Search results for "elastase"
showing 10 items of 88 documents
Different behavior of myeloperoxidase in two rodent amoebic liver abscess models.
2016
The protozoan Entamoeba histolytica is the etiological agent of amoebiasis, which can spread to the liver and form amoebic liver abscesses. Histological studies conducted with resistant and susceptible models of amoebic liver abscesses (ALAs) have established that neutrophils are the first cells to contact invasive amoebae at the lesion site. Myeloperoxidase is the most abundant enzyme secreted by neutrophils. It uses hydrogen peroxide secreted by the same cells to oxidize chloride ions and produce hypochlorous acid, which is the most efficient microbicidal system of neutrophils. In a previous report, our group demonstrated that myeloperoxidase presents amoebicidal activity in vitro. The ai…
Propeptide glycosylation and galectin‐3 binding decrease proteolytic activation of human proMMP‐9/progelatinase B
2019
Matrix metalloproteinases (MMPs) are secreted as proenzymes, containing propeptides that interact with the catalytic zinc, thereby controlling MMP activation. The MMP‐9 propeptide is unique in the MMP family because of its post‐translational modification with an N‐linked oligosaccharide. ProMMP‐9 activation by MMP‐3 occurs stepwise by cleavage of the propeptide in an aminoterminal (pro‐AT) and carboxyterminal (pro‐CT) peptide. We chemically synthesized aglycosyl pro‐AT and pro‐CT and purified recombinant glycosylated pro‐ATS f−9. First, we report new cleavage sites in the MMP‐9 propeptide by MMP‐3 and neutrophil elastase. Additionally, we demonstrated with the use of western blot analysis a…
Human neutrophil elastase induces endothelial cell apoptosis by activating the PERK‐CHOP branch of the unfolded protein response
2017
Human neutrophil elastase impacts on atherosclerotic plaque stability by inducing apoptosis in endothelial cells. Our aim was to investigate the proapoptotic mechanism of elastase on endothelial cells and to evaluate the presence of elastase in human plaque material. Human endothelial cells were treated with purified human neutrophil elastase. Apoptosis was assayed by capsase-3/7 activation, TUNEL, and sub-G1 assay. Activation of unfolded protein response (UPR) effector molecules binding Ig protein, soluble X-binding protein-1, protein kinase RNA-like ER kinase (PERK), and C/EBP-homologous protein (CHOP) was analyzed by RT-PCR, immunocytochemistry, and Western blot. Genetic silencing of CHO…
2016
Immunologically, active visceral leishmaniasis (VL) is characterised by profound immunosuppression, severe systemic inflammatory responses and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis, however, their role in human visceral leishmaniasis is poorly understood. In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-l…
Hematologic effects of recombinant human granulocyte colony-stimulating factor in patients with malignancy.
1989
Abstract The effect of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematologic parameters was evaluated in a phase I clinical study in 18 patients with advanced malignancy. G-CSF was administered once daily as a 30-minute infusion for 14 days; three patients each were treated at increasing dose levels of 1, 3, 10, 30, and 60 micrograms kg-1 day-1. A transient decrease in neutrophil and monocyte counts was observed immediately after the G-CSF infusion, followed by a dose-dependent increase of up to 15-fold. G-CSF-induced neutrophils exhibited an increased O2- radical production, and serum levels of enzymes related to granulocyte turnover, including lysozyme and elastas…
Hawthorn extract inhibits human isolated neutrophil functions.
2008
Hawthorn extract is a popular herbal medicine given as adjunctive treatment for chronic heart failure. In contrast to the cardiac properties of hawthorn extract, its anti-inflammatory effect has been scarcely investigated. This study examines the effects of a dry extract of leaves and flowers of Crataegus laevigata on various functional outputs of human neutrophils in vitro. Incubation of human neutrophils obtained from peripheral blood of healthy donors with C. laevigata extract (0.75-250 microg/ml) inhibited N-formyl-Met-Leu-Phe (FMLP)-induced superoxide anion generation, elastase release and chemotactic migration with potency values of 43.6, 21.9, and 31.6 microg/ml, respectively. By con…
Antibodies to Cathepsin G in Crohn's disease
1992
. Antibodies directed against antigens in human neutrophils have proved to be of great diagnostic value in certain systemic vasculitides. Recent reports have focused the attention on these antigens as targets of antibodies in sera of patients with inflammatory bowel disease. We investigated the sera drawn from 60 patients suffering from biopsy proven Crohn's disease and 15 patients with active ulcerative colitis. Using sensitive enzyme-linked immunosorbent assays with purified antigens and Western blotting the following antibodies could be demonstrated: cathepsin G (cat-G) antibodies IgG 38.3%, IgM 13.3%, IgA 23.3% and antibodies against human leucocyte elastase (HLE) IgG, IgA, IgM 3.3%. Lo…
Serum and fecal pancreatic enzymes in beta-thalassemia major
1997
This study, using indirect tests, demonstrated that exocrine pancreatic function is impaired in a proportion of patients with beta-thalassemia major (TM), though this impairment is generally mild or moderate.Impaired structure and function of the exocrine pancreas has been reported in patients with Beta-thalassemia major.In this study we measured fecal fats and serum and fecal pancreatic enzymes in 30 patients (13 M, 17 F) with TM, mean age 22.1 yr (range 14-39) and compared them with those of a matched group of healthy controls. Results were correlated with age, serum ferritin, blood transfusion, and various nutritional parameters. Enzymes assays included: serum pancreatic amylase (PA), li…
The quality of plasma collected by automated apheresis and of recovered plasma from leukodepleted whole blood.
2005
Background There exists a current lack of information about the composition of the different types of plasma. No direct comparisons between apheresis plasma (AP) and recovered plasma (RP) derived from in-line-filtered whole blood (WB) have been published to date. Study design and methods Sixty AP units, 100 RP units from in-line-filtered WB held for 3 hours at 20 degrees C between donation and freezing, and an additional 100 RP units held for 15 hours at 20 degrees C before freezing were analyzed for coagulation factors and inhibitors, total protein, immunoglobulin G (IgG), and hemostasis and proteolysis activation markers. The influence of twice freezing and thawing on clotting factors V, …
MR imaging of pancreatic changes in patients with transfusion-dependent beta-thalassemia major.
1999
The aim of this study was to evaluate MR imaging changes of the pancreas in patients with transfusion-dependent beta-thalassemia major.Twenty patients with transfusion-dependent beta-thalassemia major were examined using MR imaging at 0.5 T, with spin-echo T1-weighted, fast spin-echo T2-weighted, and gradient-echo T2*-weighted sequences. Image analysis was performed to assess pancreas-to-fat signal intensity ratios for all pulse sequences. Pancreatic exocrine and endocrine function and serum ferritin levels were assessed. Twenty healthy volunteers underwent MR imaging with the same three sequences and served as a control group.The pancreas-to-fat signal intensity ratio was significantly dec…