Quantification of circulating alpha-1-antitrypsin polymers associated with different SERPINA1 genotypes.

OBJECTIVES: Alpha-1-antitrypsin deficiency is a genetic disorder caused by mutations in the SERPINA1 gene encoding alpha-1-antitrypsin (AAT), the major serine protease inhibitor in plasma. Reduced AAT levels are associated with elevated risk of developing emphysema mainly due to uncontrolled activity of neutrophil elastase in the lungs. The prevalent Z-AAT mutant and many rare pathogenic AAT variants also predispose to liver disease due to their accumulation as polymeric chains in hepatocytes. Part of these polymers are secreted into the bloodstream and could represent biomarkers of intra-hepatic accumulation. Moreover, being inactive, they further lower lung protection against proteases. Aim of our study is to accurately quantify the percentage of circulating polymers (CP) in a cohort of subjects with different SERPINA1 genotypes. METHODS: CP concentration was measured in plasma or Dried Blood Spot (DBS) by a sensitive sandwich ELISA based on capture by the polymer-specific 2C1 monoclonal antibody. RESULTS: CP were significantly elevated in patients with the prevalent PI*SZ and PI*ZZ genotypes, with considerable intra-genotype variability. Notably, higher percentage of polymers was observed in association with elevated C-reactive protein. CP levels were also increased in carriers of the Mmalton variant, and of Mprocida, I, Plowell and Mherleen in heterozygosity with Z-AAT. CONCLUSIONS: These findings highlight the importance of implementing CP quantification in a clinical laboratory. Indeed, the variable amount of CP in patients with the same genotype may correlate with the variable severity of the associated lung and liver diseases. Moreover, CP can reveal the polymerogenic potential of newly discovered ultrarare AAT variants.

Comprehensive Clinical Diagnostic Pipelines Reveal New Variants in Alpha-1 Antitrypsin Deficiency.

Alpha-1 antitrypsin deficiency (AATD) is an underdiagnosed disorder associated with mutations in the SERPINA1 gene encoding alpha-1 antitrypsin (AAT). Severe AATD can manifest as pulmonary emphysema and progressive liver disease. Besides the most common pathogenic variants S (E264V) and Z (E342K), many rarer genetic variants of AAT have been found in patients and in the general population. Here we report a panel of new SERPINA1 variants, including 4 null and 16 missense alleles, identified among a cohort of individuals with suspected AATD whose phenotypic follow-up showed inconclusive or atypical results. Because the pathogenic significance of the missense variants was unclear purely on the basis of clinical data, the integration of computational, biochemical, and cellular studies was used to define the associated risk of disease. Established pathogenicity predictors and structural analysis identified a panel of candidate damaging mutations that were characterized by expression in mammalian cell models. Polymer formation, intracellular accumulation, and secretory efficiency were evaluated experimentally. Our results identified two AAT mutants with a Z-like polymerogenic severe deficiency profile (Smilano and Mcampolongo) and three milder variants (Xsarezzo, Pdublin, and Ctiberias). Overall, the experimentally determined behavior of the variants was in agreement with the pathogenicity scores of the REVEL (an ensemble method for predicting the pathogenicity of rare missense variants) predictor, supporting the utility of this bioinformatic tool in the initial assessment of newly identified amino acid substitutions of AAT. Our study, in addition to describing 20 new SERPINA1 variants, provides a model for a multidisciplinary approach to classification of rare AAT variants and their clinical impact on individuals with rare AATD genotypes.

The Genes-Stemness-Secretome Interplay in Malignant Pleural Mesothelioma: Molecular Dynamics and Clinical Hints.

MPM has a uniquely poor somatic mutational landscape, mainly driven by environmental selective pressure. This feature has dramatically limited the development of effective treatment. However, genomic events are known to be associated with MPM progression, and specific genetic signatures emerge from the exceptional crosstalk between neoplastic cells and matrix components, among which one main area of focus is hypoxia. Here we discuss the novel therapeutic strategies focused on the exploitation of MPM genetic asset and its interconnection with the surrounding hypoxic microenvironment as well as transcript products and microvesicles representing both an insight into the pathogenesis and promising actionable targets.

Distribution of the Clinical Manifestations of Alpha 1 Antitrypsin Deficiency in Respiratory Outpatients from an Area of Northern Italy.

