Disclosures The Lung as a Site of Initiation of Rheumatoid Arthritis-related Autoimmunity No conflicts of interest Kevin Deane, MD/PhD University of Colorado Rheumatoid Arthritis: Where Does it Begin? Monday, November 7, 2011: 2:30 PM-4:00 PM W196b (McCormick Place Convention Center) 1 2 Objectives 1) Review epidemiologic and clinical data that support that RA may be initiated in the lung 2) Review lung anatomy and physiology to understand how the lung may be a site of generation of autoimmunity 3) Discuss necessary steps to prove that the lung is a site of initiation of autoimmunity in RA, with presentation of data from our own studies in this area. 3 Phases of RA Development Phase 1 Phase 2 Phase 3 Environmental Exposures Genetic Circulating Risk RA-related Pre-Clinical Clinical Disease autoimmunity Autoimmunity suggests RA starts outside of the joints Site of origin of RA-related autoimmunity? Joints? Mucosal surfaces? Bone marrow? Other? RATIONALE: 1) Understand the key sites and mechanisms of RA development 2) Stop disease prior to substantial injury (prevention) 4 Inhaled risk factors for RA Epidemiologic and clinical evidence that RA is initiated in the lung Tobacco smoke Klareskog et al 2008 Dust Oliver et al Scan J Rheumatol 2006 Pollution Hart et al Environ Health Perspect 2009 It is possible that these factors lead to initial injury/inflammation and autoimmunity in the lungs 5 6 1
Lung disease and RA-related autoimmunity are present soon after and preceding joint disease Caveats Lung disease is present in early RA Metafratzi et al Scand J Rheumatol 2007; 2011 ACR: Abstract 2179. 4 RF/CCP+ subjects with ILD and no IA at presentation 1 later developed IA classifiable as RA Gizinski et al Clin Rheumatol 2009 74 CCP+ subjects with lung disease and no IA 3 later developed IA classifiable as RA Fischer et al Abstract, ACR Annual Meeting 2010 (submitted) Do inhaled factors initiate autoimmunity in the lung, or do they travel thru the lung to cause organ injury elsewhere? Example: smoking and bladder cancer acrolein from tobacco toxic to the bladder Are inhaled factors permissive for some other factor? Example: smoking allows infection Lung disease preceding joint disease may not mean that RA is initiated in the lungs - the lung may be an early target of circulating RA-related autoimmunity 7 8 Anatomy and physiology of the lung supports that the lung may be a site of generation of autoimmunity Lumenal: IgA, IgG Complement Fibrinogen 9 Holt et al Nat Rev Immunol 2008 10 Immunity in the lung BALT Bronchial Associated Lymphatic Tissue Localized response to infections Generates IgA and other isotypes at mucosal surface -these antibodies can become systemic Reviewed in Randall TD. Adv Immunol 2010 11 12 2
BALT in RA BALT has been demonstrated in patients with RA and clinicallyapparent lung disease Rangel-Moreno et al J Clin Invest 2006 Normal Lung RA Lung Rangel-Moreno et al, J Clin Invest, 2006. 13 14 BALT from patients with RA and lung disease contains RF and ACPA producing B cells Hypothesis: The lung is a site of initiation of RA Environmental factors Inflammatory joint disease /RA Plasma cells (+) for RF Fc portion of human IgG Plasma cells (+) for ACPAs Citrullinated fibrinogen Initial generation of RA-related autoimmunity in the lung due to genetic + environmental interactions Spread of autoimmunity from the lungs to the circulation ( Preclinical RA ) Rangel-Moreno et al J Clin Invest, 2006. 15 16 How to prove that the lung is a site of initiation of RA-related autoimmunity? 1) Demonstrate the generation of RA-related autoimmunity in the lung in absence of and prior to joint disease 2) Identify factors that can drive the initiation of RA-related autoimmunity in the lung 3) Demonstrate mechanisms by-which RA-related autoimmunity may start in the lungs and then move to the joints The lung may not be the site, or the only site, of initial generation of RA-related autoimmunity Oral cavity, gut, GU, etc. -- each of these locations has its own mucosal-associated lymphatic tissue But, proving that other sites are the origin of RA requires similar approaches. 17 18 3
