The Lung as a Model for Translational Medicine

Transcription

1 The Lung as a Model for Translational Medicine Professor Michael P. Keane MD, FRCPI UCD School of Medicine & Medical Science Scoil an Leighis agus Eolaíocht An Leighis UCD

2 Translational Medicine Interaction between basic research and patient care Traditionally basic research has been separated from clinical practice Many pharmaceutical companies now building translational medicine groups Bench to bedside

3 A report in 1838 on cirrhosis of the lung..."as contracting fibres... tend to draw in the tissue of the lung, obliterating its small air tubes and its blood vessels, the large bronchial tubes dilate... until at last the tissue of the lung, diminished to a very small size, presents but a dense fibro-cellular tissue Corrigan DJ. On cirrhosis of the lung. Dublin J Med Sci 1838;13:

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5 Current Definition of IPF Distinct chronic fibrosing interstitial pneumonia Unknown cause Limited to the lungs Has typical HRCT findings Associated with a histologic pattern of UIP ATS/ERS Consensus Statement. Am J Respir Crit Care Med. 2002;165:

6 Classic IPF HRCT Basal and subpleural predominance Reticular opacities Traction bronchiectasis Image courtesy of W. Richard Webb, MD. Honeycombing

7 Advanced IPF HRCT Extensive honeycombing Traction bronchiectasis Reticular opacities Basal and subpleural predominance Image courtesy of W. Richard Webb, MD.

8 Combined Corticosteroid and Cyclophosphamide Treatment Does Not Improve Survival in IPF Patients 1.00 Probability of Survival Expected P = 0.58 Untreated (n = 82) Median survival = 1431 days Treated (n = 82) Median survival = 1665 days Days of Follow Up No evidence that corticosteroid plus cyclophosphamide treatment improves survival Most patients do not respond to immunosuppressive agents Collard HR, et al. Chest. 2004;125: Walter N, et al. Proc Am Thorac Soc. 2006;3:

9 Evolving Model of Pathogenesis: Aberrant Response to Persistent Injury Epithelial cells Cell death impaired reepithelialization Basement Membrane Damage Myofibroblast Cell survival resistance to apoptosis Growth factors and other products of epithelial cell injury Oxidative Stress Procoagulant Activity T H 2-T H 1 Balance Collagen matrix remodeling Vascular Remodeling Courtesy of Paul W. Noble, MD, and Victor J. Thannickal, MD.

10 Microvascular changes UCD School of Medicine & Medical Science Scoil an Leighis agus Eolaíocht An Leighis UCD

11 Tumor Growth Pulmonary Fibrosis Angiogenesis Embryonic Development Coronary Artery Disease Psoriasis Rheumatoid Arthritis

12 INTRODUCTION Vascular Remodeling associated with IPF first described by Turner-Warwick Turner-Warwick Thorax 1963; 18:225 Evidence of vascular remodeling in rat model of bleomycin induced pulmonary fibrosis Peao et al Anat Rec 1994; 238:57

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14 IPF Normal

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16 ELR + CXC Chemokine Angiogenic Activity Control IL-8 ENA-78 GRO-α GCP2

17 Vascular Remodeling in UIP/IPF Control Factor VIII-related antigen

18 LUNG TISSUE IL-8/IP-10 LUNG TISSUE IL-8 LUNG TISSUE IP * 6 1 (ng/ml) 4 2 * (ng/ml) IPF Control 0 IPF Control

19 Lung Tissue Angiogenic Activity CTRL Lung Homogenate IPF Lung Homogenate CTRL + Anti IL-8 IPF + Anti IL-8 CTRL + Anti IP-10 IPF + Anti IP-10

20 Animal Model Neutralization of the angiogenic chemokine MIP-2, attenuates pulmonary fibrosis Keane et al J Immunol 1999; 162:5511 Administration of the angiostatic IFN inducible chemokines, CXCL10 and CXCL11, attenuates pulmonary fibrosis Keane et al J Immunol 1999; 163:5686 Burdick et al Am J Respir Crit Care Med 2005;171(3):261-8

21 Control IP-10 Inhibits Bleomycin-Induced Pulmonary Fibrosis IP-10

22 Cosgrove et al Am J Respir Crit Care Med 2004;170:242

23 Interferon γ-1b - GIPF-001 Trial Classification Mechanisms Trial Design Inclusion Criteria Primary Endpoint Treatment Arms Pleiotropic biologic response modifier Antifibrotic, angiostatic, antiinfective, antiproliferative Multicenter, double blind, placebo controlled Age years, with symptoms of IPF for 3 years Composite: progression-free survival 200 µg TIW vs placebo Number of Patients 330 Treatment Duration Result 48 weeks Endpoints not met; new trial design based on positive survival trend Raghu G, et al. N Engl J Med. 2004;350:

24 GIPF-001 Study Results Survival 1 Lung Function (FVC) Probability of Survival IFN γ-1b Placebo P = Day Week N = Raghu G, et al. N Engl J Med. 2004;350: Data on file with InterMune.