BACKGROUND: Alpha 1 antitrypsin deficiency (AATD) is an autosomal codominant genetic condition that affects Caucasians of the European population due to the presence of a deficient allele of the SERPINA1 gene. A frequency of about 1/5,000 individuals has been estimated in Italy. OBJECTIVES: The aim of the study was to evaluate the distribution of the clinical manifestations of severe and intermediate genetic AATD in the geographic area around Parma in Northern Italy. METHOD: 238 subjects were submitted to molecular analysis of the SERPINA1 gene, and data on anthropometric variables, smoking habits, number of packs per year, AAT serum concentration, and clinical manifestations were recorded and presented as mean ± SD or median values (1st quartile; 3rd quartile). RESULTS: The results show a distribution of genetic AATD of 4.1% of the screened population in the area encompassing the city of Parma. PI*MS and PI*MZ were the most common genotypes at 40.9% and 28.2% of the population with genetic AATD, and asthma and emphysema were the most represented clinical manifestations. CONCLUSION: Our study allowed to increase the knowledge of the distribution of genetic AATD in Northern Italy providing information regarding frequencies of genotypes and clinical manifestations of the disorder.

Improving the Laboratory Diagnosis of M-like Variants Related to Alpha1-Antitrypsin Deficiency.

Alpha1-antitrypsin (AAT) is a serine protease inhibitor that is encoded by the highly polymorphic SERPINA1 gene. Mutations in this gene can lead to AAT deficiency (AATD), which is associated with an increased risk of lung and/or liver disease. On the basis of electrophoretic migration, AAT variants are named with capital letters; M (medium) signifies the normal protein. Among pathological variants, the M-like ones represent a heterogeneous group of rare allelic variants that exhibit the same electrophoretic pattern as the M wild-type protein, which makes them difficult to detect with routine methods. In order to avoid their misdiagnosis, the present study defines and validates effective methods for the detection of two pathogenic M-like variants, Mwurzburg and Mwhitstable. Comparison of protein phenotypes using isoelectric focusing of samples that presented the Mwurzburg variant, as revealed by exons 5 sequencing, identified a particular electrophoretic pattern amenable to the Mwurzburg protein. The specific phenotyping pattern was retrospectively validated, thus enabling the detection of 16 patients with Mwurzburg variant among the subjects already tested but not sequenced according to our diagnostic algorithm. The Mwhitstable allele was detected by intron 4 sequencing of SERPINA1 gene. Mwurzburg and Mwhitstable are often misdiagnosed and the introduction of diagnostic improvements can help the clinical management, especially in patients with established lung disease without any other reported risk factors.

Comparison of different algorithms in laboratory diagnosis of alpha1-antitrypsin deficiency.

OBJECTIVES: Alpha1-antitrypsin deficiency (AATD) is an inherited condition that predisposes individuals to an increased risk of developing lung and liver disease. Even though AATD is one of the most widespread inherited diseases in Caucasian populations, only a minority of affected individuals has been detected. Whereas methods have been validated for AATD testing, there is no universally-established algorithm for the detection and diagnosis of the disorder. In order to compare different methods for diagnosing AATD, we carried out a systematic review of the literature on AATD diagnostic algorithms. METHODS: Complete biochemical and molecular analyses of 5,352 samples processed in our laboratory were retrospectively studied using each of the selected algorithms. RESULTS: When applying the diagnostic algorithms to the same samples, the frequency of False Negatives varied from 1.94 to 12.9%, the frequency of True Negatives was 62.91% for each algorithm and the frequency of True Positives ranged from 24.19 to 35.15%. We, therefore, highlighted some differences among Negative Predictive Values, ranging from 0.83 to 0.97. Accordingly, the sensitivity of each algorithm ranged between 0.61 and 0.95. We also postulated 1.108 g/L as optimal AAT cut-off value, in absence of inflammatory status, which points to the possible presence of genetic AATD. CONCLUSIONS: The choice of the diagnostic algorithm has a significant impact on the correct diagnosis of AATD, which is essential for appropriate treatment and medical care. The fairly large number of possible false negative diagnoses revealed by the present paper should also warn clinicians of negative results in patients with clinically-suspected AATD.

Air Trapping Is Associated with Heterozygosity for Alpha-1 Antitrypsin Mutations in Patients with Asthma.

