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 451 records · Page 25Linked to original sources
PubMed2004

Detection of tryptase-, chymase+ cells in human CD34 bone marrow progenitors.

BACKGROUND: Mast cells (MCs) arise from haematopoietic stem cells. We have recently reported that CD34(+) progenitors derived from human bone marrow (BM) develop into tryptase+, chymase+ MCs when cultured in the presence of recombinant human stem cell factor (rhSCF) and recombinant human IL-6 (rhIL-6). In an experiment for the expression of chymase during differentiation, chymase+ cells were detected in human BM, but tryptase+ cells were not found. OBJECTIVE: The purpose of this study was to show the appearance of chymase+ cells in CD34(+) cells with an origin different from MC differentiation. METHODS: CD34(+) cells from human BM were sorted with anti-CD117 monoclonal antibody (mAb), and cytospins of CD34(+), CD34(+)CD117(+), or CD34(+)CD117(-) were prepared. These cells were cultured with rhSCF+rhIL-6 for 12 weeks. Some of the cells were subjected to either histological stain with Wright-Giemsa or immunocytochemistry with anti-chymase mAb. Real-time RT-PCR was also performed to compare the transcriptional level of chymase from each cell preparation. RESULTS: Chymase was expressed in CD34(+) cells as well as human MCs by immunocytochemistry. Substantial CD34(+)CD117(-) cells, but not CD34(+)CD117(+) cells, were stained immunocytochemically with anti-chymase mAb. For 1 week culture with rhSCF+rhIL-6, no cells expressed chymase in any preparation. Real-time RT-PCR revealed positivity for chymase mRNA in CD34(+) cells, but it reduced at 1 week of culture, and increased as cells developed into MCs. Chymase mRNA in CD34(+)CD117(+) cells was negligible compared with that in CD34(+)CD117(-). Tryptase mRNA was below the detectable level in CD34(+) cells, and increased along with MC differentiation. After 12 weeks of culture, CD34(+)CD117(+) developed predominantly into MCs, whereas CD34(+)CD117(-) developed into monocytes/macrophages. CONCLUSION: Our findings suggested that chymase is present not only in MCs but also in CD34(+)CD117(-) BM progenitors, but that its origin is different from the MC lineage.

Antigens, CD34↗
PubMed2006

Evaluation of neoplastic human mast cells by tryptase-immunoelectron microscopy.

AIMS: To analyse and characterize the ultrastructural morphology of normal tissue mast cells (MC) and neoplastic bone marrow MC. METHODS: We have examined the ultrastructure and cytomorphological features of MC derived from cord blood cells, neoplastic bone marrow MC in patients with systemic mastocytosis (SM, n = 4), myelomastocytic leukaemia (MML, n = 2), mast cell leukaemia (MCL, n = 2) and tryptase-positive acute myeloid leukaemia (AML, n = 4). RESULTS: Based on their ultrastructure and morphology, four distinct cell types could be delineated: (i) mature well-granulated tissue MC exhibiting a round central nucleus; (ii) atypical MC type I with oval nuclei, hypogranulated cytoplasm, and prominent surface projections; (iii) immature atypical MC with bi- or polylobed nuclei (atypical MC type II = promastocytes); and (iv) metachromatic blasts. Type I atypical MC were detected in a patient with indolent SM, whereas type II MC and metachromatic blasts were primarily found in MML, MCL and tryptase-positive AML. In all samples examined, the identity of MC could be reconfirmed by immunoelectron microscopy, irrespective of the stage of cell maturation or the disease variant, all types of MC contained tryptase in their cytoplasmic granules. CONCLUSION: Immunoelectron microscopy may be a helpful approach in confirming the identity of neoplastic MC in myeloid neoplasms.

Adult↗
PubMed2005

Hypotensive shock and angio-oedema from angiotensin II receptor blocker: a class effect in spite of tripled tryptase values.

In adverse reactions with shock, tripled tryptase values can support a diagnosis of anaphylaxis. A 51-year old physically fit woman experienced angio-oedema and hypotensive shock after irbesartan ingestion requiring noradrenaline infusion. Serum tryptase rose to three times the normal value. Total immunoglobulin E and skin prick tests were normal, however. As nonallergic increases in tryptase have been observed, e.g. during angio-oedema from angiotensin-converting enzyme inhibitors, and bradykinin itself can degranulate mast cells acutely, we interpret the reaction as a class effect. To our knowledge, our report is one of the first on shock and angio-oedema from irbesartan.

