scholarly journals Elastase Release by Transmigrating Neutrophils Deactivates Endothelial-bound SDF-1α and Attenuates Subsequent T Lymphocyte Transendothelial Migration

2004 ◽  
Vol 200 (6) ◽  
pp. 713-724 ◽  
Author(s):  
Ravi M. Rao ◽  
Travis V. Betz ◽  
Deanna J. Lamont ◽  
Michael B. Kim ◽  
Sunil K. Shaw ◽  
...  
Keyword(s):  
T Lymphocyte ◽  
Neutrophil Elastase ◽  
Umbilical Vein ◽  
Transendothelial Migration ◽  
Cell Phenotype ◽  
Neutrophil Elastase Inhibitor ◽  
Elastase Inhibitor ◽  
Stromal Cell Derived Factor ◽  
Umbilical Vein Endothelial Cells

Leukocyte trafficking to sites of inflammation follows a defined temporal pattern, and evidence suggests that initial neutrophil transendothelial migration modifies endothelial cell phenotype. We tested the hypothesis that preconditioning of human umbilical vein endothelial cells (HUVEC) by neutrophils would also modify the subsequent transendothelial migration of T lymphocytes across cytokine-stimulated HUVEC in an in vitro flow assay. Using fluorescence microscopy, preconditioning of HUVEC by neutrophils was observed to significantly reduce the extent of subsequent stromal cell–derived factor-1α (SDF-1α [CXCL12])-mediated T lymphocyte transendothelial migration, without reducing accumulation. In contrast, recruitment of a second wave of neutrophils was unaltered. Conditioned medium harvested after transendothelial migration of neutrophils or supernatants from stimulated neutrophils mediated a similar blocking effect, which was negated using a specific neutrophil elastase inhibitor. Furthermore, T lymphocyte transendothelial migration was inhibited by treatment of HUVEC with purified neutrophil elastase, which selectively cleaved the amino terminus of HUVEC-bound SDF-1α, which is required for its chemotactic activity. The reduction in T lymphocyte transendothelial migration was not observed using a different chemokine, ELC (CCL19), and was not reversed by replenishment of SDF-1α, indicating endothelial retention of the inactivated chemokine. In summary, transmigrating neutrophils secrete localized elastase that is protected from plasma inhibitors, and thereby modulate trafficking of other leukocyte subsets by altering the endothelial-associated chemotactic activities.

scholarly journals Novel and Modified Neutrophil Elastase Inhibitor Loaded in Topical Formulations for Psoriasis Management

Pharmaceutics ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 358 ◽  
Author(s):  
Andreia Nunes ◽  
Joana Marto ◽  
Lídia Maria Gonçalves ◽  
Sandra Simões ◽  
Rita Félix ◽  
...  
Keyword(s):  
Serine Protease ◽  
Neutrophil Elastase ◽  
In Vitro Cytotoxicity ◽  
Human Neutrophil Elastase ◽  
Therapeutic Effects ◽  
Neutrophil Elastase Inhibitor ◽  
Analytical Methodology ◽  
Elastase Inhibitor

Human neutrophil elastase (HNE) is a serine protease that degrades matrix proteins. An excess of HNE may trigger several pathological conditions, such as psoriasis. In this work, we aimed to synthesize, characterize and formulate new HNE inhibitors with a 4-oxo-β-lactam scaffold with less toxicity, as well as therapeutic index in a psoriasis context. HNE inhibitors with 4-oxo-β-lactam scaffolds were synthesized and characterized by NMR, FTIR, melting point, mass spectrometry and elemental analysis. In vitro cytotoxicity and serine protease assays were performed. The compound with the highest cell viability (AAN-16) was selected to be incorporated in an emulsion (AAN-16 E) and in a microemulsion (AAN-16 ME). Formulations were characterized in terms of organoleptic properties, pH, rheology, droplet size distribution, in vitro drug release and in vivo psoriatic activity. All compounds were successfully synthesized according to analytical methodology, with good yields. Both formulations presented suitable physicochemical properties. AAN-16 E presented the most promising therapeutic effects in a murine model of psoriasis. Overall, new HNE inhibitors were synthesized with high and selective activity and incorporated into topical emulsions with potential to treat psoriasis.

