Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tryptases”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources

Immunohistochemical evaluation of mast cells and mark activity tryptase and chymase in experimental fibrosarcoma.

The aim of the study was an evaluation of the activity of mast cells and mark activity tryptase and chymase and of protein levels in experimental fibrosarcoma, induced in rat skin. The experiments were carried out on 50 male Wistar rats. The cancer was induced in rats by one subcutaneous injection of 0.2 mg 3-methylcholanthrene in 0.25 ml of olive oil. Tissue material was fixed in Bouin's fluid. Immunohistochemical tryptase detecting reactions were performed--using specific antibodies and the ABC complex. The activities of tryptase and chymase and protein levels were determined in supernatant of 10% homogenate. We found a very significant growth of mast cell quantity in the connective tissue of tumours. We observed slight differences in the activity of examined enzymes in tumours of different mass.

Animals↗

[Diagnosis of allergic rhinitis by determining of tryptase and eosinophil cationic protein in nasal secretions].

In the last years, the role of nasal mast cells and the eosinophils in the immediate hypersensitivity reaction of allergic rhinitis has been well documented. Tryptase and the eosinophil cationic protein (ECP) are specific activation markers for mast cells and esosinophils respectively. To determine the possible diagnostic value of these markers in allergic rhinitis we measured the levels in both serum and native nasal fluid using sandwich RIA-assays. Twenty eight seasonal allergic patients (16 with active allergy and 12 with extraseasonal allergy) and 11 patients with chronic sinusitis were studied. Twenty one normal healthy donors served as controls. We could not detect increased levels of tryptase and ECP in the serum of all patients and healthy donors. In contrast, patients with active allergy showed very higher levels of ECP than patients of the three other groups. Similarly, nasal ECP was higher in patients with nasal pathology than in healthy subjects. The highest levels were found in the patients with active allergic rhinitis. Our results show that both native nasal fluid tryptase and ECP can be used as markers of local inflammation and that the assessment of their levels can be useful in the diagnosis and follow up of mucosal inflammation in the nose.

Adult↗

Elevated serum tryptase level in a case of intraoperative anaphylaxis caused by latex allergy.

We measured serial serum tryptase levels in a case of intraoperative anaphylaxis caused by allergy to latex. The serum tryptase level was elevated 7 hours after the hypotensive episode and returned to normal after recovery 4 months later. Both skin tests to latex and serum IgE to latex confirmed latex allergy in this patient. To our knowledge, this is the first report of an elevated serum tryptase level in intraoperative anaphylaxis caused by latex allergy. This observation confirms the role of mast cell degranulation in anaphylaxis caused by allergy to latex.

Anaphylaxis↗

Immunohistochemical characterization of mast cell disease in paraffin sections using tryptase, CD68, myeloperoxidase, lysozyme, and CD20 antibodies.

To date, the diagnosis of mast cell disease (MCD) relied on routine plus histochemical stains. Its differential diagnosis, however, includes a variety of other hematopoietic and particularly B-cell lymphoid neoplasms that are best identified in paraffin sections using immunostains. To determine the paraffin-section immunoreactivity of MCD, 20 specimens from 14 patients with MCD and 1 bone marrow sample (from a patient with probable MCD) that showed equivocal metachromasia, were stained with antitryptase, CD68 (KP-1), CD20 (L26), antilysozyme, and antimyeloperoxidase antibodies. Ten hairy cell leukemias (HCLs), six lymphomas of parafollicular and/or monocytoid B-cell (MBCLs) and low-grade mucosa-associated lymphoid tissue (MALT) types, six granulocytic sarcomas, and five acute myeloid leukemias with monocytic differentiation (M4 and M5 types) were also stained. Tryptase positivity was identified in all of the MCD cases. The staining was moderate to strong in 20 of the 21 specimens, including the probable MCD case. No other neoplasms tested were tryptase positive. CD68 showed similar to even stronger staining in all of the specimens of MCD, HCL, granulocytic sarcoma, and acute myeloid leukemia (M4 and M5 types) tested and in five of the six MBCL and/or MALT-type lymphomas. Weak-to-moderate lysozyme staining seemed to be present in at least 7 of the MCD specimens, whereas there was a lack of staining for myeloperoxidase in 12 specimens, and 7 specimens were nonevaluable (1 case was not tested). Myeloperoxidase was identified in all of the granulocytic sarcomas and acute myeloid leukemias (M4 and M5 types) but not in any HCLs, MBCLs, or low-grade lymphomas of MALT type. CD20 was negative in all of the MCD and myelomonocytic neoplasms but positive in all of the HCLs, MBCLs, and low-grade B-cell lymphomas of MALT type. MCD, therefore, has a characteristic tryptase-positive, CD68-positive, and CD20-negative phenotype in paraffin sections. This distinguishes MCD from the hematopoietic and/or lymphoid disorders that it most closely resembles.