Angioedema↗
PubMed1996

Fixation with Carnoy's fluid reduces the number of chymase-positive mast cells: not all chymase-positive mast cells are also positive for tryptase.

Mast cells in the nasal mucosa can be studied by means of monoclonal antibodies (mAb) against tryptase (T+MC) and chymase (C+MC). Fixation with acetone gives more positive cells than does fixation with Carnoy's fluid. In frozen biopsy specimens of allergic nasal mucosa fixed with acetone, the number of T+MC equals that of C+MC. When fixed with Carnoy's fluid, however, the number of T+MC is larger than the number of C+MC. The decrease in both T+MC and C+MC resulting from fixation with Carnoy's fluid is time-related and depends on the type of mAb used. Carnoy fixation time gives a decrease in the number of C+MC within 1 min, whereas the number of T+MC decreases only after 10 min. Within 1 min, the number of C+MC decreases to a level where continued fixation no longer gives further decreases in the number of cells. Two populations of mast cells can be distinguished here: one sensitive and the other insensitive to Carnoy's fluid. When double-staining is used, fixation with acetone gives three populations of mast cells: one positive for tryptase (T+C-MC), another positive for tryptase and chymase (T+C+MC), and a third one positive for chymase (T-C+MC). These three populations were found in lymph node, spleen, thymus, dermis, lung parenchyma, small intestinal submucosa, and nasal mucosa.

Acetic Acid↗
PubMed1994

Eosinophil cationic protein, myeloperoxidase and tryptase in children with asthma and atopic dermatitis.

Serum levels of eosinophil cationic protein (ECP), myeloperoxidase (MPO), tryptase, total IgE and differential blood cell counts were studied in atopic children with: 1) moderate to severe asthma using inhaled steroids and symptom-free for the last 3 weeks (n = 13), 2) mild asthma with sporadic symptoms, using only inhaled beta 2-agonists < 3 times/week (n = 15), 3) acute asthmatic attacks admitted to hospital (n = 12), 4) mild to moderate atopic dermatitis (n = 14). Fifteen children without any history of atopy served as controls. ECP, MPO, tryptase and IgE were measured in serum by radioimmunoassays (RIA). The symptom-free children with inhaled steroids had similar median ECP and MPO values as the controls, 8.0 and 360 micrograms/l, vs. 9.0 and 310 micrograms/l, while both ECP and MPO were significantly (p < 0.001) increased in the symptom-free children without anti-inflammatory treatment, 32 and 887 micrograms/l and in those with acute asthma, 28 and 860 micrograms/l. The children with atopic dermatitis had increased ECP but normal MPO levels, 16.0 and 455 micrograms/l. Tryptase in serum was not measurable in any patient. All groups except the control group had significantly elevated total IgE levels. The results indicate that in atopic children serum ECP is a good marker of ongoing asthma or atopic dermatitis. The normal levels of ECP and MPO in the children with asthma using inhaled steroids seem to reflect successful anti-inflammatory treatment. The increased levels of ECP and MPO in the children with mild asthma and no anti-inflammatory treatment may indirectly reflect airway inflammation.

Adolescent↗
PubMed1999

Thrombin and mast cell tryptase regulate guinea-pig myenteric neurons through proteinase-activated receptors-1 and -2.

1. Proteases regulate cells by cleaving proteinase-activated receptors (PARs). Thrombin and trypsin cleave PAR-1 and PAR-2 on neurons and astrocytes of the brain to regulate morphology, growth and survival. We hypothesized that thrombin and mast cell tryptase, which are generated and released during trauma and inflammation, regulate enteric neurons by cleaving PAR-1 and PAR-2. 2. We detected immunoreactive PAR-1 and PAR-2 in > 60 % of neurons from the myenteric plexus of guinea-pig small intestine in primary culture. A large proportion of neurons that expressed substance P, vasoactive intestinal peptide or nitric oxide synthase also expressed PAR-1 and PAR-2. We confirmed expression of PAR-1 and PAR-2 in the myenteric plexus by RT-PCR using primers based on sequences of cloned guinea-pig receptors. 3. Thrombin, trypsin, tryptase, a filtrate from degranulated mast cells, and peptides corresponding to the tethered ligand domains of PAR-1 and PAR-2 increased [Ca2+]i in > 50 % of cultured myenteric neurons. Approximately 60 % of neurons that responded to PAR-1 agonists responded to PAR-2 agonists, and > 90 % of PAR-1 and PAR-2 responsive neurons responded to ATP. 4. These results indicate that a large proportion of myenteric neurons that express excitatory and inhibitory neurotransmitters and purinoceptors also express PAR-1 and PAR-2. Thrombin and tryptase may excite myenteric neurons during trauma and inflammation when prothrombin is activated and mast cells degranulate. This novel action of serine proteases probably contributes to abnormal neurotransmission and motility in the inflamed intestine.