A crucial part of demonstrating that RA starts in the lung (or any other site) is to identify and study individuals that are in the early phases of RA development. Phases of RA Development Phase 1 Phase 2 Phase 3 Environmental Exposures Genetic Risk Pre-Clinical Clinical Disease Autoimmunity 19 20 How do we find individuals to study in real-time that are in the preclinical period of RA development? Studies of the Etiologies of Rheumatoid Arthritis (SERA) Multi-site project based at the Univ of Colorado designed to understand the natural history of RA development through prospective evaluations of individuals at-risk for future RA. PI s: V. Michael Holers, Jill M. Norris Subject enrollment sites: Denver, CO (University of Colorado) Los Angeles, CA (Cedars Sinai) Seattle, WA (Benaroya Institute) Omaha, NE (RAIN Network) Chicago, IL (University of Chicago) New York, NY (North Shore-Long Island) 21 Multiple collaborations 22 First-degree relatives of probands with RA CCP+ subjects without IA identified thru health fair screening DR4-enriched subjects from diabetes studies Overview of SERA prospective study Pool of individuals at-risk for RArelated autoimmunity that can be assessed in real time Subset at very highrisk for future RA indicated by autoantibodies 23 Cardiovascular disease risk in preclinical RA Norris ACR WOR Special Session Cytokine and chemokine elevations in preclinical RA Hughes-Austin Abstract 100 SERA: Individuals at-risk for future RA Immune responses to P ging in preclinical RA Mikuls Abstract 766 Lung studies Demoruelle Abstract 769 Willis Abstract 2821 24 4
SERA: Lung Project Central hypothesis: RA is initiated in the lung Initial aims: 1) Demonstrate non-invasively that inflammatory lung abnormalities are present in preclinical RA 2) Demonstrate production of RA-related autoimmunity within the lung - Established RA - Preclinical RA SERA: Lung Project Inclusion for imaging studies: 1) Select at-risk individuals that are highly likely to be in preclinical phase of RA CCP and/or 2 or more rheumatoid factor isotypes (IgG/A/M) >96% specific for future RA Deane et al Arthritis Rheum 2010 2) No inflammatory arthritis Comparators: Autoantibody negative SERA controls, similar to Ab(+) cases Early seropositive RA Lung Study: High-resolution computed tomography of the lungs to evaluate inflammatory changes Pulmonary function testing 25 26 Airways abnormalities more common in Ab(+) subjects compared to Ab(-) controls Demoruelle MK et al, Abstract 769 Autoantibody (-) Controls (N=15) Autoantibody (+) Cases (N=42) P-value All Subjects 33% (5) 76% (32) 0.005 Never smokers 33% (4/12) 73% (19/26) 0.033 Airways abnormalities = bronchial wall thickening, bronchiectasis, centrilobular opacities (bronchiolitis) and air trapping 3/42 of Ab(+) cases have developed classifiable RA ~12 months after their participation in the lung study 27 Airways abnormalities are similar in Ab(+) subjects without IA, and patients with early RA (<8 months joint symptoms) Demoruelle MK et al, Abstract 769 Autoantibody (+) Cases (N=42) Early RA (N=12) P-value All Subjects 76% (32) 92% 11 0.421 Never smokers 73% (19/26) 86% (6/7) 0.652 28 Bronchial wall thickening Autoantibody (+) Case Autoantibody (-) Control 29 30 5
Lung biopsy studies of patients with established RA show that similar HRCT findings of airway thickening correlate with inflammatory changes and even BALT. Brown KK, Proc Am Thorac Soc 2007; Rangel-Moreno, J Clin Invest 2006 Could HRCT-airways disease indicate BALT in these Ab(+) subjects? Aim 2: Evaluate proteins and autoantibodies in lung samples from patients with established RA and controls 31 32 Total and citrullinated protein levels are higher in bronchoalveolar lavage (BAL) samples of patients with established RA and ILD 5 patients with established RA and ILD Willis V et al Abstract 2812 5 patients with scleroderma and ILD Tuesday Nov 8 th, Hall F2 32 healthy controls (12 non-smokers, 20 smokers) 120 100 80 RA-related autoantibodies are elevated in BAL from patients with RA and lung disease compared to controls P <0.05 P<0.05 P<0.05 60 40 accp2 RF-IgA RF-IgG RF-IgM 20 0 RA-ILD (N=5) SSC-ILD (N=5) Healthy Controls Nonsmokers (N=12) Healthy Controls Smokers (N=20) 33 Willis V et al Abstract 2812 Tuesday Nov 8 th, Hall F2 34 120 100 80 60 40 20 0 Anti-CCP2 levels are elevated in serum and induced sputa in patients with early RA (<8 months of symptoms) compared to controls P <0.05 P <0.05 Sputa CCP2 Serum CCP2 How RA-related autoantibodies are getting into BAL and sputa? Translocation from blood through inflamed lung tissue? Generation within the lung? Findings from Rangel-Moreno suggest that generation within BALT possible Early RA (N=5) Controls (N=8) Needs evaluation with comparative studies of BAL/sputa and blood, and tissue studies which are underway Willis V et al Abstract 2812 Tuesday Nov 8 th, Hall F2 35 36 6