Antibodies, Monoclonal↗

[Importance of plasma (histamine and tryptase) and urinary (methylhistamine) in peri-anesthetic anaphylactic and/or anaphylactoid reactions].

Histamine and tryptase, released during anaphylactoid reactions in anaesthesia, can be measured out by radioimmunoassay, provided that their own pharmacokinetic is respected. For two years, we have used sample kits in order to realize the measuring out of these mediators. The aim of this study was to evaluate the interest of these mediators within investigational procedures for anaphylactoid reactions. Eleven anaphylactoid reactions were observed (0,03%). The early blood samples (the first ten minutes following onset of the reaction) were made only in 36% of the cases. Within the serious reactions (grade III), the raising of tryptase indicates the involvement of mast-cell activation. Within minor clinical reactions (grade I), plasma histamine and urinary methylhistamine were the only mediators detected. In an anaphylactic reaction of grade II, which happened after the administering of vecuronium, tryptase was not detected. Therefore, these mediators give the anaesthetists the possibility to prove quickly the severity of the reactions and to direct the investigations very early towards the right way.

Adult↗

Psoriasis patients have highly increased numbers of tryptase-positive mast cells in the duodenal stroma.

We have shown that the number of tryptase-positive mast cells in the duodenal mucosa in psoriasis is increased and that a subgroup of psoriasis patients showed elevated levels of antibodies to gliadin (some of whom also had increased lymphocytes in the duodenal epithelium). Duodenal biopsy specimens from 37 patients with psoriasis (eight mild, 13 moderate and 16 severe) and 22 patients with irritable bowel syndrome (IBS) were examined regarding the presence of tryptase + mast cells. Intraepithelial infiltration by lymphocytes was evaluated and scored from 0 to 3. Patients with psoriasis had 131 +/- 58 mast cells/mm2 (mean +/- SD) and those with IBS 28 +/- 18. Only in four of the 37 psoriasis patients was the number within the range of that in the IBS group. There were no signs of stromal inflammation except in one psoriasis patient. No relationship was found between degree of severity of psoriasis and number of mast cells. In 25 of the 37 specimens from psoriasis patients there was no increase in intraepithelial lymphocytes, whereas seven showed a slight increase (score 1-2) and five a moderate increase (score > or = 2-3). The number of tryptase + mast cells was similar in patients with or without increased intraepithelial lymphocytes. The number of mast cells showed no relation to the presence or absence of antibodies to gliadin. We hypothesize that there are at least two types of abnormalities in the duodenal mucosa in psoriasis, one type that is present in most psoriasis patients and characterized by an increase in mast cells and eosinophils, and another that is present in a subgroup of patients with antibodies to gliadin and an increased number of duodenal intraepithelial lymphocytes. The mechanisms underlying the increase in the number of mast cells and its relevance are not yet known.

Adult↗

Regulation of human mast cell beta-tryptase: conversion of inactive monomer to active tetramer at acid pH.

At neutral pH, human mast cell beta-tryptase is stabilized in its enzymatically active, tetrameric form by heparin, and resists inhibition by biologic protease inhibitors. After dissociation of beta-tryptase from heparin, active tetramers rapidly convert to inactive monomers in an isotonic, neutral pH environment. Although reversible transition states probably exist during this conversion, once inactive monomers form, addition of heparin fails to reconstitute active tetramer at neutral pH. The current study shows that complete reactivation of inactive monomers can occur at acidic pH in a heparin-independent manner. The respective rate-determining steps for formation of tetramer and active enzyme from inactive monomers exhibit second and first order kinetics based on an analysis of initial reaction rates. The optimal pH for tetramer formation and reactivation is about 6, suggesting His residues play a critical role. The optimal ionic strength equivalent is 160 mM NaCl; and the optimal temperature range is 22 degrees C to 37 degrees C. We propose a sequential three-step reactivation process at acidic pH, dimerization of monomers (rate-determining second order step), rapid formation of inactive tetramers, and slow formation of active tetramers (overall rate-determining first order step). Whether reactivation of human beta-tryptase occurs at extracellular or intracellular sites, where the pH is acidic in vivo, should be considered.

