Monkey α1 Antitrypsin ELISA Kit

Introduction. - The alpha-1 antitrypsin (alpha 1-AT) deficiency, most frequently caused by homozygosity for the Z variant (SERPINA1: c.1096 G>A; Glu342Lys), can give rise to two clinical patterns: (i) respiratory impairment with emphysema (mainly in adulthood) because of a pulmonary quantitative defect in anti-elastase activity; (ii) hepatic impairment (mainly in childhood) due to the misfolding of the PiZ protein which accumulates in hepatocytes thus providing cytotoxicity. Current knowledge. To date, the clinical and genetic factors responsible for the development of major hepatic injuries (fibrosis and portal hypertension) during childhood in PiZ patients are not known. Methods. -All rights reserved.The DEFI -ALPHA cohort, created in 2008, aims to inventory and prospectively study all alpha 1-AT deficient children diagnosed and included after occurrence of a hepatic sign. The POLYGEN DEFI-ALPHA PHRC has recently (2013) been added to the project to identify modifiers genes by two complementary approaches: (i) the candidate genes strategy with the SERPINA1, CFTR (cystic fibrosis gene), MAN1B1 and SORL1 genes, these two latter being implied in the degradation of misfolding proteins; (ii) the whole exome sequencing (WES) strategy in families in which the PiZ proband has a PiZ brother or sister free of any hepatic sign. Expected results. - The clinical parameter we want to explain is the apparition of a portal hypertension in PiZ children. In the DEFI-ALPHA project, three criteria will be tested: (i) age of inclusion in the cohort, (ii) the way of inclusion (neo-natal icterus or later hepatic impairment) and (iii) treatment or not with ursodesoxycholic acid and, if so, its duration. Genetically, polymorphisms on the SERPINA1 and MAN1B1 genes have already been associated in the literature with different clinical evolutions of the A1ATD but very inconstantly. Our study thus aims to confirm or not this association. The CFTR and SORL1 genes have never been studied in the alpha 1-AT deficiency. Finally, the whole exome sequencing strategy could allow the discovery of new unexpected modifiers genes in this disease. (C) 2015 SPLF. Published by Elsevier Masson SAS.

High molecular weight serpins are members of a large superfamily of structurally conserved proteins that inactivate target proteinases by a suicide substrate-like mechanism. In vertebrates, different clades of serpins distribute predominantly to either the intracellular or extracellular space. Although much is known about the function, structure, and inhibitory mechanism of circulating serpins such as alpha(1)-antitrypsin (SERPINA1) and antithrombin III (SERPINC1), relatively little is known about the function of the vertebrate intracellular (clade B) serpins. To gain a better understanding of the biology of the intracellular serpins, we initiated a comparative genomics study using Caenorhabditis elegans as a model system. A screen of the C. elegans genomic and cDNA databases revealed nine serpin genes, tandemly arrayed on chromosome V. Although the C. elegans serpins represent a unique clade ( L), they share significant functional homology with members of the clade B group of intracellular serpins, since they lack typical N-terminal signal peptides and reside intracellularly. To determine whether nematode serpins function as proteinase inhibitors, one family member, srp-2, was chosen for further characterization. Biochemical analysis of recombinant SRP-2 protein revealed SRP-2 to be a dual cross-class inhibitor of the apoptosis-related serine proteinase, granzyme B, and the lysosomal cysteine proteinases, cathepsins K, L, S, and V. Analysis of temporal and spatial expression indicated that SRP-2 was present during early embryonic development and highly expressed in the intestine and hypoderm of larval and adult worms. Transgenic animals engineered to overexpress SRP-2 were slow growing and/or arrested at the first, second, or third larval stages. These data suggest that perturbations of serpin-proteinase balance are critical for correct postembryonic development in C. elegans.