&NA; Rationale: Alpha‐1 antitrypsin deficiency, caused primarily by homozygosity for the Z allele of the SERPINA1 gene, is a well‐established genetic cause of chronic obstructive pulmonary disease (COPD). Whether the heterozygous PiMZ genotype for alpha‐1 antitrypsin confers increased risk for COPD has been debated. Objectives: We analyzed 8,271 subjects in the Genetic Epidemiology of COPD (COPDGene) Study, hypothesizing that PiMZ would independently associate with COPD and COPD‐related phenotypes. Methods: The COPDGene Study comprises a multiethnic, cross‐sectional, observational cohort of non‐Hispanic white and African American current and former smokers with at least 10 pack‐years of smoking who were enrolled for detailed clinical and genetic studies of COPD and COPD‐related traits. We performed multivariate logistic regression analysis for moderate to severe COPD and assessed Pi genotype with other relevant covariates in models stratified by race. We analyzed quantitative characteristics on the basis of volumetric computed tomography with generalized linear models controlling for genotype, scanner type, and similar covariates. Results: White PiMZ COPDGene subjects had significantly lower lung function, FEV1 percent predicted (68 ± 28 vs. 75 ± 27; P = 0.0005), and FEV1/FVC ratio (0.59 ± 0.18 vs. 0.63 ± 0.17; P = 0.0008), as well as more radiographic emphysema (P = 0.001), than subjects without alpha‐1 antitrypsin Z risk alleles. Similarly, African American PiMZ subjects had lower lung function, FEV1 percent predicted (65 ± 33 vs. 84 ± 25; P = 0.009) and FEV1/FVC (0.61 ± 0.21 vs. 0.71 ± 0.15; P = 0.03). Conclusions: In the COPDGene Study, we demonstrate that PiMZ heterozygous individuals who smoke are at increased risk for COPD and obstructive lung function impairment compared with Z‐allele noncarriers, regardless of race. Although severe alpha‐1 antitrypsin deficiency is uncommon in African Americans, our study adds further support for initial targeted detection of all subjects with COPD for alpha‐1 antitrypsin deficiency, including African Americans. Clinical trial registered with www.clinicaltrials.gov (NCT00608784).
Alpha-1 antitrypsin (AAT) deficiency-associated emphysema is largely attributed to insufficient inhibition of neutrophil elastase released from neutrophils. Correcting AAT levels using augmentation therapy only slows disease progression, and that suggests a more complex process of lung destruction. Because alveolar macrophages (M phi) express AAT, we propose that the expression and intracellular accumulation of mutated Z-AAT (the most common mutation) compromisesM. function and contributes to emphysema development. Extracellular matrix (ECM) degradation is a hallmark of emphysema pathology. In this study, M phi from individuals with Z-AAT (Z-M phi) have greater proteolytic activity onECMthan do normalM phi. This abnormal Z-M phi activity is not abrogated by supplementation with exogenous AAT and is likely the result of cellular dysfunction induced by intracellular accumulation of Z-AAT. Using pharmacologic inhibitors, we show that several classes of proteases are involved in matrix degradation by Z-M phi. Importantly, compared with normal M phi, the membranebound serine protease, matriptase, is present in Z-M phi at higher levels and contributes to their proteolytic activity on ECM. In addition, we identified matrix metalloproteinase (MMP)-14, a membraneanchored metalloproteinase, as a novel substrate for matriptase, and showed that matriptase regulates the levels of MMP-14 on the cell surface. Thus, high levels of matriptase may contribute to increased ECM degradation by Z-M phi, both directly and through MMP-14 activation. In summary, the expression of Z-AAT in M phi confers increased proteolytic activity on ECM. This proteolytic activity is not rescued by exogenous AAT supplementation and could thus contribute to augmentation resistance in AAT deficiency-associated emphysema.