Chymases↗

Reversible expression of tryptases and chymases in the jejunal mast cells of mice infected with Trichinella spiralis.

It is has been established that mouse mast cells (MCs) can reversibly alter their expression of serglycin proteoglycans and the homologous granule chymases that have been designated mouse MC protease (mMCP)-1, mMCP-2, and mMCP-5 in vivo. Nevertheless, it remained to be determined whether these immune cells could modify their expression of other chymases and the granule tryptases mMCP-6 and mMCP-7. As assessed immunohistochemically, we now show that MCs reversibly change their expression of the recently described chymase mMCP-9 and both tryptases as these cells traverse the jejunum during the amplification and regression stages of the reactive MC hyperplasia. In noninfected mice, most jejunal MCs reside in the submucosa and express mMCP-6 and mMCP-7, but not mMCP-9 or the chymase mMCP-2. During the inductive phase of the helminth-induced inflammation, when the jejunal MCs move from the submucosa to the tips of the villus, the MCs briefly express mMCP-9, cease expressing mMCP-6 and mMCP-7, and then express mMCP-2. During the recovery phase of the inflammation, jejunal MCs cease expressing mMCP-2 and then express varied combinations of mMCP-6, mMCP-7, and mMCP-9 as they move from the tips of the villus back toward the submucosa. In other model systems, mMCP-6 elicits neutrophil extravasation, and mMCP-7 regulates fibrin deposition and fibrinogen-mediated signaling events. Thus, the ability of a jejunal MC to reversibly alter its tryptase expression during an inflammatory event has important functional implications.

Animals↗

Compound 48/80-induced secretion of histamine from rat peritoneal mast cells depends on a tryptase controlled step also leading to chymase activity.

Compound 48/80 caused activation of rat mast cell tryptase and chymase along with the release of histamine. Following low speed centrifugation, tryptase remained essentially in the supernatant while chymase sedimented. Enzyme activities as well as histamine release were inhibited by phenylmethyl-sulfonyl fluoride and tosyl-lysine chloromethyl ketone, which are respectively unspecific and specific inhibitors of trypsin-like enzymes. Chymostatin inhibited chymase, but not the release of histamine by 48/80. Tryptase activity thus seems to be essentially involved in the mechanism of histamine release, while chymase activity may be merely one of its accompanying events.

Animals↗

Measurement of tryptase in endoscopic gastroduodenal biopsies: distribution and relationship with ulcer disease.

Tryptase, a serine endoprotease, was determined in mucosal biopsies from fundus, corpus, antrum and corpus-fundus of the stomach and from the duodenum in 15 controls, 66 patients with duodenal ulcer, 22 with gastric ulcer and 9 with duodenitis. Intra- and inter-assay coefficients of variation ranged from 3.3% to 8.0% and from 3.5% to 8.6%, respectively. In controls, the highest values for tryptase were found in the fundus and progressively decreased in the corpus, antrum and duodenum. Analysis of variance of data from repeated measurements, performed in six subjects having multiple determinations, achieved statistical significance (F = 16.85, P less than 0.001). Data from the corpus-fundus area documented a significant difference among patient groups (F = 2.70, P less than 0.05). Patients with an active gastric ulcer had higher mean values when compared to controls and to patients with healed gastric ulcer. A similar trend was found in patients with active duodenal ulcer. Furthermore, corpus-fundus tryptase evaluated longitudinally in three patients with an active ulcer (point A) and after healing (point B), showed significant decrease from point A to point B. By contrast it remained elevated or showed only minor decrease in two patients with a persistent active ulcer.

Adult↗

Increased tryptase levels in suction-blister fluid from patients with urticaria.