BACKGROUND: Alpha-1 antitrypsin deficiency (AATD) is a hereditary disorder involving lungs, characterized by low serum concentration of the protein alpha-1 antitrypsin (AAT) also called proteinase inhibitor (PI). Asthma is common in AATD patients, but there are only few data on respiratory function in asthmatic patients with AATD. OBJECTIVES: The aim of the study was to evaluate lung function in asthmatic outpatients with mutation in the SERPINA1 gene coding for AAT versus asthmatic subjects without mutation. METHODS: We performed the quantitative analysis of the serum concentration of AAT in 600 outpatients affected by mild to moderate asthma from the University Hospital of Parma, Italy. Fifty-seven of them underwent the genetic analysis subsequently; they were subdivided into mutated and non-mutated subjects. All the mutated patients had a heterozygous genotype, except 1 (PI*SS). We assessed the lung function through a flow-sensing spirometer and the small airway parameters through an impulse oscillometry system. RESULTS: The values of forced vital capacity (% predicted) and those of the residual volume to total lung capacity ratio (%) were, respectively, lower and higher in patients mutated versus patients without mutation, showing a significantly greater air trapping (p = 0.014 and p = 0.017, respectively). Moreover, patients with mutation in comparison to patients without mutation showed lower forced expiratory volume in 3 s (% predicted) and forced expiratory volume in 6 s (L) spirometric values, reflecting a smaller airways contribution. CONCLUSIONS: In asthmatic patients, heterozygosity for AAT with PI*MZ and PI*MS genotypes was associated with small airway dysfunction and with lung air trapping.

Investigating the Link between Alpha-1 Antitrypsin Deficiency and Abdominal Aortic Aneurysms.

BACKGROUND: Alpha-1-Antitrypsin (AAT) is one of the major plasmatic protease inhibitors. In the last decade, an association between Alpha-1-Antitrypsin Deficiency (AATD) and Abdominal Aortic Aneurysms (AAA) has been hypothesized. Multiple factors may be involved in AAA's etiopathogenesis, and an underlying structural defect of the extracellular matrix (ECM) is always present. AATD could be a reasonable risk factor for AAA because it is related to protease/antiprotease imbalance and enhanced ECM degradation of the vessel wall. METHODS: We performed genotyping of 138 patients hospitalized in the Vascular Surgery Division of the ASST-Spedali Civili di Brescia, Italy, for nontraumatic rupture of AAA. The second purpose was to observe the distribution of main nongenetic risk factors for AAA between patients with and without AATD. RESULTS: Out of 138 patients, 22 were found with AATD: 16 MS, 1 SS, 3 MZ, and 2 with a new rare AAT variant. When compared to the general Italian population, our cohort's frequency of deficient S allele was significantly higher (7.8 vs. 2.2% respectively, P < 0.01), whereas the deficient Z allele was similar (1.1 vs. 1.3% respectively, P > 0.05). Although we found no differences in age, gender, hypertension, diabetes, and smoke habits between AAA patients with and without AATD, hyperlipidemia was significantly less frequent in patients with AATD (46.4 vs. 12.5% respectively, P < 0.05). CONCLUSIONS: In our AAA patients' cohort, the S allele frequency was higher than in the general Italian population. Our results support the hypothesis that AATD might be a risk factor for AAA.

The Importance of N186 in the Alpha-1-Antitrypsin Shutter Region Is Revealed by the Novel Bologna Deficiency Variant.

Alpha-1-antitrypsin (AAT) deficiency causes pulmonary disease due to decreased levels of circulating AAT and consequently unbalanced protease activity in the lungs. Deposition of specific AAT variants, such as the common Z AAT, within hepatocytes may also result in liver disease. These deposits are comprised of ordered polymers of AAT formed by an inter-molecular domain swap. The discovery and characterization of rare variants of AAT and other serpins have historically played a crucial role in the dissection of the structural mechanisms leading to AAT polymer formation. Here, we report a severely deficient shutter region variant, Bologna AAT (N186Y), which was identified in five unrelated subjects with different geographical origins. We characterized the new variant by expression in cellular models in comparison with known polymerogenic AAT variants. Bologna AAT showed secretion deficiency and intracellular accumulation as detergent-insoluble polymers. Extracellular polymers were detected in both the culture media of cells expressing Bologna AAT and in the plasma of a patient homozygous for this variant. Structural modelling revealed that the mutation disrupts the hydrogen bonding network in the AAT shutter region. These data support a crucial coordinating role for asparagine 186 and the importance of this network in promoting formation of the native structure.

Electrophoretic α1-globulin for screening of α1-antitrypsin deficient variants.