Alpha-1 antitrypsin deficiency is a monogenic disorder resulting in emphysema due principally to the unopposed effects of neutrophil elastase. We previously reported achieving plasma wild-type alpha-1 antitrypsin concentrations at 2.5%-3.8% of the purported therapeutic level at 1 year after a single intramuscular administration of recombinant adeno-associated virus serotype 1 alpha-1 antitrypsin vector in alpha-1 antitrypsin deficient patients. We analyzed blood and muscle for alpha-1 antitrypsin expression and immune cell response. We also assayed previously reported markers of neutrophil function known to be altered in alpha-1 antitrypsin deficient patients. Here, we report sustained expression at 2.0%-2.5% of the target level from years 1-5 in these same patients without any additional recombinant adeno-associated virus serotype-1 alpha-1 antitrypsin vector administration. In addition, we observed partial correction of disease-associated neutrophil defects, including neutrophil elastase inhibition, markers of degranulation, and membrane-bound anti-neutrophil antibodies. There was also evidence of an active T regulatory cell response (similar to the 1 year data) and an exhausted cytotoxic T cell response to adeno-associated virus serotype-1 capsid. These findings suggest that muscle-based alpha-1 antitrypsin gene replacement is tolerogenic and that stable levels of M-AAT may exert beneficial neutrophil effects at lower concentrations than previously anticipated.
Alpha-1 antitrypsin deficiency (AATD) is a hereditary condition in which less than 10 % of the individuals are identified. This under-recognition is a barrier to lifestyle modifications, genetic counseling, and specific treatment. Targeted screening allows for high detection rates and lower costs than population screening. Little is known about the prevalence and demographic and clinical characteristics of individuals with the main AATD genotypes. We retrospectively analyzed data on adult subjects who underwent targeted screening for AATD from December 2003 to July 2009. AATD testing was ordered according to physician discretion, primarily in patients with COPD and unexplained chronic liver disease. We used an algorithm that begins with dried blood spot (DBS) genotyping and uses DBS alpha-1. We included a total of 37,708 individuals of whom 1 % had the ZZ genotype, the most common genotype associated with severe alpha-1 antitrypsin deficiency in North America. This percentage corresponds to a 48-fold increase in the detection rate when compared to its estimated prevalence in the general population. The age at the time of testing was 57.3 ± 15 years in the overall population and 51.9 ± 13 in PI ZZ individuals (p < 0.001). Although individuals from different races were tested, PI ZZ subjects were of White (87 %), Hispanic (3.2 %), and mixed (0.3 %) race. In PI ZZ subjects, 11 % were current smokers. These individuals were diagnosed 9.2 (95 % CI: 4.2–14.3) years before never-smokers. These data support targeted genotyping for the detection of alpha-1 antitrypsin deficiency in adults.
Study objectives: To describe asthma features in a cohort with 1-antitrypsin (AAT) deficiency, and determine the impact of asthma on FEV1 decline. Background: Asthma may be common in those with AAT deficiency, and may lead to accelerated airflow obstruction. Design: Analysis of data obtained from a 5-year, prospective National Heart, Lung, and Blood Institute registry. Setting: A multicenter registry consisting of 37 clinical centers, a central phenotyping laboratory, and a data analysis center. Participants: A cohort of 1,052 subjects with AAT deficiency. Measurements and results: Asthma was defined as reversible airflow obstruction, recurrent attacks of wheezing, and a reported diagnosis of asthma or allergy with or without an elevated serum IgE level. FEV1 decline was calculated by least-square means with adjustments for covariables. Asthma was present in 21% of the cohort and in 12.5% of those with a normal FEV1. Attacks of wheezing were reported in 66%, the first attack occurring at a mean SD age of 31 16 years. Allergy and asthma was reported in 29% and 38%, respectively. An elevated IgE level occurred in 17% and was significantly associated with signs and symptoms of asthma and an allergy history. Unadjusted FEV1 decline was less in the group without asthma and a normal IgE level ( 48.5 mL/yr) vs the groups with asthma features (> 64 mL/yr) (p 0.002). Multivariable analysis showed that bronchodilator response, age, and smoking were significant predictors for FEV1 decline but not asthma. Conclusions: Symptoms and signs of asthma are common in AAT deficiency and may start at the age of most rapid FEV1 loss. Adjusting for other risk factors such as bronchodilator response, asthma as defined does not lead to an accelerated FEV1 decline. In AAT deficiency, augmentation therapy is not more effective in preventing the loss of lung function in those with asthma compared to those without. (CHEST 2003; 123:765-771)
and risk for liver disease in AATD is needed to direct screening and novel therapies toward patients who could benefit most.In this cross section of older AATD subjects, over one-third had clinically significant liver fibrosis confirmed by biopsy.This is much higher than our previously reported prevalence of 7.9% using patient self-reported data.We also confirmed our previous finding that ALT and GGT for affected subjects fall within normal range, which limits clinical utility.The histologic spectrum was varied both in fibrosis and qualitative presence of AATD globules.Future studies will evaluate clinical risk factors and predictors for advanced liver disease.