scholarly journals Platelets enhance neutrophil transendothelial migration via P-selectin glycoprotein ligand-1

2011 ◽  
Vol 300 (2) ◽  
pp. H468-H475 ◽  
Author(s):  
Fong W. Lam ◽  
Alan R. Burns ◽  
C. Wayne Smith ◽  
Rolando E. Rumbaut
Keyword(s):  
Umbilical Vein ◽  
Transendothelial Migration ◽  
Polymorphonuclear Neutrophils ◽  
Dynamic Conditions ◽  
Corneal Injury ◽  
Inflamed Endothelium ◽  
Umbilical Vein Endothelial Cells ◽  
Static Conditions

Platelets are increasingly recognized as important for inflammation in addition to thrombosis. Platelets promote the adhesion of neutrophils [polymorphonuclear neutrophils (PMNs)] to the endothelium; P-selectin and P-selectin glycoprotein ligand (PSGL)-1 have been suggested to participate in these interactions. Whether platelets also promote PMN transmigration across the endothelium is less clear. We tested the hypothesis that platelets enhance PMN transmigration across the inflamed endothelium and that PSGL-1 is involved. We studied the effects of platelets on PMN transmigration in vivo and in vitro using a well-characterized corneal injury model in C57BL/6 mice and IL-1β-stimulated human umbilical vein endothelial cells (HUVECs) under static and dynamic conditions. In vivo, platelet depletion altered PMN emigration from limbal microvessels after injury, with decreased emigration 6 and 12 h after injury. Both PSGL-1−/−and P-selectin−/−mice, but not Mac-1−/−mice, also had reduced PMN emigration at 12 h after injury relative to wild-type control mice. In the in vitro HUVEC model, platelets enhanced PMN transendothelial migration under static and dynamic conditions independent of firm adhesion. Anti-PSGL-1 antibodies markedly inhibited platelet-PMN aggregates, as assessed by flow cytometry, and attenuated the effect of platelets on PMN transmigration under static conditions without affecting firm adhesion. These data support the notion that platelets enhance neutrophil transmigration across the inflamed endothelium both in vivo and in vitro, via a PSGL-1-dependent mechanism.

In vitro and in vivo characterisation of the novel neutrophil elastase inhibitor BI 1323495

2020 ◽  
Author(s):  
Stefan Kreideweiss ◽  
Annette Schuler-Metz ◽  
Christian Gnamm ◽  
Stefan Peters ◽  
Thorsten Oost
Keyword(s):  
Neutrophil Elastase ◽  
The Novel ◽  
Neutrophil Elastase Inhibitor ◽  
Elastase Inhibitor

Carbon monoxide liberated from carbon monoxide-releasing molecule CORM-2 attenuates inflammation in the liver of septic mice

2008 ◽  
Vol 294 (1) ◽  
pp. G184-G191 ◽  
Author(s):  
Gediminas Cepinskas ◽  
Kazuhiro Katada ◽  
Aurelia Bihari ◽  
Richard F. Potter
Keyword(s):  
Carbon Monoxide ◽  
Endothelial Cell ◽  
Umbilical Vein ◽  
Vascular Endothelial Cell ◽  
Cecal Ligation ◽  
Cell Phenotype ◽  
Vascular Endothelial ◽  
Proinflammatory Responses ◽  
Umbilical Vein Endothelial Cells

