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Haptoglobin (HP) groups were determined in Chinese patients suffering from eight different diseases and compared to those of 552 control subjects. Patients with cirrhosis of the liver showed a significant difference from controls in the distribution of HP types (p = 2 x 10(-4)), with increases in the HP*1 allele and HP1-1 phenotype frequencies. The relative risk for the HP1-1 phenotype was 3.3.
A 16-year-old girl presented painful, red, nodular lesions on the abdomen. A cutaneous biopsy showed inflammatory cell infiltrate and fibrosis in the dermis and in the septa with isolated adipocyte lobules. alpha1-antitrypsin level was found to be normal but M1S phenotype of alpha1-antitrypsin was determined by isoelectric focusing in polyacrylamide gel. alpha1-antitrypsin level was normal for her family but M2S phenotype was found in her father. Alpha 1-antitrypsin (alpha1 AT) deficiency is a common hereditary disorder of Caucasians. The locus is pleiomorphic and 75 alleles have been identified. Numerous pathological mutations can be classified by the mechanisms which cause the deficiency. The major clinical importance of this deficiency is emphysema and liver disease. Panniculitis is rarely reported and seems to occur principally for the ZZ or MZ phenotype and for low levels of alpha1 AT. MS phenotype has been more rarely reported and triggering agents such as trauma and infections must be present. However, normal levels of alpha1 AT in the serum have previously been reported as in our case, and we suggest the study of alpha1 AT phenotype even if the plasma level is normal.
A new molecular variant of alpha1-antitrypsin was discovered in the family of a woman with severe antitrypsin deficiency and bullous emphysema. The variant resembles the Z variant in most respects in that it results in severe antitrypsin deficiency with the homozygous state and intermediate deficiency with the heterozygous state, and is associated with diastase-resistant, periodic acid-Schiff-positive globules in the liver cells. It differs from the usual Z variant, however, by having normal mobility on acid-starch electrophoresis so that the heterozygous state with the normal M form cannot be distinguished by phenotyping procedures on either acid-starch or alkaline-agarose electrophoresis. The variant has been labeled MDUARTE. A review of phenotype patterns in all patients previously classified as having a homozygous ZZ phenotype reveals extra, fast-moving bands on acid-starch suggestive of an MDUARTEZ heterozygous state in 7.9 per cent of such cases. When intermediate antitrypsin deficiency occurs in the presence of a normal phenotype pattern, one must consider that the patient has inherited either a null gene for antitrypsin synthesis or an MDUARTE variant.
Disruption of the extracellular matrix is believed to play an important role in the pathogenesis of emphysema. Prior studies have demonstrated that transgenic mice expressing the human tissue collagenase, matrix metalloproteinase 1 (MMP-1), develop emphysema. MMP-1 is a protease with substrate specificity for fibrillar collagen. Type I and III collagens, which are the most abundant proteins within the lungs, are the primary substrates for MMP-1. To assess if type I collagen was indeed the site of action for MMP-1 in these transgenic mice, hybrid mice were generated by crossing the MMP-1 transgenic mice with mice that had degradation-resistant type I collagen. The hybrid mice demonstrated an identical emphysematous phenotype as the MMP-1 transgenic mice, indicating that the degradation of type I collagen was not essential to the development of emphysema in these mice. Immunohistochemical studies in control mice demonstrated that collagen fibers in the alveolar walls and ducts of the normal mouse lungs consist mainly of type III collagen. In the transgenic and hybrid mice, the emphysematous changes, which developed, were associated with a marked decrease in type III collagen in these alveolar structures. These results indicate that MMP-1 generated the emphysematous phenotype via the degradative effect on type III collagen, which is a vital structural element of the alveolar walls. This is the first study to show that a matrix metalloproteinase may cause emphysema via its effects on a specific collagen subtype. As such, it should provide important insight into the mechanisms of this disease in humans.