Background Available screening procedures for the detection of α1-antitrypsin-deficient (AATD) mutations have suboptimal cost-effectiveness ratios. The aim in this study was to evaluate and compare the viability of a composite approach, primarily based on the α1-globulin fraction, in identifying AAT genetic analysis eligible patients against standard screening procedures, based on clinically compatible profiling and circulating AAT < 1 g/L. Methods A total of 21,094 subjects were screened for AATD and deemed eligible when meeting one of these criteria: α1-globulin ≤2.6%; α1-globulin 2.6%-2.9% and AST: >37 U/L and ALT: > 78 U/L; α1-globulin %: 2.9-4.6% and AST: >37 U/L and ALT: >78 U/L and erythrocyte sedimentation rate (ESR) >34 mm/h and C-reactive protein (CRP) >3 mg/L. Subjects were genotyped for the AAT gene mutation. Detection rates, including those of the rarest variants, were compared with results from standard clinical screenings. Siblings of mutated subjects were included in the study, and their results compared. Results Eighty-two subjects were identified. Among these, 51.2% were found to carry some Pi*M variant versus 15.9% who were clinically screened. The detection rates of the screening, including relatives, were: 50.5% for the proposed algorithm and 18.9% for the clinically-based screening. Pi*M variant prevalence in the screened population was in line with previous studies. Interestingly, 46% of subjects with Pi*M variants had an AAT plasma level above the 1 g/L threshold. Conclusions A composite algorithm primarily based on the α1-globulin fraction could effectively identify carriers of Pi*M gene mutation. This approach, not requiring clinical evaluation or AAT serum determination, seems suitable for clinical and epidemiological purposes.

Molecular diagnosis of alpha1-antitrypsin deficiency: A new method based on Luminex technology.

BACKGROUND: Alpha1-antitrypsin deficiency (AATD) is an under-diagnosed hereditary disorder characterized by reduced serum levels of alpha1-antitrypsin (AAT) and increased risk to develop lung and liver diseases at an early age. AAT is encoded by the highly polymorphic SERPINA1 gene. The most common deficiency alleles are S and Z, but more than 150 rare variants lead to low levels of the protein. To identify these pathological allelic variants, sequencing is required. Since traditional sequencing is expensive and time-consuming, we evaluated the accuracy of A1AT Genotyping Test, a new diagnostic genotyping kit which allows to simultaneously identify and genotype 14 deficiency variants of the SERPINA1 gene based on Luminex technology. METHODS: A total of 418 consecutive samples with AATD suspicion and submitted to the Italian Reference laboratory between January and April 2016 were analyzed both by applying the diagnostic algorithm currently in use, and by applying A1AT Genotyping Test. RESULTS: The assay gave the following results: 101 samples (24.2%) were positive for at least one of the 14 deficiency variants, 316 (75.6%) were negative for all the variants analyzed. The identified mutations showed a 100% correlation with the results obtained with our diagnostic algorithm. Seventeen samples (4%) resulted negative for the assay but sequencing identified other rare pathological variants in SERPINA1 gene. CONCLUSION: The A1AT Genotyping Test assay was highly reliable and robust and allowed shorter diagnostic times. In few cases, it has been necessary to sequence the SERPINA1 gene to identify other rare mutations not included in the kit.

Real-world clinical applicability of pathogenicity predictors assessed on SERPINA1 mutations in alpha-1-antitrypsin deficiency.

The growth of publicly available data informing upon genetic variations, mechanisms of disease, and disease subphenotypes offers great potential for personalized medicine. Computational approaches are likely required to assess a large number of novel genetic variants. However, the integration of genetic, structural, and pathophysiological data still represents a challenge for computational predictions and their clinical use. We addressed these issues for alpha-1-antitrypsin deficiency, a disease mediated by mutations in the SERPINA1 gene encoding alpha-1-antitrypsin. We compiled a comprehensive database of SERPINA1 coding mutations and assigned them apparent pathological relevance based upon available data. "Benign" and "pathogenic" variations were used to assess performance of 31 pathogenicity predictors. Well-performing algorithms clustered the subset of variants known to be severely pathogenic with high scores. Eight new mutations identified in the ExAC database and achieving high scores were selected for characterization in cell models and showed secretory deficiency and polymer formation, supporting the predictive power of our computational approach. The behavior of the pathogenic new variants and consistent outliers were rationalized by considering the protein structural context and residue conservation. These findings highlight the potential of computational methods to provide meaningful predictions of the pathogenic significance of novel mutations and identify areas for further investigation.