α1-Antitrypsin is primarily synthesised in the liver, circulates to the lung and protects pulmonary tissues from proteolytic damage. The Z mutant (Glu342Lys) undergoes inactivating conformational change and polymerises. Polymers are retained within the hepatocyte endoplasmic reticulum (ER) in homozygous (PiZZ) individuals, predisposing the individuals to hepatic cirrhosis and emphysema. Latency is an analogous process of inactivating, intra-molecular conformational change and may co-occur with polymerisation. However, the relationship between latency and polymerisation remained unexplored in the absence of a suitable probe. We have developed a novel monoclonal antibody specific for latent α1-antitrypsin and used it in combination with a polymer-specific antibody, to assess the association of both conformers in vitro, in disease and during augmentation therapy. In vitro kinetics analysis showed polymerisation dominated the pathway but latency could be promoted by stabilising monomeric α1-antitrypsin. Polymers were extensively produced in hepatocytes and a cell line expressing Z α1-antitrypsin but the latent protein was not detected despite manipulation of the secretory pathway. However, α1-antitrypsin augmentation therapy contains latent α1-antitrypsin, as did the plasma of 63/274 PiZZ individuals treated with augmentation therapy but 0/264 who were not receiving this medication (p < 10−14). We conclude that latent α1-antitrypsin is a by-product of the polymerisation pathway, that the intracellular folding environment is resistant to formation of the latent conformer but that augmentation therapy introduces latent α1-antitrypsin into the circulation. A suite of monoclonal antibodies and methodologies developed in this study can characterise α1-antitrypsin folding and conformational transitions, and screen methods to improve augmentation therapy.
Oxidative stress is involved in the pathogenesis of airway obstruction in α1-antitrypsin deficient patients. This may result in a shortening of telomere length, resulting in cellular senescence. To test whether telomere length differs in α1-antitrypsin deficient patients compared with controls, we measured telomere length in DNA from peripheral blood cells of 217 α1-antitrypsin deficient patients and 217 control COPD patients. We also tested for differences in telomere length between DNA from blood and DNA from lung tissue in a subset of 51 controls. We found that telomere length in the blood was significantly longer in α1-antitrypsin deficient COPD patients compared with control COPD patients (p = 1×10(-29)). Telomere length was not related to lung function in α1-antitrypsin deficient patients (p = 0.3122) or in COPD controls (p = 0.1430). Although mean telomere length was significantly shorter in the blood when compared with the lungs (p = 0.0078), telomere length was correlated between the two tissue types (p = 0.0122). Our results indicate that telomere length is better preserved in α1-antitrypsin deficient COPD patients than in non-deficient patients. In addition, measurement of telomere length in the blood may be a suitable surrogate for measurement in the lung.
RATIONALE Pulmonary emphysema overlaps partially with spirometrically defined chronic obstructive pulmonary disease and is heritable, with moderately high familial clustering. OBJECTIVES To complete a genome-wide association study (GWAS) for the percentage of emphysema-like lung on computed tomography in the Multi-Ethnic Study of Atherosclerosis (MESA) Lung/SNP Health Association Resource (SHARe) Study, a large, population-based cohort in the United States. METHODS We determined percent emphysema and upper-lower lobe ratio in emphysema defined by lung regions less than -950 HU on cardiac scans. Genetic analyses were reported combined across four race/ethnic groups: non-Hispanic white (n = 2,587), African American (n = 2,510), Hispanic (n = 2,113), and Chinese (n = 704) and stratified by race and ethnicity. MEASUREMENTS AND MAIN RESULTS Among 7,914 participants, we identified regions at genome-wide significance for percent emphysema in or near SNRPF (rs7957346; P = 2.2 × 10(-8)) and PPT2 (rs10947233; P = 3.2 × 10(-8)), both of which replicated in an additional 6,023 individuals of European ancestry. Both single-nucleotide polymorphisms were previously implicated as genes influencing lung function, and analyses including lung function revealed independent associations for percent emphysema. Among Hispanics, we identified a genetic locus for upper-lower lobe ratio near the α-mannosidase-related gene MAN2B1 (rs10411619; P = 1.1 × 10(-9); minor allele frequency [MAF], 4.4%). Among Chinese, we identified single-nucleotide polymorphisms associated with upper-lower lobe ratio near DHX15 (rs7698250; P = 1.8 × 10(-10); MAF, 2.7%) and MGAT5B (rs7221059; P = 2.7 × 10(-8); MAF, 2.6%), which acts on α-linked mannose. Among African Americans, a locus near a third α-mannosidase-related gene, MAN1C1 (rs12130495; P = 9.9 × 10(-6); MAF, 13.3%) was associated with percent emphysema. CONCLUSIONS Our results suggest that some genes previously identified as influencing lung function are independently associated with emphysema rather than lung function, and that genes related to α-mannosidase may influence risk of emphysema.
