integration in genome -> insertional mutagenesis (-> cancer risk) Contamination of germ line cells Ergo «The more effective is a drug, the more side effects it will generate». Side-effect-free illusion in the 90ties is over Primitive state of the vectorology/delivery UNIFR SAEs1: from Pennsylvania to Paris Rusconi 2005 NY May 5, 1995, R. Crystal: adenovirus, cystic fibrosis (lung) one patient mild pneumonia-like condition Trial interrupted and many others on hold. Most Recent Paris' Trial News discussed under: www.unifr.ch/nfp37/adverse03.html UPenn, Sept. 19, 1999, J. Wilson: adenovirus , OTC deficiency (liver) one patient (Jesse Gelsinger) died of a severe septic shock. Many trials were put on hold for several months (years). Paris, Oct 2, 2002, A Fischer: retrovirus , x-SCID (bone marrow) one patient developed a leukemia-like condition. Trial suspended and some trials in US and Germany on hold until 2003. Paris, Jan 14, 2003, A Fischer: retrovirus X-SCID (bone marrow) same cohort a second patient developed a similar leukemia 30 trials in USA were temporarily suspended Ergo gene therapy can produce both shortterm and long-term severe side effects through acute immunogenicity or insertional mutagenesis (cancer risk) SAEs2: Recent Autoimmunity Reports in gene transfer... should open the eyes of potential dopers UNIFR Rusconi 2005 Blood (2004), Vol. 103, No. 9, comment: pp. 3248-3249 Autoimmunity in EPO gene transfer (macaques) Els Verhoeyen and François-Loïc Cosset Papers: - Chenuaud and colleagues (page 3303) - Gao and colleagues (page 3300) inadvertent autoimmune response in nonhuman primates resulting from transfer of a gene encoding a self-antigen. - homologous EPO cDNA via AAV vectors - muscle or lung, - supra-physiologic serum levels of EPO Ergo K High, ASGT June meeting 2004 somatic gene transfer and ectopic transgene expression is detectable and can generate mid-term auto- immunity sounds quite risky for Epo doping [Abstract1002] Immune Responses to AAV and to Factor IX in a Phase I Study of AAV-Mediated, Liver-Directed Gene Transfer for Hemophilia B Now, lets dedicate completely to gene doping: .. is ist thinkable? Gene therapy (features summary) - treatment not hereditary - principle works - not yet clinically established - high risk with todays vectorology - applicable to virtually all disease status - pioneer status Ergo: Realistically speaking, efforts in SGT should be currently restricted to severe diseases, and we should close the talk here, however... UNIFR Rusconi 2005 UNIFR The three levels of Doping... Rusconi 2005 + Before the competition (anabolic enhancers) 'Molecular treatments Application of the know-how in molecular genetics to doping + During the competition (performance enhancers) + After the competition (repair enhancers) Which gene-transfer-Strategies could be concretely conceivable for doping? UNIFR Rusconi 2005 ex vivo, hematopoietic tissue: pro hematopoietic (Epo receptor, oxygen transport...) in vivo local (example muscle): metabolic enhancers, growth factors, muscular fiber changers, cardio-modulators (glucose/oxygen, MGF, IGF-1, anti-myostatin, Epo) in vivo local (example joints): Ergo: pain reducers, inflammation inhibitors, recovery Doping and with gene transfer is repair factors (anti-TNF, BMPs, ...) conceivable at many different levels in vivo systemic: anabolic enhancers, endocrine factors, pain killers, vascular controllers, (hormone metabolising enzymes, proenkephalins, ...) The experiments of Lee Sweeney (2004) have raised further smoke... UNIFR Rusconi 2005 Gene transfer of IGF-1 (J. App Physiol 96, 1097 ff (2004)) The features IGF-1 -> growth factor for muscles AAV Vector, intra muscular Rat model , + or - training Results muscle force and muscle mass increased beyond levels obtained in training Ergo ok, Dr. Sweeney, transfer of IGF-1 in rats significantly increases muscle performance,, but... muscle force questions - can it be extrapolated to humans? - kg muscle to tranduce ? - how to manufacture sufficient vector? - symmetry of effects? training: + - adverse side+effects? IGF-1: - - - + + Which side effects should we expect if gene transfer would be currently applied in doping UNIFR Rusconi 2005 Short -mid term Autoimmunity Hyperimmunity Toxic shock Long term Specially dangerous: Recklessness... Fibrosis Improper technology Cancer (unsuitable vector, low competence of doctors) conventional side- effects of Improper Material administered factors (contaminated with pathogens or pyrogens) Inaccessibility to future gene Insufficient follow-up therapy interventions (immunity to vectors) Which would be the objective limitations of gene doping? UNIFR Rusconi 2005 Viral gene transfer Ergo: immune problems risks seem today currently limited readministration possibilities higher than benefits general toxicity, genotoxicity Nonviral gene transfer generally inefficient lack of persistence, requires readministration Strategy-independent problems laborious, not readily available long term gene expression difficult to control irreversible effects or permanent tagging asymmetry of effects N R Detection possibilities of gene doping UNIFR Rusconi 2005 Antibody detection (viral antigens) r-nucleic acids detection (PCR) recombinant protein / post-translational modification detection (MALDI-TOF ) Anatomically difficult to detect Ergo (if locally administered) foreign genes detectable only short-> but leaves permanent genetic marking term in blood or body fluids, but - foreign genes detectable long term Detection of nucleic acids cannot be performed body fluids in tissueinbiopsies, and (except in early phase after systemic administration) - abnormal gene products detectable -> might require specific tissue biopsy (example GT erythropoietin in monkeys) Comparison of advantages/disadvantages: with respect to conventional Doping Category Ergo: Drug/protein Gene-based the odds would speak actually against Gene doping Rapidity of effects rapid slow but: Reversibility rapid slow awareness of the above needs common sense, a property that is rare in the doping field Dosage straightforward difficult and: of treatm. simple Complexity complex ...there are several borderline sports lacking doping control Associated risks Question: depends high ...isnt it the high publicity over gene doping just a sort of psychologically intimidating some nations (this has Concealability possiblestrategy by difficult /impossible happened before in doping) UNIFR Rusconi 2005 Doping with Gene transfer: Proust's questionnaire UNIFR Rusconi 2005 Is someone in the field currently 'thinking GT' for doping ? yes Which sports will produce the first case ? horse racing? Which country may produce the first human cases? ...China? Will gene doping be more effective than conventional? QuickTime™ et un décompresseur None sont requis pour visualiser cette image. No Shall it be effective at all ? probably little Will some athlete suffer or even die from GT attempts? yes Which gene will be first transferred for doping purposes ? Epo Shall gene doping remain difficult to detect ? No Why is then gene doping still so attractive ? M Proust 1871-1922 ignorance ... Thank you, and let's hope that sports can continue producing genuine emotions and fairplay AISTS, Prof. Bengt Kayser my collaborators at UNIFR for correspondence: [email protected] for info : www.unifr.ch/nfp37 UNIFR Rusconi 2005 «That's all folks» ...looking forward to your questions www.unifr.ch/nfp37 UNIFR Rusconi 2005 UNIFR Rusconi 2002