25 Interferon γ-1b INSPIRE Trial Classification Mechanism Trial Design Inclusion Criteria Primary Endpoint Treatment Arms Number of Patients Treatment Duration Result Pleiotropic immunomodulatory cytokine Antifibrotic, angiostatic, antiinfective, antiproliferative Multinational, randomized, placebo controlled Age years, FVC 55%, and DL CO 35% of predicted Survival time 200 µg TIW vs placebo, 2:1 randomization 826 (enrollment complete) 2 years from date of 600th patient enrollment Discontinued due to lack of efficacy Accessed March 2007.

26 Bone marrow derived cells UCD School of Medicine & Medical Science Scoil an Leighis agus Eolaíocht An Leighis UCD

27 Origin of Fibroblasts Fibroblasts first described by Cohnheim in 1867 Resident embryonic mesenchymal cells persisting form organogenesis Fibroblasts emerge from the bone marrow Fibroblasts derive locally from EMT

28 Fibrocytes Fibroblasts and myofibroblasts have a pivotal role in the generation of ECM Fibrocytes are blood-borne fibroblast-like cells Fybrocytes express type I collagen, CD34 and CD45 and in culture spontaneously express α SMA Markers associated with human fibrocytes.

29 CXCR4 and CXCL12 Important role in leukocyte homing and tumor metastasis. CXCR4 binds a single ligand: CXCL12. Deletion of both CXCR4 and CXCL12 lethal during embryogenesis. CXCR4 is expressed on the surface of circulating fibrocytes.

30 CD45 + Col I + CXCR4 + FIBROCYTES MIGRATE TO LUNGS OF SCID MICE A B CD45 Positive Cells Control Collagen I Collagen I CXCR C CXCR4 α-sma D Fibrocytes per h.p.f *P < 0.05 * * CXCL12 (ng/ml) Human CD45 + Col I + CXCR4 + Cells/Lungs (x10 5 ) Bleo * *P < 0.05 Saline

31 A CD45 + Col I + CXCR4 + Cells/Lungs (x10 6 ) Control Ab Neutralizing anti-cxcl12 Antibodies Block Intrapulmonary Fibrocyte Recruitment and Collagen Deposition * Anti-CXCL12 * P < 0.05 NS Saline Naive B Collagen (µg/lungs) Control Ab * * Anti-CXCL12 * P < 0.05 Saline Naive C 3.5 Cells/Lungs (x10 7 ) Control Ab Anti-CXCL12 0 CD3 CD4 CD8 NK1.1 Ly6 Mac

32 Neutralizing anti-cxcl12 antibodies decrease Pulmonary fibrosis in bleomycin-treated mice A B 20,000 Bleo + Control Ab Picrosirius Red Staining (Square pixels; HPF 400x) 16,000 12,000 8,000 4,000 0 Control Ab * P < * Anti-CXCL12 Bleomycin Bleo + Anti-CXCL12

33 Conclusion Circulating CD45 + Col I + CXCR4 + fibrocytes contribute to the development of pulmonary fibrosis Phillips et al J Clin Invest 2004

34 CXCL12-CXCR4 Axis is Important in Fibrocyte Extravasation in Pulmonary Fibrosis Strieter RM, et al. J Clin Invest 2007; 117:

35 Bone Marrow Derived Cells and Fibrosis Bone marrow derived cells appear in the lung following bleomycin administration Express Type I collagen but not alpha smooth muscle actin Hashimoto N et al J Clin Invest 2004;113: 180

36 Mesenchymal Stem Cells in the Lung MSC engraft in the lung following bleomycin injury (Type II cells) Early MSC administration attenuates inflammation and the fibrotic response to bleomycin Ortiz et al PNAS 2003;100:8407