BACKGROUND: alpha1-antitrypsin (AAT) is the main protease inhibitor in the blood. Several different AAT phenotypes exist. The most common variant is the MM phenotype, which is also associated with normal AAT levels. The less common phenotypes with Z and S variants are associated with low AAT levels. AAT deficiency is a risk factor for pulmonary emphysema, liver impairment and some immune-mediated diseases, some of which are also associated with IgA nephropathy (IgAN). In fact, liver impairment resulting from AAT deficiency may directly contribute to renal abnormalities resembling IgAN. PATIENTS AND METHODS: We investigated AAT phenotype and AAT levels in 100 IgAN patients who did not have end-stage liver disease. Fifteen patients in our sample had secondary IgAN. We also tested for the presence of renal deposition of AAT in patients heterozygous for AAT variants as well as in a randomly chosen group of patients with MM phenotype. We checked for any association between AAT phenotype and the progression of IgAN as well as the prevalence of diseases associated with IgAN (i.e. secondary IgAN). RESULTS: Twelve patients in our sample were heterozygous for AAT variants. Phenotypes were MZ in 5 patients, MS in 3, MF in 1, ML in 2 and ME in 1 patient. AAT levels were lower in these 12 patients than in those homozygous for the M variant (1.17+/-0.46 vs. 1.44+/-0.34 g/l, p < 0.05). We found renal deposition of AAT in 2 heterozygous patients and in 1 of the 12 patients which were randomly chosen. End-stage renal (ESRF) failure developed in 3 of the 12 heterozygous patients and in 6 of the 88 homozygous patients (p = 0.07) during the follow-up. The prevalence of heterozygosity was significantly higher in patients with secondary IgAN than in those with primary IgAN ((5/15 vs. 7/85; p < 0.02). CONCLUSIONS: AAT phenotype is not associated with the risk of primary IgA nephropathy, but might have an impact on disease outcome as well as on the risk of secondary IgAN.
Airway smooth muscle (ASM), an important tissue involved in the regulation of bronchomotor tone, exists in the trachea and in the bronchial tree up to the terminal bronchioles. The physiological relevance of ASM in healthy airways remains unclear. Evidence, however, suggests that ASM undergoes marked phenotypic modulation in lung development and in disease states such as asthma, chronic bronchitis and emphysema. The shortening of ASM regulates airway luminal diameter and modulates airway resistance, which can be augmented by cytokines as well as extracellular matrix alterations. ASM may also serve immunomodulatory functions, which are mediated by the secretion of pro-inflammatory mediators such as cytokines and chemokines. In addition, ASM mass increases in chronic airway diseases and may represent either a pathologic or an injury-repair response due to chronic inflammation. This review will present evidence that ASM, a "passive" contractile tissue, may become an "active participant" in modulating inflammation in chronic lung diseases. Cell facts 1. Found in the trachea and along the bronchial tree. 2. Critically important in regulating bronchomotor tone of the airways. 3. Differentiation state is associated with the expression of various "contractile proteins." 4. Displays phenotypic modulation of mechanical, synthetic and proliferative responses. 5. Secretes cytokines, chemokines and extracellular matrix proteins. 6. May serve as a potential new target for the treatment of chronic lung diseases.
A population (n = 526), consisting of employees with COPD, was compared with 2 control populations for the prevalence of Pi-phenotypes. In the patient group, the proportions of ZZ, SZ and MZ were significantly elevated. Among the patient population a prospective study was carried out to evaluate the role of alpha 1-antitrypsin deficiency as a cofactor in COPD. Severity of disease was estimated by standard pulmonary function tests, X-ray signs for emphysema and clinical assessment. Patients with ZZ, SZ and MZ were significantly worse than their MM partners. An influence of MS cannot be rejected. Phenotyping of all patients with COPD is advocated. Screening can also be by determining the ratio of alpha 1-antitrypsin and acid alpha 1-glycoprotein concentrations, which allowed detection of all ZZ, SZ, MZ and about 60% of the MS patients.
