Neprilysin

In this study, we examined the role of neprilysin (NEP), a key membrane-bound endopeptidase, in the inflammatory response induced by diesel exhaust emissions (DEE) in the airways through a number of approaches: in vitro, animal, and controlled human exposure. Our specific aims were (1) to examine the role of NEP in inflammatory injury induced by diesel exhaust particles (DEP) using Nep-intact (wild-type) and Nep-null mice; (2) to examine which components of DEP are associated with NEP downregulation in vitro; (3) to determine the molecular impact of DEP exposure and decreased NEP expression on airway epithelial cells' gene expression in vitro, using a combination of RNA interference (RNAi) and microarray approaches; and (4) to evaluate the effects on NEP activity of human exposure to DEE. We report four main results: First, we found that exposure of normal mice to DEP consisting of standard reference material (SRM) 2975 via intratracheal installation can downregulate NEP express...

Clinical trials in heart failure have focused on the improvement in symptoms or decreases in the risk of death and other cardiovascular events. Little is known about the effect of drugs on the risk of clinical deterioration in surviving patients. We compared the angiotensin-neprilysin inhibitor LCZ696 (400 mg daily) with the angiotensin-converting enzyme inhibitor enalapril (20 mg daily) in 8399 patients with heart failure and reduced ejection fraction in a double-blind trial. The analyses focused on prespecified measures of nonfatal clinical deterioration. In comparison with the enalapril group, fewer LCZ696-treated patients required intensification of medical treatment for heart failure (520 versus 604; hazard ratio, 0.84; 95% confidence interval, 0.74-0.94; P=0.003) or an emergency department visit for worsening heart failure (hazard ratio, 0.66; 95% confidence interval, 0.52-0.85; P=0.001). The patients in the LCZ696 group had 23% fewer hospitalizations for worsening heart failu...

Aims: Follicular lymphoma is frequently associated with t(14;18)(q32;q21) translocation. This study was undertaken to determine the pattern of Bcl-2, CD10 and Bcl-6 expression in relation to t(14;18) translocation in follicular lymphoma from a cohort of a multi-ethnic Asian population. Methods and results: Sixty-two cases of follicular lymphoma were retrieved for immunohistochemistry, and t(14;18) translocation analysis by polymerase chain reaction and fluorescent in-situ hybridization techniques. Bcl-2 expression was present in 74% of the cases. CD10 expression was also relatively low (61%), with decreasing frequency of expression in high-grade tumours. Bcl-6 protein was expressed in most of the tumours (88%) regardless of the tumour grade. The t(14;18) translocation was detected in 46 cases (74%) with an extremely high rate of t(14;18) translocation in ethnic Indian cases (100%). Conclusion: The frequency of t(14;18) translocation in this series of follicular lymphomas was higher ...

We investigated whether the absence of Phex (phosphate-regulating gene with homologies to endopeptidases on the X chromosome) in the Hyp mouse affects the expression and activity of neprilysin (NEP) and of endothelin-converting enzyme-like endopeptidase (ECEL1/DINE) in bone marrow stromal cells (BMSC) and osteoblasts (Ob). Total NEP-like activity was higher in Ob than in BMSC regardless of genotype, and Hyp cells showed higher activities than normal. Conditioned media (CM) from Hyp BMSC and Ob inhibited inorganic phosphate (Pi) uptake by mouse proximal tubule cells, and incubating Hyp Ob with phosphoramidon prevented the production of the inhibitor of renal Pi uptake. A linear relationship was observed between the NEP-like activity of Hyp and normal cells and the inhibition of Piuptake. NEP and ECEL1/DINE mRNA levels were higher in Hypcells than in normal cells, and in situ hybridization of ECEL1/DINE confirmed higher levels of expression in the Hyp mouse than in normal cells. In co...