To the Editor: Most individuals carry two wild-type M alleles of the SERPINA1 gene which encodes α1-antitrypsin. 95% of severe deficiency of α1-antitrypsin is associated with the Z allele (Glu342Lys; denoted PiZZ in the homozygote), and with the retention and polymerisation of α1-antitrypsin within hepatocytes [1]. These polymers are contained within periodic acid–Schiff-positive, diastase-resistant inclusions that are associated with neonatal hepatitis, cirrhosis and hepatocellular carcinoma. The concomitant lack of circulating α1-antitrypsin predisposes the Z α1-antitrypsin homozygote to early-onset emphysema. Polymers of α1-antitrypsin form within the lung as a result of local inflammation and exposure to cigarette smoke [2]. They have also been identified in the skin of an individual with α1-antitrypsin deficiency and panniculitis [3] and in a renal biopsy from an individual with α1-antitrypsin deficiency and vasculitis [4]. It is unknown whether these polymers form locally or are deposited in these tissues from a circulating source, and whether extrahepatic polymers are associated with any disease phenotypes. We have assessed whether polymers of α1-antitrypsin are present within serum, from where they originate, and whether they are associated with clinical features in individuals with PiZZ α1-antitrypsin deficiency. In this investigation we used ELISA with the anti-α1-antitrypsin polymer monoclonal antibody (2C1) [5] to assess the presence of polymers in the plasma of 1) 518 individuals with PiZZ α1-antitrypsin deficiency; 2) an individual with α1-antitrypsin deficiency who underwent liver transplantation; and 3) 293 individuals with a mixture of α1-antitrypsin phenotypes. The specificity of the 2C1 antibody was confirmed by using it to immunoprecipitate polymers from the plasma of individuals with and without a positive signal …
BACKGROUND:Intravenous alpha-1 antitrypsin protein (AAT) augmentation is a prescribed therapy for severe, genetically determined, alpha-1 antitrypsin deficiency (AATD), a genetic basis for pulmonary emphysema. AAT, a predominant systemic inhibitor of neutrophil elastase thus far has not been shown to decrease elastin degradation in a significant number of patients on this therapy. The objective of this study was to compare levels of biomarkers of elastin degradation in plasma, bronchoalveolar lavage (BALF) fluid and urine before and after beginning AAT augmentation therapy in patients with AATD.METHODS:Desmosine and isodesmosine (DI), which occur only in elastin, are amino acid cross-links in mature elastin. Levels of DI in body fluids measure degradation of elastin and can be measured more specifically by mass spectrometry. This method was used to measure DI levels in plasma, bronchoalveolar lavage fluid and urine in cohorts of severe AATD patients on augmentation, not on augmentation and before and after the initiation of augmentation therapy.RESULTS:Statistically significant reductions in plasma DI and in BALF DI were demonstrated in AATD patients receiving intravenous (IV) augmentation therapy as compared with those not receiving it. Administration by aerosol also produced statistically significant reductions in levels of DI in BALF.CONCLUSIONS:Results indicate that the currently prescribed doses of AAT augmentation inhibit neutrophil elastase adequately to reduce elastin degradation, both systemically and in the lung per se. The currently prescribed doses did not reduce elastin degradation to control levels, which may be possible with higher doses.