European Respiratory Society statement: diagnosis and treatment of pulmonary disease in α1-antitrypsin deficiency.

α1-antitrypsin deficiency (AATD) is the most common hereditary disorder in adults. It is associated with an increased risk of developing pulmonary emphysema and liver disease. The pulmonary emphysema in AATD is strongly linked to smoking, but even a proportion of never-smokers develop progressive lung disease. A large proportion of individuals affected remain undiagnosed and therefore without access to appropriate care and treatment.The most recent international statement on AATD was published by the American Thoracic Society and the European Respiratory Society in 2003. Since then there has been a continuous development of novel, more accurate and less expensive genetic diagnostic methods. Furthermore, new outcome parameters have been developed and validated for use in clinical trials and a new series of observational and randomised clinical trials have provided more evidence concerning the efficacy and safety of augmentation therapy, the only specific treatment available for the pulmonary disease associated with AATD.As AATD is a rare disease, it is crucial to organise national and international registries and collect information prospectively about the natural history of the disease. Management of AATD patients must be supervised by national or regional expert centres and inequalities in access to therapies across Europe should be addressed.

Advances in Identifying Urine/Serum Biomarkers in Alpha-1 Antitrypsin Deficiency for More Personalized Future Treatment Strategies.

Alpha1-antitrypsin deficiency (AATD) is a genetic disorder characterized by reduced serum levels of alpha1-antitrypsin (AAT) and increased risk for developing both early-onset lung emphysema and chronic liver disease. Laboratory diagnosis of AATD is not just a matter of degree, although the AAT serum level is the most important determinant for risk of lung damage. While being a single-gene disease, the clinical phenotype of AATD is heterogeneous. The current standard of care for patients affected by AATD-associated pulmonary emphysema is replacement therapy with weekly i.v. infusions of pooled human purified plasma AAT. Although no treatment for liver disease caused by deposition of abnormal AAT in hepatocytes is available, innovative treatments for this condition are on the horizon. This article aims to provide a critical review of the methodological steps that have marked progress in the detection of indicators described in the literature as being "clinically significant" biomarkers of the disease. The development and routine use of specific biomarkers would help both in identifying which patients and when they are eligible for treatment as well as providing additional parameters for monitoring the disease.

Immune activation in α1-antitrypsin-deficiency emphysema. Beyond the protease-antiprotease paradigm.

RATIONALE: α1-Antitrypsin (AAT) is a potent protease inhibitor, deficiency of which is associated with the presence of emphysema. An imbalance of elastase and antielastase, along with innate inflammation in the lung, is believed to cause lung destruction in α1-antitrypsin deficiency (AATD). It is now apparent that AAT has important immune-regulatory roles that would be lost in AATD, yet adaptive immune responses in the lung have not been investigated in patients with AATD. OBJECTIVES: To assess the adaptive immune response in severe AATD emphysema and compare it with that present in "usual" chronic obstructive pulmonary disease (COPD). METHODS: The immune inflammatory response in explanted lungs from 10 subjects with AATD was characterized and quantified, and the results were compared with those of 26 subjects with usual COPD and those of 17 smoking and 11 nonsmoking control subjects with normal lung function. MEASUREMENTS AND MAIN RESULTS: Lymphoid follicles (LFs) in AATD and usual COPD were markedly increased when compared with control groups. Molecular analysis of B lymphocytes in LFs showed predominantly mono/oligoclonality. LF number correlated negatively with FEV1/FVC. B lymphocytes and CD4(+) and CD8(+) T lymphocytes were significantly increased in AATD and usual COPD when compared with control groups. IL-32, an important cytokine in induction of autoimmunity, was markedly up-regulated in AATD and usual COPD. CONCLUSIONS: An important adaptive immune inflammation, comprising B, CD4(+), and CD8(+) lymphocytes, and LFs, is a prominent feature in AATD. These results change the paradigm of the mechanism of AATD-induced emphysema from a pure elastase-antielastase imbalance to a much more complex one involving the adaptive immune system, similarly to what occurs in usual COPD.

Causal and synthetic associations of variants in the SERPINA gene cluster with alpha1-antitrypsin serum levels.

