Experimental Animal Model s in Respiratory Diseases

1. Experimental Animal Modelsin Respiratory Diseases Dr. Sibel Atış

2. Experimental Animal Modelsin Respiratory Diseases Why are men such rat?

3. Observation of functional and structural changes • Ethiopathogenesis • Defining of inflammatory processes • Observation of changes in airway behaviours • Assessment of a new molecul effects • Development of a treatment strategy In Respiratory Diseases;

4. Animal model selection Challenge system

5. Animal Model - Selection Criteria • Species • Pathogenesis • Endpoints of study • Manipulations required • Cost • Challenge System • Delivery of Agent • Challenge Dose • Strain or Form of Agent

6. Species • Pathogenesis • Endpoints of study • Manipulations required • Cost • Selection Criteria:

7. Selection of the Species - Sensitivity to Agent • Pathogenesis • Endpoints of study • Manipulations required • Cost

9. Selection of the Species • Pathogenesis -Similarity to Human Disease Process • Endpoints of study • Manipulations required • Cost

10. Asthma animal models: • Antigen induced asthma animal models; • Bronchial hyperreactivity, • Airway eosinophilic inflamation, • mukus hipersecretion, • high IgE levels

11. Asthma animal models: • In mouse models: additionally, active Th2 cell or dendritic cell infiltration

12. Asthma animal models: Spontanous asthma animal models: • “t bet” Knockout mice:

13. Allergic asthma protocolsin C57BL/6 and BALB/c mice

14. Asthma animal models: • Occupational asthma models: • Toluene diisocyanate • Trimellitic anhydride (TMA), respiratory sensitization, • 1-chloro-2,4- dinitrobenzene (DNCB), dermal sensitization, (Vanoirbeek JAJ, et al, J Allergy Clin Immunol 2006)

15. COPD animal models: • Methods: 1) Elastase or exogenous agents (chemicals/particuls) induced 2) Cigarette smoke induced 3) Genetic intervention

16. COPD animal models : • Produced by elastase or exogenous agents: • Porcine pancreatic elastase (PPE), papain and human neutrophil elastase:panasinary emphysema - secretory cell metaplasi, - pulmonary function impairment, - hipoxemia, - right ventricular hypertrophy

17. COPD animal models : Egzogen agents: • repeated endotoxin: neutrophil and active macrophage • Oxidants (Nitrogen dioxide): lung damage • Repeated nitrogen dioxide: focal emphysema • Osone: fibrosis • Cadmium chloride: emphysemawith primary fibrosis • Coul dust and silica: focal emphysema

18. COPD animal models : • Cigarette smoke induced COPD • Best COPD models in animals • Emphysema,small airway lesions and secretory cell metaplasi like as in humans • Similarities or differences between human and animals about cytokine profile, cell proliferation and apopitosis are little known.

20. COPD animal models : Important point in Cigarette smoke induced COPD models • need to time for emphysema lesions: It chages acording to; • Animal to animals • Exposure dose • Exposure methods (nasal or whole body) Min. 4 mounths (in some species 12 mounths ) b)Animal species • Dog: perfect emphysema • Guina pig: vasculary changes • Rat models: do not show this changes

21. COPD animal models : • Produced by Genetic intervention: - Knockout mice - Transgenic mice

22. Lung cancer models: Best models in mouse: 1) spontouneus models 2) produced by full carcinogens 3) produced by Cigarette smoke 4) Transgenic and Knockout models

23. Lung cancer models : • Morphologic, histopatholojic and molecular characteristics like as human adenocancer. • Models of nonsmall cell CA shows not metastase. • Models of small cell CA shows a lot of characteristics of human cancer (including metastase)

24. Lung cancer models : • The important point for clinical applications of this models: Need to be determine of their radiosensitivity and chemosensitivity

25. Tuberculosis models: • Robert Koch showed that M. tuberculosis inoculation induced lesions like human disease. • Infection has been determined with M. tuberculosis cultures in a variety of animals. • Pathological reactions: Different pattern in different animals. • Rabbit / Pulmonary Tubercles • Mouse and Guinea Pig Usually Other Forms

26. Tuberculosis Pathogenesis in animals

27. Pneumonia models: • Bacterial pneumonia models: • S. pneumoniae, • K. pneumoniae, • P. Aeruginosa induced pneumonia • Bacterial pneumonia 1)Intratracheal 2) Directly nasal route (pulmonary infection rate ~ %100) 3) Whole body: aerosol exposure to bacteria

28. Pneumonia models: • Viral pneumonia models: • Any animal model shows not fully clinical disease spectrum of human viral pneumonia (e.g. RSV ).