To characterize the tachykininergic effects in fire smoke (FS)-induced acute respiratory distress syndrome (ARDS), we designed a series of studies in rats. Initially, 20 min of FS inhalation induced a significant increase of substance P (SP) in bronchoalveolar lavage fluid (BALF) at 1 h and persisted for 24 h after insult. Conversely, FS disrupted 51.4, 55.6, 46.3, and 43.0% enzymatic activity of neutral endopeptidase (NEP, a primary hydrolyzing enzyme for SP) 1, 6, 12, and 24 h after insult, respectively. Immunolabeling density of NEP in the airway epithelium largely disappeared 1 h after insult due to acute cell damage and shedding. These changes were also accompanied by extensive influx of albumin and granulocytes/lymphocytes in BALF. Furthermore, levels of BALF SP and tissue NEP activity dose dependently increased and decreased, respectively, following 0, low (10 min), and high (20 min) levels of FS inhalation. However, neither the time-course nor the dose-response study observe...

The gene specifying an endopeptidase of Lactococcus lactis, named pepO, was cloned from a genomic library of L. lactis subsp. cremoris P8-2-47 in lambda EMBL3 and was subsequently sequenced. pepO is probably the last gene of an operon encoding the binding-protein-dependent oligopeptide transport system of L. lactis. The inferred amino acid sequence of PepO showed that the lactococcal endopeptidase has a marked similarity to the mammalian neutral endopeptidase EC 3.4.24.11 (enkephalinase), whereas no obvious sequence similarity with any bacterial enzyme was found. By means of gene disruption, a pepO-negative mutant was constructed. Growth and acid production of the mutant strain in milk were not affected, indicating that the endopeptidase is not essential for growth of L. lactis in milk.

Key Points CD10 as a marker discriminating mature from immature neutrophils within heterogeneous neutrophil populations in pathological settings. Immunosuppressive mature CD66b+CD10+ and immunostimulatory immature CD66b+CD10− neutrophils coexist in G-CSF–treated donors.

Characterization of tumors at the molecular level has improved our knowledge of cancer causation and progression. Proteomic analysis of their signaling pathways promises to enhance our understanding of cancer aberrations at the functional level, but this requires accurate and robust tools. Here, we develop a state of the art quantitative mass spectrometric pipeline to characterize formalin-fixed paraffin-embedded (FFPE) tissues of patients with closely related subtypes of diffuse large B-cell lymphoma (DLBCL). We combined a super-SILAC approach with label-free quantification (hybrid LFQ), to address situations where the protein is absent in the super-SILAC standard yet present in the patient samples. Shotgun proteomic analysis on a quadrupole Orbitrap quantified almost 9000 tumor proteins in 20 patients. The quantitative accuracy of our approach allowed the segregation of DLBCL patients according to their cell-of-origin, using both their global protein expression patterns and the 55...

Background Addictive-like behaviors (e.g., hoarding and shopping) may be the result of the cumulative effects of dopaminergic and other neurotransmitter genetic variants as well as elevated stress levels. We, therefore, propose that dopamine homeostasis may be the preferred goal in combating such challenging and unwanted behaviors, when simple dopaminergic activation through potent agonists may not provide any resolution. Case presentation C.J. is a 38-year-old, single, female, living with her mother. She has a history of substance use disorder as well as attention deficit hyperactivity disorder, inattentive type. She had been stable on buprenorphine/naloxone combination and amphetamine, dextroamphetamine mixed salts for many years when unexpectedly she lost her job for oversleeping and not calling into work. KB200z (a pro-dopamine compound) was added to her regimen for complaints of low drive and motivation. After taking this nutraceutical for 4 weeks, she noticed a marked improvem...

The B203.13 monoclonal antibody was developed by immunizing mice with the B/monocyte biphenotypic cell line B1b. During normal hematopoiesis B203.13 is expressed on a fraction of CD34+ cells, while on mature cells it is only present on B-lymphocytes. We tested this antibody as a marker of childhood B-acute lymphoblastic leukemia (B-ALL). Bone marrow aspirates from 139 cases of early B-ALL and 25 controls were studied. About 40% of the B-ALL patients expressed B203.13. In these patients, B203.13 was constantly co-expressed with CD10, but never co-expressed with CD20, contrary to the controls. The CD10(+)/B203.13(+) phenotype was specific to B-ALL, since CD10(+)/CD20(+) cells from common acute lymphoblastic leukemia (c-ALL) did not express B203.13. We concluded that the use of B203.13 in association with CD10 and CD20 provides meaningful information for distinguishing normal residual B-cells from leukemic B-lymphoblasts and that recurrence of a CD10(+)/B203.13(+) phenotype after trans...