The levels of tryptase in the suction-blister fluid from patients with chronic urticaria, urticaria pigmentosa, cholinergic urticaria, urticarial dermographism, prurigo of unknown origin, eczema, psoriasis, atopic dermatitis, and from healthy controls were studied. The blister fluid from controls contained up to 15 micrograms/l of tryptase, whereas that from patients with active urticaria contained greater than 50 micrograms/l. This study demonstrates that patients with urticaria have mast cells that readily release tryptase in both the lesional and non-lesional areas of skin.

Adult↗

Tumour necrosis factor stimulates human skin mast cells to release histamine and tryptase.

Besides its effects on tumour cells, tumour necrosis factor (TNF) also acts on a variety of other cells, thus enhancing inflammatory and immune processes. In view of the prominent role of the mast cell in such processes, the aim of the present study was to assess the effects of recombinant TNF-alpha on human mast cells. Mast cells from the infant foreskin obtained during circumcision were dispersed by an enzymatic technique using collagenase and hyaluronidase. Cells thus obtained were pooled, washed and separated by Percoll gradient centrifugation. Mast cells, with a purity of 70-90% were incubated for 60 min with 10(-11) to 10(-7) M rTNF-alpha. Histamine and tryptase levels were assessed in the cell supernatant by spectrofluorometry and radioimmunoassay (RIA) respectively. A concentration dependent release of histamine was observed, which reached a maximum of 11.5 +/- 2.2 nmol/10(6) cells at 10(-8) M rTNF. Release of tryptase was also concentration dependent and reached a maximum of 293 +/- 105 mU/10(6) cells (10(-8) rTNF). rTNF-alpha thus appears to be a direct stimulus for mast cells to degranulate and to release both histamine and tryptase.

Histamine Release↗

Tryptase inhibitors - review of the recent patent literature.

The past several years has seen research increasingly focused around the inhibition of tryptase, a mast cell protease implicated in a myriad of pro-inflammatory responses. Although few compounds have reached the clinic, several monobasic and multibasic small molecules have emerged as promising candidates as a treatment for asthma and other allergic and inflammatory disorders. This summary reviews recent patent activity of tryptase inhibitors and briefly outlines recent tryptase inhibitor literature and clinical updates.

Journal Article↗

Mast cell and neutrophil expression of dog mast cell protease-3. A novel tryptase-related serine protease.

In previous work the primary structure of a previously unknown protease was deduced from the sequence of a dog mastocytoma cDNA. The predicted preproprotein shares some features with mast cell tryptases but is no more than 49% identical in sequence to known trypsin-like enzymes, including dog tryptase. This study explores the expression of this protein, termed dog mast cell protease-3 (dMCP-3). A polyclonal Ab was raised to a peptide corresponding to residues 166-181 of the deduced sequence. Anti-dMCP-3(166-181) Ig recognizes dMCP-3 expressed as a CheY fusion protein in Escherichia coli and binds to a approximately 36-kDa protein in extracts of dog mastocytomas. The Ab does not recognize dog tryptase, dMCP-3s closest known relative in mastocytoma cells. When used with fluorescein-conjugated and alkaline phosphatase-conjugated secondary Abs, anti-dMCP-3(166-181) Ig yields punctate cytoplasmic staining in mastocytoma cells, suggesting localization to intracellular granules. Staining is greatly reduced by preincubation with synthetic dMCP-3 peptide, supporting the specificity of the Ab. Immunohistochemical staining of normal dog tissues reveals scattered dMCP-3 reactive cells in skin, intestine, trachea, and lung parenchyma. Double staining with Ab and methylene blue shows that anti-dMCP-3(166-188) Ig recognizes extravascular mononuclear tissue cells with metachromatic granules. In addition, cytoplasmic staining is seen in polymorphonuclear leukocytes within vessels in tissue sections and in leukocytes harvested from blood. Hybridization of dMCP-3 cDNA to dog skin RNA provides further evidence of dMCP-3 gene transcription in normal tissue. Thus, this study provides immunochemical evidence of dMCP-3 expression in dog mast cell tumors, normal tissue mast cells, and neutrophils.

Amino Acid Sequence↗

Elevated tryptase, nerve growth factor, neurotrophin-3 and glial cell line-derived neurotrophic factor levels in the urine of interstitial cystitis and bladder cancer patients.

