Alpha-1-antitrypsin deficiency (AATD), also known as alpha1-proteinase inhibitor deficiency, is an autosomal co-dominant condition. The genotypes associated with AATD include null, deficient, and dysfunctional alpha-1-antitrypsin (A1AT) variants, which result in low levels of circulating functional A1AT, unbalanced protease activity, and an increased risk of developing lung emphysema, the leadi...

We were all taught that proteins have to fold correctly to be active and that the primary sequence of amino acids acts as the ’blueprint‘ for successful, productive folding. in recent years, we have also learnt how sensitive that blueprint is to change. For example, a single amino-acid change in the protein sequence, or a subtle change in temperature at which folding takes place, can lead to th...

The homeostatic lung protective effects of alpha-1 antitrypsin (A1AT) may require the transport of circulating proteinase inhibitor across an intact lung endothelial barrier. We hypothesized that uninjured pulmonary endothelial cells transport A1AT to lung epithelial cells. Purified human A1AT was rapidly taken up by confluent primary rat pulmonary endothelial cell monolayers, was secreted extr...

Alpha-1-antitrypsin (A1AT) deficiency is a genetic disease characterized by low levels and/or function of A1AT protein. A1AT deficiency can result in the development of COPD, liver disease, and certain skin conditions. The disease can be diagnosed by demonstrating a low level of A1AT protein and genotype screening for S and Z mutations, which are the most common. However, there are many genetic...

Preliminary studies have suggested that alpha-1-antitrypsin (A1AT) is a useful immunohistochemical marker of histiocytes (monocytes/macrophages) and malignant tumours derived from them. To confirm the reliability of this marker a wide variety of benign and malignant lymphoreticular cells and tissues have been stained by the immunoperoxidase technique for A1AT and positive staining was found to ...

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 patien...

There is evidence that proteases and antiproteases participate in the iron homeostasis of cells and living systems. We tested the postulate that α-1 antitrypsin (A1AT) polymorphism and the consequent deficiency of this antiprotease in humans are associated with a systemic disruption in iron homeostasis. Archived plasma samples from Alpha-1 Foundation (30 MM, 30 MZ, and 30 ZZ individuals) were a...

The bile acid nor-ursodeoxycholic acid (norUDCA) has many biological actions, including antiapoptotic effects. Homozygous PIZZ α-1-antitrypsin (A1AT)-deficient humans are known to be at risk for liver disease, cirrhosis, and liver cancer as a result of the accumulation of the toxic, A1AT mutant Z protein within hepatocytes. This accumulation triggers cell death in the hepatocytes with the large...

The alpha-1-antitrypsin (A1AT) gene is highly polymorphic, with more than 100 genetic variants identified of which some can affect A1AT protein concentration and/or function and lead to pulmonary and/or liver disease. This study reports on the characterization of a p.G320R variant found in two patients, one with emphysema and the other with lung cancer. This variant results from a single base-p...

In addition to exerting a potent anti-elastase function, α-1 antitrypsin (A1AT) maintains the structural integrity of the lung by inhibiting endothelial inflammation and apoptosis. A main serpin secreted in circulation by hepatocytes, A1AT requires uptake by the endothelium to achieve vasculoprotective effects. This active uptake mechanism, which is inhibited by cigarette smoking (CS), involves...