29. Interstitial pneumonitis/fibrosis models: • Any animal model shows not fully clinical characteristics or histopathology of human disease • Models result in general fibrosis in lung paranchima

30. İnterstitial pneumonitis/fibrosis models: • Pulmonary fibrosis models can be produced by several exogenous agents in several animal species. • Pulmonary fibrosis models produced by Bleomycine has been mostly used.

31. Pulmonay Fibrosis – Animal Models

32. Selection of the Species • Pathogenesis • Endpoints of study • Manipulations required • Cost

33. Endpoints of study: • Survival / mortality • Pathogenesis/pathology • ClininicalObservation - Pneumonia - Respiratory and/or other symptoms (e.g. fever) • Clinical Biochemia (e.g. inflamation mediators) • Bacteriemia / Viremia • Functional / physiological assessment • Efficiency of a new molecul/ treatment agent • Vaccine efficiency

34. Selection of the Species • Pathogenesis • Endpoints of study • Manipulations required • Cost

35. Manipulations required: • Radiography • Larger Animal Model • Diagnostic procedures • Bronchoscopy, BAL,pulmonary catetherisation • Physiological Monitoring • Pulmonary function, electrophysiology • Exposure • Inhalation (Head-Only, Nose-Only, Whole-Body) • Others (Parenteral, Oral, intraperitoneal)

36. Selection of the Species • Pathogenesis • Endpoints of study • Manipulations required • Cost

37. Animal cost: • Rarely Unlimited Funds • Statistical Assessment Cannot Be Compromised • Cost Comparison • Monkeys ~ $3,500-$5,000 • Rabbits ~ $90-$100 • Guinea Pigs ~ $45-$55 • Rats ~ $25 • Mice ~ $5 • Genotypically Specialized Animals - Much More Expensive

38. Challenge system: • Challenge Dose • Delivery of Agent • IM, SQ, Oral, Nasal, Aerosol • Strain or Form of Agent • Different Infectivity characteristics and serotypes

39. Ajanın cinsi veya formu (Kullanılan ajanlar) • Sensitize edici ajanlar (antijenler, allerjenler v.s) • Gazlar; ozon, NO2, SO2 vb • Partiküller; PM, çevresel partiküller, karbon, DEP, nanopartiküller, asbest partikülleri vs • Sigara dumanı, ürünleri • Diğer toksik ajanlar • Mikrobiyal ajanlar • Lipopolisakkarit (selektif pulmoner nötrofiliye yolaçar) • Çeşitli kanserojenler

40. Route of agent delivery

41. Animal Exposures Units For one animal For several animals

42. CONCLUSIONS • Solunum sistemi hastalıklarında; etyopatogenez ve yeni bir tedavi ajanının etkileri başta olmak üzere daha birçok özellik hakkında detaylı bir değerlendirme imkanı verdiği için in vivo hayvan modellerine gereksinim vardır. • Solunum sistemi hastalığı ile ilgili deneysel bir hayvan modeli oluştururken, bu modelin insanlardaki kliniğe en iyi şekilde uyarlanabilmesi açısından hayvan modelinin seçimi ve model oluşturmada seçilecek ajan oldukça önemlidir.

43. CONCLUSIONS • Hayvan modellerinin bir takım kısıtlılıklarının da olduğu unutulmamalıdır. • Spontan olarak solunumsal hastalık gelişen model oldukça azdır. • Hayvan modelleri ister istemez solunum sistemi hastalığının tam fenotipik özelliklerini göstermez. • Her bir hayvan türünün kendine göre zayıf ve güçlü yanları olup, araştırıcı bunlar arasından test edeceği hipotez açısından en uygun modeli seçebilmelidir.

45. Questions ???? Thank you… Doç.Dr. Sibel ATIŞ