Recombinant adeno-associated virus (rAAV) vectors have shown promise for the treatment of several diseases; however, immune-mediated elimination of transduced cells has been suggested to limit and account for a loss of efficacy. To determine whether rAAV vector expression can persist long term, we administered rAAV vectors expressing normal, M-type α-1 antitrypsin (M-AAT) to AAT-deficient subjects at various doses by multiple i.m. injections. M-specific AAT expression was observed in all subjects in a dose-dependent manner and was sustained for more than 1 year in the absence of immune suppression. Muscle biopsies at 1 year had sustained AAT expression and a reduction of inflammatory cells compared with 3 month biopsies. Deep sequencing of the TCR Vβ region from muscle biopsies demonstrated a limited number of T cell clones that emerged at 3 months after vector administration and persisted for 1 year. In situ immunophenotyping revealed a substantial Treg population in muscle biopsy samples containing AAT-expressing myofibers. Approximately 10% of all T cells in muscle were natural Tregs, which were activated in response to AAV capsid. These results suggest that i.m. delivery of rAAV type 1-AAT (rAAV1-AAT) induces a T regulatory response that allows ongoing transgene expression and indicates that immunomodulatory treatments may not be necessary for rAAV-mediated gene therapy.
Evaluation of human antibody responses to alpha-1 antitrypsin (AAT) in clinical trials and clinical practice has been limited by the lack of a validated assay. Here we describe the development and validation of an ELISA method for quantification of human and nonhuman primate antibody responses to human AAT. A reference anti-human AAT serum standard was generated using sera from a cynomolgus macaque injected with a recombinant adeno-associated virus vector expressing human AAT. The ELISA was validated for use with human serum dilutions as low as 1:10 and was able to distinguish between specific responses in cynomolgus serum and non-specific increases in apparent antibody titer in serum from subjects in a clinical trial of an AAT gene therapy vector.
Maintaining serum levels of alpha-1-proteinase inhibitor (A1PI) >11 μM by augmentation with plasma-derived human A1PI is currently the only specific therapy available to treat patients with the genetic deficiency of A1PI. In this study, a new, high-purity (≥90% A1PI in monomeric form), ready-to-use, liquid formulation of A1PI-GLASSIA (Kamada, Ness Ziona, Israel) was compared to PROLASTINÆ (Talecris, Research Triangle Park, NC, now Grifols), both commercially available, FDA-approved products. This multicenter, double-blind, randomized controlled trial with partial cross-over was designed to test the non-inferiority and safety of GLASSIA compared to PROLASTIN, assessing both antigenic and functional A1PI trough levels in subject serum. Non-inferiority of GLASSIA to PROLASTIN was demonstrated by remaining within the lower bounds of the confidence intervals (≤3 μM) for both antigenic and functional A1PI. The study concluded that GLASSIA, a new liquid, ready to use, formulation of A1PI, was not inferior to PROLASTIN and it was well tolerated with a safety profile comparable to PROLASTIN.
Rationale Activation state-dependent secretion of alpha-1 proteinase inhibitor (A1PI) by monocytes and macrophages was first reported in 1985. Since then, monocytes and tissue macrophages have emerged as key sentinels of infection and tissue damage via activation of self-assembling pattern recognition receptors (inflammasomes), which trigger inflammation and cell death in a caspase-1 dependent process. These studies examine the relationship between A1PI expression in primary monocytes and monocytic cell lines, and inflammatory cytokine expression in response to inflammasome directed stimuli. Methods IL-1 β expression was examined in lung macrophages expressing wild type A1PI (A1PI-M) or disease-associated Z isoform A1PI (A1PI-Z). Inflammatory cytokine release was evaluated in THP-1 monocytic cells or THP-1 cells lacking the inflammasome adaptor ASC, transfected with expression vectors encoding A1PI-M or A1PI-Z. A1PI-M was localized within monocytes by immunoprecipitation in hypotonic cell fractions. Cell-free titration of A1PI-M was performed against recombinant active caspase-1 in vitro. Results IL-1 β expression was elevated in lung macrophages expressing A1PI-Z. Overexpression of A1PI-M in THP-1 monocytes reduced secretion of IL-1β and TNF-α. In contrast, overexpression of A1PI-Z enhanced IL-1β and TNF- α secretion in an ASC dependent manner. A1PI-Z-enhanced cytokine release was inhibited by a small molecule caspase-1 inhibitor but not by high levels of exogenous wtA1PI. Cytosolic localization of A1PI-M in monocytes was not diminished with microtubule-inhibiting agents. A1PI-M co-localized with caspase-1 in gel-filtered cytoplasmic THP-1 preparations, and was co-immunoprecipitated with caspase 1 from nigericin-stimulated THP-1 cell lysate. Plasma-derived A1PI inhibited recombinant caspase-1 mediated conversion of a peptide substrate in a dose dependent manner. Conclusions Our results suggest that monocyte/macrophage-expressed A1PI-M antagonizes IL-1β secretion possibly via caspase-1 inhibition, a function which disease-associated A1PI-Z may lack. Therapeutic approaches which limit inflammasome responses in patients with A1PI deficiency, in combination with A1PI augmentation, may provide additional respiratory tissue-sparing benefits.