Recent studies suggest that exogenously administered CO is beneficial for the resolution of acute inflammation. In this study, we assessed the role of CO liberated from a systemically administered tricarbonyldichlororuthenium-(II)-dimer (CORM-2) on modulation of liver inflammation during sepsis. Polymicrobial sepsis in mice was induced by cecal ligation and perforation (CLP). CORM-2 (8 mg/kg iv) was administered immediately after CLP induction, and neutrophil [polymorphonuclear leukocyte (PMN)] tissue accumulation, activation of transcription factor, NF-κB, and changes in adhesion molecule ICAM-1 expression (inflammation-relevant markers) were assessed in murine liver 24 h later. In addition, the effects and potential mechanisms of CORM-2-released CO in modulation of vascular endothelial cell proinflammatory responses were assessed in vitro. To this end, human umbilical vein endothelial cells (HUVEC) were stimulated with LPS (1 μg/ml) in the presence or absence of CORM-2 (10–100 μM) and production of intracellular reactive oxygen species (ROS), (DHR123 oxidation) and NO (DAF-FM nitrosation) and subsequent activation of NF-κB were assessed 4 h later. In parallel, expression of ICAM-1 and inducible NO synthase (iNOS) proteins along with PMN adhesion to LPS-challenged HUVEC were also assessed. Induction of CLP resulted in increased PMN accumulation, ICAM-1 expression, and activation of NF-κB in the liver of septic mice. These effects were significantly attenuated by systemic administration of CORM-2. In in vitro experiments, CORM-2-released CO attenuated LPS-induced production of ROS and NO, activation of NF-κB, increase in ICAM-1 and iNOS protein expression and PMN adhesion to LPS-stimulated HUVEC. Taken together, these findings indicate that CO released from systemically administered CORM-2 provides anti-inflammatory effects by interfering with NF-κB activation and subsequent downregulation of proadhesive vascular endothelial cell phenotype in the liver of septic mice.

scholarly journals Oxidized mucus proteinase inhibitor: a fairly potent neutrophil elastase inhibitor

1994 ◽  
Vol 303 (1) ◽  
pp. 61-68 ◽  
Author(s):  
C Boudier ◽  
J G Bieth
Keyword(s):  
Rate Constant ◽  
Neutrophil Elastase ◽  
Proteinase Inhibitor ◽  
Enzyme Inhibitor ◽  
Fold Increase ◽  
Upper Respiratory Tract ◽  
Neutrophil Elastase Inhibitor ◽  
Active Centre ◽  
Elastase Inhibitor

N-chlorosuccinimide oxidizes one of the methionine residues of mucus proteinase inhibitor with a second-order rate constant of 1.5 M-1.s-1. Cyanogen bromide cleavage and NH2-terminal sequencing show that the modified residue is methionine-73, the P′1 component of the inhibitor's active centre. Oxidation of the inhibitor decreases its neutrophil elastase inhibitory capacity but does not fully abolish it. The kinetic parameters describing the elastase-oxidized inhibitor interaction are: association rate constant kass. = 2.6 x 10(5) M-1.s-1, dissociation rate constant kdiss. = 2.9 x 10(-3) s-1 and equilibrium dissociation constant Ki = 1.1 x 10(-8) M. Comparison with the native inhibitor indicates that oxidation decreases kass. by a factor of 18.8 and increases kdiss. by a factor of 6.4, and therefore leads to a 120-fold increase in Ki. Yet, the oxidized inhibitor may still act as a potent elastase inhibitor in the upper respiratory tract where its concentration is 500-fold higher than Ki, i.e. where the elastase inhibition is pseudo-irreversible. Experiments in vitro with fibrous human lung elastin, the most important natural substrate of elastase, support this view: 1.35 microM elastase is fully inhibited by 5-6 microM oxidized inhibitor whether the enzyme-inhibitor complex is formed in the presence or absence of elastin and whether elastase is pre-adsorbed on elastin or not.

Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

1990 ◽  
Vol 48 (3) ◽  
pp. 914-915
Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold
Keyword(s):  
Plasmodium Falciparum ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Umbilical Vein ◽  
Cell Types ◽  
Amelanotic Melanoma ◽  
Cytoplasmic Process ◽  
Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

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