PURPOSE: The 2 prominent features of interstitial cystitis are pain and increased numbers of mast cells in the bladder. In this pilot study we determined the concentration of soluble mediators associated with activation of sensory neurons and/or mast cells that were present in the urine. MATERIALS AND METHODS: The study groups included 4 interstitial cystitis patients, 7 kidney donors with no history of bladder disease as negative controls, 6 bladder cancer patients and 7 patients with urinary tract infection as reference controls. Urine samples were assayed for different soluble mediators using immunoassays for tryptase (a marker for mast cell activation), neurotrophic factors (markers of neuronal plasticity) and chemokines (markers of inflammatory cell activity). Results were normalized based on creatinine concentration. RESULTS: There was a marked increase in the average amounts of tryptase and 3 neurotrophic factors in patient urine. Interestingly, the mediator profile in the urine of bladder cancer patients was indistinguishable from that of interstitial cystitis patients with respect to these same 4 proteins. There was no difference between normal control and urinary tract infection urine samples. CONCLUSIONS: These findings may account for several clinical and pathological features found in interstitial cystitis and bladder cancer. Although preliminary due to the limited numbers of patients, they also suggest that increased levels of neurotrophin-3, nerve growth factor, glial cell line-derived neurotrophic factor and tryptase in the urine could serve as a basis for adjunct diagnosis, monitoring and treatment of interstitial cystitis.

Adult↗

Elevated mast cell tryptase in cerebrospinal fluid of multiple sclerosis patients.

Multiple sclerosis (MS) lesions are associated with infiltration of T lymphocytes and macrophages that appear to mediate myelin destruction and gliosis (scarring). Mast cells are located perivascularly in the brain, are juxtaposed to neurons, and have been shown to secrete vasoactive and inflammatory mediators in response to neuropeptides and direct nerve stimulation. Mast cells have been previously identified in MS lesions, are activated by myelin basic protein, and can participate in the regulation of blood-brain barrier permeability, as well as in myelin destruction. Here, cerebrospinal fluid from MS patients and controls with other neurologic diseases was assayed for histamine, its major metabolite methylhistamine, and the specific mast cell marker tryptase. Histamine and methylhistamine were not elevated in MS. However, the mast cell specific proteolytic enzyme tryptase was significantly elevated in MS, suggesting that mast cell activation may be involved in the pathophysiology of this disease.

Adult↗

Effect of MITF on transcription of transmembrane tryptase gene in cultured mast cells of mice.

Mouse mast cell protease (mMCP)-6, mMCP-7 and transmembrane tryptase (TMT) are all tryptases. The normal mi transcription factor (+-MITF) transactivated mMCP-6 gene by binding three consensus motifs in the promoter region, but no MITF-binding motifs were found in the mMCP-7 promoter. Instead, c-Jun transactivated mMCP-7 gene, and +-MITF cooperated with it. The mi-MITF encoded by mutant mi allele inhibited the transactivation by c-Jun and reduced the mMCP-7 promoter activity. Here, the effect of MITF on the TMT gene expression was examined. The +-MITF enhanced the TMT promoter activity by binding two consensus motifs. The mi-MITF showed the inhibitory effect on TMT gene expression. The effect of +-MITF on TMT gene was similar to the effect on mMCP-6 gene, and that of mi-MITF was similar to the effect on mMCP-7 gene. The effects of MITF on TMT gene appeared distinct from its effects on either mMCP-6 or mMCP-7 gene.

Animals↗

Divergent effects of the major mast cell products histamine, tryptase and TNF-alpha on human fibroblast behaviour.

Fibroblast proliferation is a key process in tissue remodeling and mast cells (MCs) are thought to play a crucial role. Having established that the three major MC products, tryptase, histamine and TNF-alpha (TNF) are normally present in human skin MCs, which are in close proximity to dermal fibroblasts, we studied their individual effects on cell cycle-controlled human dermal fibroblasts (HFFF2). These cells express receptors (H1, PAR2, TNFR1/2) for the major MC mediators, but only tryptase or a PAR2 agonist peptide stimulated proliferation and gene expression. TNF was antimitotic, and histamine, while elevating intracellular Ca2+ levels at high concentrations, did not affect proliferation. We conclude that MC products but also composition and numbers of respective receptors on fibroblasts are crucially responsible for fibroproliferative events.

Cell Cycle↗