In summary, these SERA lung studies show: 1) Lungs findings consistent with inflammation in Ab(+) individuals with RA, in most cases in absence of smoking. Supporting that the lungs are at least inflamed in preclinical RA and may be a site of initiation of RA. 2) RA-related autoantibodies are detectable in lung biospecimens from patients with established RA. Going forward, these methods will be used in preclinical studies to study generation of RArelated autoimmunity in the lung. How to prove that the lung is a site of initiation of RA-related autoimmunity? 1a) Demonstrate that the lungs are abnormal in preclinical RA 1b) Demonstrate that RA-related autoimmunity detectable in lung biospecimens in established RA 2) Demonstrate the generation of RA-related autoimmunity in the lung in absence of and prior to joint disease 3) Identify factors that can drive the initiation of RA-related autoimmunity in the lung 4) Demonstrate mechanisms by-which RA-related autoimmunity may start in the lungs and then move to the joints: immune complexes? cells? antigen targeting of joint tissue? 37 38 What specific factors lead to RArelated autoimmunity in the lung? Does process start with the generation of autoantigens? If yes, what generates these autoantigens? Smoking leads to increased PAD and cit-proteins in the lung Makrygiannakis et al, Ann Rheum Disease 2008 Additional work from this group, including identification of similar antigens in the lungs and in the joints in established RA ACR Abstracts 2176, 2179 What specific factors lead to RArelated autoimmunity in the lung? Certain infections may lead to cit-proteins, such as P ging Venables, Lundberg and colleagues Could infection generate autoantigens in the lung? What is the infection? Where does the infection come from? Possible connection between oral and lung inflammation? How long does an infection have to be present to initiate RA? Are there other factors that generate inflammation and autoimmunity in the lung? 39 40 Summary 1) Environmental and clinical factors, and lung biology suggest the lung may be a site of initial generation of RA-related autoimmunity 2) Multiple steps are needed to prove that RA-related autoimmunity is generated in the lung (or any site) 1) Identify the mechanisms of disease development 2) Prevention Environmental factors Inflammatory joint disease/symptomatic RA 3) To take these steps, crucial to identify and study in real-time subjects that are in the preclinical phases of RA Studies in the SERA preclinical RA cohort have already yielded important data regarding the lung in preclinical RA Initial generation of RA-related autoimmunity in the lung due to genetic + environmental interactions Spread of autoimmunity from the lungs to the circulation ( Preclinical RA ) 41 42 7
Studies of the Etiologies of Rheumatoid Arthritis (SERA) UNIV OF COLORADO V. Michael Holers MD Jill Norris PhD Kevin Deane, MD Jason Kolfenbach, MD Lezlie Parrish, MSPH Elaine Hamburger, RN Mark Parish Van Willis Kristen Demoruelle, MD Gary Zerbe, PhD Cathy Chartier-Logan Philip Simonian, MD Jan Hughes-Austin NATIONAL JEWISH HEALTH Kevin Brown, MD Aryeh Fischer, MD Russell Bowler, MD/PhD James Crapo, MD (COPDGene) Douglas Stinson (COPDGene) WRAMC/DoDSR William R Gilliland, MD Jess Edison, MD CEDARS-SINAI, LA Michael Weisman, MD Isabel Pedraza, MD Annie Harrington, MD RAIN, NE Jim O Dell, MD Ted Mikuls, MD FEINSTEIN, NY Peter Gregersen, MD BENAROYA, WA Jane Buckner, MD STANFORD/VAPAHCS, CA William H. Robinson, MD BRIGHAM/WOMEN S, MA Elizabeth Karlson, MD UNIVERSITY OF CHICAGO Richard Keating, MD RADIOLOGISTS Brian Petersen, MD MRI Colin Strickland, MD MRI David Lynch, MB CT Peter Sachs, MD CT 43 Walter S. and Lucienne Driskill Foundation NIH FUNDING: R01, K23, T-32, R21, Autoimmunity Prevention Centers (NIAID), General Clinical Research Centers 44 8