Several infrequent genetic polymorphisms in the SERPINA1 gene are known to substantially reduce concentration of alpha1-antitrypsin (AAT) in the blood. Since low AAT serum levels fail to protect pulmonary tissue from enzymatic degradation, these polymorphisms also increase the risk for early onset chronic obstructive pulmonary disease (COPD). The role of more common SERPINA1 single nucleotide polymorphisms (SNPs) in respiratory health remains poorly understood. We present here an agnostic investigation of genetic determinants of circulating AAT levels in a general population sample by performing a genome-wide association study (GWAS) in 1392 individuals of the SAPALDIA cohort. Five common SNPs, defined by showing minor allele frequencies (MAFs) >5%, reached genome-wide significance, all located in the SERPINA gene cluster at 14q32.13. The top-ranking genotyped SNP rs4905179 was associated with an estimated effect of ß = -0.068 g/L per minor allele (P = 1.20*10(-12)). But denser SERPINA1 locus genotyping in 5569 participants with subsequent stepwise conditional analysis, as well as exon-sequencing in a subsample (N = 410), suggested that AAT serum level is causally determined at this locus by rare (MAF<1%) and low-frequent (MAF 1-5%) variants only, in particular by the well-documented protein inhibitor S and Z (PI S, PI Z) variants. Replication of the association of rs4905179 with AAT serum levels in the Copenhagen City Heart Study (N = 8273) was successful (P<0.0001), as was the replication of its synthetic nature (the effect disappeared after adjusting for PI S and Z, P = 0.57). Extending the analysis to lung function revealed a more complex situation. Only in individuals with severely compromised pulmonary health (N = 397), associations of common SNPs at this locus with lung function were driven by rarer PI S or Z variants. Overall, our meta-analysis of lung function in ever-smokers does not support a functional role of common SNPs in the SERPINA gene cluster in the general population.

Alternative transcripts of the SERPINA1 gene in alpha-1 antitrypsin deficiency.

BACKGROUND: SERPINA1 is the gene for alpha-1 antitrypsin (AAT), an acute phase protein with anti-protease and immunoregulatory activities. Mutations in SERPINA1 gene cause AAT deficiency and predispose individuals to early-onset emphysema and liver diseases. Expression of the SERPINA1 gene is regulated by different promoters and alternative splicing events among non-coding exons 1A, 1B and 1C. METHODS: We have developed three quantitative PCR (QT-PCR) assays (1A, 1B and 1C). These assays were applied for the analysis of SERPINA1 alternative transcripts in: (1) 16 human tissues and (2) peripheral blood leukocytes from 33 subjects with AAT mutations and 7 controls. RESULTS: Tissue-specific expression was found for the SERPINA1 transcripts. The 1A transcripts were mainly expressed in leukocytes and lung tissue while those detected with the 1B assay were highly restricted to leukocytes. Only 1B transcripts significantly correlated with serum AAT levels. The 1C transcripts were specifically found in lung, liver, kidney and pancreas. Furthermore, the expression of transcripts was related to AAT genotypes. While deficient variants of AAT had no pronounced effect on the transcript expression, null alleles were associated with significant reduction of different transcripts. CONCLUSIONS: The possibility to discriminate between SERPINA1 alternative splicing products will help us to understand better the regulation of SERPINA1 gene and its association with SERPINA1 mutations-related diseases.

Italian registry of patients with alpha-1 antitrypsin deficiency: general data and quality of life evaluation.

Alpha1-antitrypsin Deficiency (AATD) is a rare hereditary disorder with an estimated prevalence of about 1/5000 individuals in Italy. Deficient patients are at a higher risk of developing lung emphysema and chronic liver disease. The low estimated prevalence of AATD prompted the establishment of a registry with the aim of learning more about the natural history and the quality of care of these patients. The Italian registry for AATD was established in 1996. In this study, genetic and clinical findings of Italian AATD patients are presented. Moreover, we also evaluated the changes in health-related quality of life (HRQoL) in patients with COPD and AAT deficiency over a three-year period, in relation to augmentation therapy. In a period spanning 18 years (1996-2014) a total of 422 adult subjects with severe AATD were enrolled, namely 258 PI*ZZ, 74 PI*SZ, 4 PI*SS and 86 patients with at least one rare deficient allele. The 21.3% frequency for AATD patients with at least one deficient rare variant is the highest so far recorded in national registries of AATD. The registry data allow a detailed characterization of the natural course of the disease and the level of patient care, as well as confirm the usefulness of early AATD detection.