Clinical trials in heart failure have focused on the improvement in symptoms or decreases in the risk of death and other cardiovascular events. Little is known about the effect of drugs on the risk of clinical deterioration in surviving patients. We compared the angiotensin-neprilysin inhibitor LCZ696 (400 mg daily) with the angiotensin-converting enzyme inhibitor enalapril (20 mg daily) in 8399 patients with heart failure and reduced ejection fraction in a double-blind trial. The analyses focused on prespecified measures of nonfatal clinical deterioration. In comparison with the enalapril group, fewer LCZ696-treated patients required intensification of medical treatment for heart failure (520 versus 604; hazard ratio, 0.84; 95% confidence interval, 0.74-0.94; P=0.003) or an emergency department visit for worsening heart failure (hazard ratio, 0.66; 95% confidence interval, 0.52-0.85; P=0.001). The patients in the LCZ696 group had 23% fewer hospitalizations for worsening heart failu...

The common acute lymphoblastic leukemia antigen (CALLA, CD10), which is expressed on early lymphoid progenitors and neutrophils, is the zinc metalloprotease, neutral endopeptidase 24.11 (NEP, "enkephalinase"). The CD10 cell surface enzyme is known to hydrolyze a variety of biologically active peptides including met-enkephalin, formyl-met-leu-phe (f-MLP), and substance P. These three CD10/NEP substrates induce the migration and aggregation of neutrophils, suggesting that each of the peptides can function as a mediator of neutrophil inflammatory responses. Recently, inhibition of CD10/NEP was found to reduce the concentration of metenkephalin needed to activate human and invertebrate granulocytes by several orders of magnitude. Herein we show that f-MLP and substance P induce rapid changes in neutrophil morphology, migration, and adhesion molecule expression, including upregulation of Mo1 (CD11b/CD18) and shedding of LAM-1 (also known as LECAM-1, Leu8, or TQ-1, the human hom...

Waldenstrom macroglobulinemia is a rare lymphoplasmacytic lymphoma characterized by a wide range of clinical presentations related to direct tumor infiltration and the production of IgM. Most commonly it presents with cytopenia, hepatosplenomegaly, lymphadenopathy, constitutional symptoms, and hyperviscosity syndrome. We report a case of Waldenstrom macroglobulinemia in an 60-year-old female who initially presented with intermittent abdominal pain. The patient had no peripheral lymphadenopathy. On extensive investigation she was found to have pancreatic mass. The diagnosis of Waldenstrom macroglobulinemia was established after cytomorphology and immunohistochemical analysis of the patient's bone marrow revealed the presence of a lymphoid/lymphoplasmacytoid-like bone marrow infiltrate along with an elevated serum IgM level. The patient responded both clinically and serologically to chemotherapy. This case is unusual because the patient lacked all common clinical features of Walde...

Axonal polyneuropathies are a frequent cause of progressive disability in the elderly. Common etiologies comprise diabetes mellitus, paraproteinaemia, and inflammatory disorders, but often the underlying causes remain elusive. Late-onset axonal Charcot-Marie-Tooth neuropathy (CMT2) is an autosomal-dominantly inherited condition that manifests in the second half of life and is genetically largely unexplained. We assumed age-dependent penetrance of mutations in a so far unknown gene causing late-onset CMT2. We screened 51 index case subjects with late-onset CMT2 for mutations by whole-exome (WES) and Sanger sequencing and subsequently queried WES repositories for further case subjects carrying mutations in the identified candidate gene. We studied nerve pathology and tissue levels and function of the abnormal protein in order to explore consequences of the mutations. Altogether, we observed heterozygous rare loss-of-function and missense mutations in MME encoding the metalloprotease n...