37 MSC and Repair Myelosuppression increases susceptibility to lung injury following bleomycin Administration of MSC could attenuate injury Protection involves suppression of inflammation and production of reparative growth factors Rojas et al Am J Resp Cell and Mol Med 2005;33:145

38 TGF-β Final common path in many models of fibrosis Over expression leads to fibrosis Transient expression of IL-1 leads to inflammation and TGF-β mediated fibrosis (via Smad3) Promotes a-sma expression in fibroblasts Promotes EMT Bonniaud et al J Immunol 2005;175:5390

39 Implications for Therapy Cell based therapy? Inhibition of mobilization from the bone marrow CXCR4 antagonists (AMD3465) Inhibition of fibrocyte differentiation Endothelin? TGF-β?

40 Pirfenidone - CAPACITY 1 & 2 Trials Classification Mechanism Trial Design Inclusion Criteria Efficacy Endpoints Treatment Arms Number of Patients Treatment Duration TGFβ inhibitor Antifibrotic Randomized, double blind, placebo controlled Age years, confident IPF diagnosis FVC 50% predicted value, DL CO 35% predicted value Primary: Mean change from baseline in % predicted FVC Secondary: Changes in symptoms, functional capacity, QOL CAPACITY 1: PFD 2403 mg/d vs placebo CAPACITY 2: PFD 1197 mg/d vs PFD 2403 mg/d vs placebo CAPACITY 1: 320 CAPACITY 2: weeks Accessed March 2007.

41 Bosentan BUILD 3 Trial Classification Mechanisms Trial Design Inclusion Criteria Primary Endpoint Endothelin-1 receptor antagonist (ERA) Vasodilator, possible antifibrotic Event driven, international, double blind, randomized [2:1 (bosentan:placebo)] Proven IPF diagnosis < 3 years, with SLB Time to disease worsening (FVC and DL CO ), acute exacerbation or death Number of Patients 390 Treatment Duration Results 131 events Recruitment pending Accessed March 2007.

42 ARDS

43 NIH Multi-Centered Trial Low Tidal Volumes in ARDS 10 university centers in NIH ARDS-Network 861 patients randomized to traditional versus low tidal volume ventilation Qualifications: PaO 2 /FiO 2 <300 bilateral diffuse infiltrates No evidence of left heart failure Detailed ventilator management protocol ARDS-Net. NEJM 2000; 342

44 ARDS network Ideal body weight Volume assist/control until weaning Adjust Vt in steps of 1ml/kg every 1-2 hours until 6ml/kg If Pplat >30cm, decrease Vt to 5 or 4 ml/kg If Pplat <25cm and Vt < 6ml/kg, increase by 1ml/kg

45 Main Outcomes Parameter: Traditional: Experimental: P value Death 39.8% 31.0% Weaned by day % 65.7% <0.001 Barotrauma 11% 10% 0.43 # days without other organ failure 12 ± ± ARDS-Net. NEJM 2000; 342

46 A * B * * * Ventilator Induced Lung Injury Score * Ratio of Lung:Plasma Evans Blue * Normal Low Peak Pressure/ Stretch High Peak Pressure/ Stretch Normal Low Peak Pressure/ Stretch High Peak Pressure/ Stretch

47 Histopathology of lungs Associated with Mechanical Ventilation Normal Low Peak Pressure/ Stretch High Peak Pressure/ Stretch Six hours post mechanical ventilation

48 Panel I Lung-Derived CXC Chemokines A KC/CXCL1 (ng/ml) * Normal * * Low Peak Pressure/ Stretch High Peak Pressure/ Stretch B MIP-2/CXCL2/3 (ng/ml) Normal * * * Low Peak Pressure/ Stretch High Peak Pressure/ Stretch Panel II A KC/CXCL1 (ng/ml) Normal Low PeakHigh Peak Pressure/ Pressure/ Stretch Stretch Plasma-Derived CXC Chemokines B MIP-2/CXCL2/3 (ng/ml) Normal Low PeakHigh Peak Pressure/ Pressure/ Stretch Stretch

49 Histopathology of lungs Associated with Mechanical Ventilation Panel I Anti-CXCR2 antibody with High Peak Pressure/Stretch Control antibody with High Peak Pressure/Stretch Panel II CXCR2-/- mice with High Peak Pressure/Stretch CXCR2+/+ mice with High Peak Pressure/Stretch Six hours post mechanical ventilation