OBJECTIVE: alpha 1-Antitrypsin (alpha 1-AT) deficiency is a hereditary disorder characterized by a high risk for the development of emphysema at an early age. In 1988, the National Heart, Lung and Blood Institute, National Institutes of Health, initiated a registry of individuals with alpha 1-AT deficiency to help define the natural history and clinical course of this disorder. This article describes demographic and clinical characteristics of subjects enrolled in the Registry at baseline. DESIGN: Prospective longitudinal natural history study. SETTING: Thirty-seven clinical centers in the United States (36 centers) and Canada (one center). PATIENTS: There were 1,129 subjects 18 years of age or older with severe deficiency of alpha 1-AT, defined as having serum alpha 1-AT levels < or = 11 mumol/L confirmed by a Central Phenotyping Laboratory, or a ZZ or ZNull genotype identified by genomic DNA analysis. RESULTS: Most enrollees were symptomatic white subjects in their fourth to sixth decade, with a ZZ phenotype, a history of having smoked cigarettes, and pulmonary function tests demonstrating a pattern consistent with emphysema. Interestingly, only a small percentage were current smokers on enrollment, suggesting that this population is amenable to smoking cessation. A subgroup of individuals in the Registry with relatively normal lung function were younger, more likely to have never smoked and more likely to have come to medical attention owing to a family history of alpha 1-AT deficiency rather than symptomatic involvement. CONCLUSIONS: These results emphasize the need for increased awareness and early detection of alpha 1-AT deficiency. In this endeavor, dissemination of the information contained in the Registry to health-care professionals and the general population, along with initiation of appropriate preventative measures before significant lung damage has occurred, could have considerable benefits for individuals with this condition.
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Twenty-two patients with rheumatoid arthritis and severe chronic bronchial suppuration are described. In 11 patients the respiratory symptoms appeared after the onset of arthritis at an unusually late age. We discuss causes for the disease association, in particular the possibility that disease modifying drugs in rheumatoid arthritis may predispose to the development of chronic bronchial suppuration; such a possibility requires prospective investigation.
A 70-year-old man with homozygous alpha1-antitrypsin deficiency (AATD) (Pi-ZZ phenotype) at tutopsy was found to have a hepatocellular carcinoma and hepatic fibrosis, pulmonary emphysema, and cor pulmonale. Characteristic cytoplasmic inclusion bodies, with identical histochemical and ultrastructural features, were detected in both normal and malignant liver cells. It is suggested that AATD may precede malignancy, since this is the eleventh case report of this association.
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BACKGROUND: The role of lung volume reduction surgery (LVRS) for individuals with alpha-1 antitrypsin (AAT) deficiency is unclear. METHODS: To assess the role of LVRS in individuals with severe deficiency of AAT, outcomes within the National Emphysema Treatment Trial were analyzed. RESULTS: Of 1218 randomized subjects, 16 (1.3%) had severe AAT deficiency (serum level < 80 mg/dL) and a consistent phenotype (when available). Characteristics of these 16 patients include 87.5% male; median serum AAT level, 55.5 mg/dL; age, 66 years; forced expiratory volume in 1 second (FEV1), 27% predicted; and 50% had upper-lobe-predominant emphysema. All 10 subjects randomized to LVRS underwent the procedure. Although the small number of subjects hampered statistical analysis, 2-year mortality was higher with surgery (20% versus 0%) than with medical treatment. Comparison of outcomes between the 10 AAT-deficient and the 554 AAT-replete subjects undergoing LVRS showed a greater increase in exercise capacity at 6 months in replete subjects and a trend toward lower and shorter duration FEV1 rise in deficient individuals. CONCLUSIONS: This study extends to 49 cases the published experience of LVRS in severe AAT deficiency. Although the small number of subjects precludes firm conclusions, trends of lower magnitude and duration of FEV1 rise after surgery in AAT-deficient versus AAT-replete subjects and higher mortality in deficient individuals randomized to surgery versus medical treatment suggest caution in recommending LVRS in AAT deficiency.