Animals↗
PubMed1994

Metachromatic, IgE-bearing and tryptase-containing cells on the nasal mucosal surface in provoked allergic rhinitis.

We studied the relationship between mast cells or basophils and symptoms in provoked allergic rhinitis. Nasal brush and lavage samples were obtained before nasal allergen challenge and every 2 h for 12 h after the challenge in 10 allergics and 3 controls. The cells were identified by their metachromatic staining properties (brush and lavage samples) or with immunohistochemical methods using specific antibodies to IgE and tryptase, a selective mast-cell marker (brush samples). Histamine was determined in the brush samples using liquid chromatography. After an initial decrease, the numbers of metachromatic, IgE-bearing and tryptase-containing cells, as well as the histamine content of the cells in the brush samples, increased during the subsequent observation hours. The prechallenge cell and histamine values correlated with the symptom score 15 min after the challenge. The prechallenge lavage samples lacked metachromatic cells, but these cells were found in increasing numbers after the provocation. Three of the patients differed from the remaining seven in that their prechallenge brush samples contained many positively stained cells. All patients showed a positive cellular response to the allergen challenge, but these three individuals showed the most vivid response. The morphology of the metachromatic cells in the prechallenge brush samples agreed with that of mast cells, but the morphology of metachromatic cells which outnumbered tryptase-containing cells in samples at 8 to 12 h rather agreed with their being basophils.

Adult↗
PubMed1992

Tryptase Clara, an activating protease for Sendai virus in rat lungs, is involved in pneumopathogenicity.

Tryptase Clara is an arginine-specific serine protease localized exclusively in and secreted from Clara cells of the bronchial epithelium of rats (H. Kido, Y. Yokogoshi, K. Sakai, M. Tashiro, Y. Kishino, A. Fukutomi, and N. Katunuma, J. Biol. Chem. 267:13573-13579, 1992). The purified protease was shown in vitro to behave similarly to trypsin, cleaving the precursor glycoprotein F of Sendai virus at residue Arg-116 and activating viral infectivity in a dose-dependent manner. Anti-tryptase Clara antibody inhibited viral activation by the protease in vitro in lung block cultures and in vivo in infected rats. When the enzyme-specific antibody was administered intranasally to rats that were also infected intranasally with Sendai virus, activation of progeny virus in the lungs was significantly inhibited. Thus, multiple cycles of viral replication were suppressed, resulting in a reduction in lung lesions and in the mortality rate. These findings indicate that tryptase Clara is an activating protease for Sendai virus in rat lungs and is therefore involved in pulmonary pathogenicity of the virus in rats.

Animals↗
PubMed2006

The tryptase positive compact round cell infiltrate of the bone marrow (TROCI-BM): a novel histopathological finding requiring the application of lineage specific markers.

AIMS: Compact tryptase-positive round cell infiltrates of the bone marrow (TROCI-BM) are very rare histopathological findings and may pose challenging problems with regard to the cell type involved (either mast cells or basophilic granulocytes) and the exact diagnosis. METHODS: A selected panel of immunohistochemical markers against mast cell and basophil related antigens, including CD25, CD34, CD117/Kit, and the 2D7 antigen (which is found only in basophilic granulocytes) on a total of 410 routinely processed bone marrow biopsy specimens (including 88 cases of systemic mastocytosis (SM), 20 cases of chronic myeloid leukaemia (CML), 92 cases of myeloid neoplasms other than CML, and 210 controls with normal/reactive bone marrows). RESULTS: In total, 17 cases with TROCI-BM could be identified: 11 SM (including two cases of well-differentiated SM and two mast cell leukaemias; MCL), 2 myelomastocytic leukaemia (MML), 2 CML with excess of basophils (secondary basophilic leukaemia (CMLba)), and 2 tryptase positive acute myeloid leukaemia (AML). Regarding the cell types involved, TROCI-BM cells were found to express CD117/Kit in all cases of SM and MCL. In MML and tryptase postitive AML, TROCI-BM cells were found to coexpress CD34 and Kit. The basophil specific antigen 2D7 was only detected in CD34/Kit negative TROCI-BM cells in two patients with CMLba. The activating point mutation D816V was detected in 8/11 patients with SM but not in any of the other haematological malignancies. CONCLUSIONS: In summary, a total of six rare myeloid neoplasms may present with a novel immunohistochemical phenomenon tentatively termed TROCI-BM.