BACKGROUND & AIMS: Liver disease is a significant cause of death among adults with alpha(1)-antitrypsin (A-AT) deficiency. Age and male sex are reported risk factors for liver disease. In the absence of adequate risk stratification, current recommendations are to intermittently test A-AT-deficient adults for liver function. We evaluated this recommendation in a large group of adults with A-AT deficiency to determine the prevalence of increased levels of alanine aminotransferase (ALT) and identify risk factors for liver disease. METHODS: We used the Alpha-1 Foundation DNA and Tissue Bank to identify a cross section of A-AT-deficient adults (n = 647) with and without liver disease; individuals without A-AT deficiency were used as controls (n = 152). Results from ALT tests were compared between groups. RESULTS: The prevalence of liver disease among individuals with A-AT deficiency was 7.9%; an increased level of ALT was observed in 7.8% of A-AT-deficient individuals, which did not differ significantly from controls. Mean levels of ALT fell within normal range for all groups. An increased level of ALT identified patients with liver disease with 11.9% sensitivity. The level of only gamma-glutamyl transpeptidase was significantly higher in the A-AT-deficient group than in controls (43 vs 30 IU/mL; P < .003). A childhood history of liver disease and male sex were risk factors for adult liver disease in the multivariate analysis. CONCLUSIONS: An increased level of ALT does not identify adults with A-AT deficiency who have liver disease. Male sex and liver disease during childhood might help identify those at risk.
Recombinant adeno-associated virus (rAAV) vectors offer promise for the gene therapy of α(1)-antitrypsin (AAT) deficiency. In our prior trial, an rAAV vector expressing human AAT (rAAV1-CB-hAAT) provided sustained, vector-derived AAT expression for >1 year. In the current phase 2 clinical trial, this same vector, produced by a herpes simplex virus complementation method, was administered to nine AAT-deficient individuals by intramuscular injection at doses of 6.0×10(11), 1.9×10(12), and 6.0×10(12) vector genomes/kg (n=3 subjects/dose). Vector-derived expression of normal (M-type) AAT in serum was dose dependent, peaked on day 30, and persisted for at least 90 days. Vector administration was well tolerated, with only mild injection site reactions and no serious adverse events. Serum creatine kinase was transiently elevated on day 30 in five of six subjects in the two higher dose groups and normalized by day 45. As expected, all subjects developed anti-AAV antibodies and interferon-γ enzyme-linked immunospot responses to AAV peptides, and no subjects developed antibodies to AAT. One subject in the mid-dose group developed T cell responses to a single AAT peptide unassociated with any clinical effects. Muscle biopsies obtained on day 90 showed strong immunostaining for AAT and moderate to marked inflammatory cell infiltrates composed primarily of CD3-reactive T lymphocytes that were primarily of the CD8(+) subtype. These results support the feasibility and safety of AAV gene therapy for AAT deficiency, and indicate that serum levels of vector-derived normal human AAT >20 μg/ml can be achieved. However, further improvements in the design or delivery of rAAV-AAT vectors will be required to achieve therapeutic target serum AAT concentrations.
Background. Alpha-1 antitrypsin deficiency (AAT) is an inherited condition that predisposes to lung and/or liver disease. Objective. The current study examined the clinical features of the PiSS genotype. Methods. Nineteen study participants (PiSS) and 29 matched control participants (PiMM) were telephone interviewed using a standardized questionnaire. Demographic features, cigarette smoking, vocation, medication history, and clinical diagnoses were compared. Statistical analysis was performed. Finally, a comprehensive literature review was performed by two investigators. Results. 12/19 (63.2%) study participants reported the presence of lung and/or liver disease compared to 12/29 (41.4%) control participants. There trended toward having a higher frequency of medication allergies in the study population (42.11% versus 20.69%). Conclusions. The PiSS genotype was associated with a similar incidence of obstructive lung disease to controls. Selective bias intrinsic in testing for AAT deficiency and the rarity of the PiSS genotype will make future study of this association dependent on population-based tests.