We report on a 43-year-old male patient with Ehlers-Danlos syndrome (EDS) type IV with acute myocardial infarction (MI) without organic coronary stenosis. The disease was complicated with pneumothorax, subcutaneous and mediastinal emphysema, and splenic artery rupture. Three of the patient's family members suffered sudden cardiac death or MI. A diagnosis of EDS type IV was confirmed by decreased production of type III collagen by 86%. Mutation analysis revealed a point mutation in the COL3A1 gene that substituted glycine for aspartate at amino acid position 877. This mutation had not been reported as pathogenic for EDS type IV. These findings suggest close linkage between the mutation and the phenotype with familial MI.
There is indirect evidence that unopposed human neutrophil elastase (HNE) is responsible for emphysema in patients with alpha 1-proteinase inhibitor (Pi) deficiency. To directly explore this possibility, we developed an assay for fibrinopeptide A alpha 1-21 and its degradation products and used it to measure HNE activity in 128 subjects of known Pi phenotype. The mean elastase-specific fibrinopeptide (ESF) level in 49 deficient PiZ individuals is significantly higher than that in 56 PiMZ heterozygotes (4.5 and 1.5 nM, respectively; P less than 0.01), while the mean ESF value in heterozygotes is significantly elevated over that in 23 normal PiM subjects (1.5 and 0.6 nM, respectively; P less than 0.01), consistent with increased HNE activity in those deficient in the major regulator of the enzyme. These results are not due to differences in smoking history because after correction for pack-years of smoking, ESF values in PiZ subjects are fourfold higher than those in PiMZ individuals (P = 0.005), while the ESF levels in heterozygotes are threefold higher than those in PiM subjects (P = 0.02). In addition, this analysis suggests that cigarette smoking and alpha 1-proteinase inhibitor deficiency have additive effects on ESF levels thereby explaining why PiZ and some PiMZ individuals are at especially high risk for the development of lung disease if they smoke. Finally, the observation that ESF levels in nonsmoking PiZ subjects are inversely related to the percent of predicted forced expiratory volume in 1 s (FEV 1%) provides direct support for the concept that unregulated HNE activity causes alveolar septal destruction in patients with alpha 1-proteinase inhibitor deficiency.
A total of 161 patients with chronic obstructive pulmonary disease (COPD) plus 100 control subjects (identified during a study of heart disease in 6,860 Japanese-American men aged 52 to 75 years who were residing in Hawaii) were analyzed for phenotype in search of the antitrypsin gene Z, which has been shown to be associated with pulmonary emphysema in other racial groups. No carriers of the Z gene were found, and the question of whether the rarity or absence of this gene relates to a low frequency of COPD among Japanese-Americans is reviewed.
The alpha 1-antitrypsin (AAT) or protease inhibitor (Pi) genetic polymorphism was studied in 144 white, 100 coloured, 104 Indian and 127 black (Northern Sotho) healthy individuals (controls), in the Pretoria area. Their Pi phenotype and gene frequency distributions are compared with world-wide data on other population groups. The severely deficient Pi phenotypes S, Z and SZ jointly attain frequencies of 0.3-0.4% in coloureds and whites; in blacks and Indians the corresponding frequencies are very much lower. The implication for preventive medicine and public health is that in South Africa the sequelae of Pi deficiencies such as cirrhosis of the liver and/or emphysema of the lung are of practical importance in whites and coloureds and much less so in blacks and Indians. In 176 white breast cancer patients studied, the Pi phenotype and gene frequency distributions were found to be similar to those of healthy controls (not statistically significant). Cohorts of other patients were also phenotyped because of their low alpha 1-globulin concentrations in routine serum protein electrophoresis and/or their specific disease condition (cirrhosis of the liver or emphysema of the lung) known to be associated with AAT deficiency. These results are discussed in terms of their significance for family follow-up, genetic counselling and a preventive service. The need to avoid atmospheric pollution, especially cigarette smoke, is emphasised as a major and cost-effective preventive measure.