Adult↗
PubMed2005

Indolent systemic mastocytosis with elevated serum tryptase, absence of skin lesions, and recurrent severe anaphylactoid episodes.

BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms.

Adult↗
PubMed2006

Elevated tryptase levels are associated with greater bone density in a cohort of patients with mastocytosis.

BACKGROUND: Mastocytosis is associated with a pathological increase in tissue mast cells. Associated skeletal problems include a decrease in bone density and pathological fractures. METHODS: In order to explore the relationship between bone density and the severity of mastocytosis, 21 patients with mastocytosis who underwent dual-energy X-ray absorptiometry were entered into this study. Correlation coefficients were computed between Z-scores and demographic, clinical and laboratory data. Femoral neck Z-scores correlated with serum tryptase levels when all the patients were considered (p=0.029). RESULTS AND CONCLUSION: Patients with less severe disease had significantly lower values at the L1-L4 spine (p=0.046) and femoral neck (p=0.029) Z-scores compared to patients with more severe disease. Most patients who had low Z-scores (between -1 and -2.5) were under 50 years of age, had less severe disease and had lower serum tryptase levels. A history of gastroesophageal reflux disease and a history of hypotensive episodes correlated with lower L1-L4 spine Z-scores (p<0.05). Thus, patients with less severe disease and lower serum tryptase levels should in particular have their bone density determined with treatment appropriate to the findings.

Absorptiometry, Photon↗
PubMed1997

Existence of c-kit receptor-positive, tryptase-negative, IgE-negative cells in human allergic nasal mucosa: a candidate for mast cell progenitor.

The accumulation of mast cells in the allergic nasal epithelium is well known, yet the mechanism remains unclear. We studied whether there is a candidate for mast cell progenitors in the allergic nasal mucosa tissue removed at the time of surgery. We first confirmed that most mast cells in nasal mucosae of 10 nasal allergic patients had c-kit receptor by immunohistochemistry using the mirror sectioning technique. We then investigated whether c-kit receptor+, tryptase-, IgE- cells existed in nasal mucosae of 15 nasal allergic patients and 15 nonallergic ones using sequential triple immunohistochemistry. We observed the area in which 1,000 to 1,100 tryptase-positive cells (mast cells) existed in both the subepithelial layer and the deep layer of each nasal lamina propria. The epithelial layer above this area was also examined. Some c-kit receptor+, tryptase- cells existed in the nasal mucosae of 11 patients with nasal allergy and of 5 patients with nonallergic rhinitis. From one to four of these cells in the nasal epithelium and subepithelial layer of the 4 allergic patients were IgE-negative. In contrast, no IgE-negative cells existed in the deep layer of allergic nasal mucosae or in any nonallergic nasal mucosae. Our results suggest that mast cell progenitors, hematopoietic progenitor cells or multipotential blood cells exist in the allergic nasal mucosa, and may contribute to the increase of mast cells in the epithelium and subepithelial layer of allergic nasal mucosa.

Adolescent↗
PubMed1998

Recombinant expression of human mast cell proteases chymase and tryptase.

Expression of recombinant human chymase and tryptase was achieved in a baculovirus-insect cell system using a fusion protein construct. Recombinant baculovirus was produced with DNA coding for a NH2-ubiquitin-chymase-COOH or NH2-ubiquitin-tryptase-COOH fusion protein inserted immediately downstream of the signal sequence for the secreted envelope protein, glycoprotein 67. In each construct, the natural prepropeptide sequence of the protease was replaced by the amino acid sequence for the enterokinase cleavage site of trypsinogen. High Five insect cells infected with either of the modified baculovirus produced mg quantities of each fusion protein per liter of culture. Treatment of the chymase-fusion protein with enterokinase or the tryptase-fusion protein with enterokinase in the presence of a highly charged polysaccharide (dextran sulfate or heparin) produced enzymatically active proteases with properties of the native enzymes. A procedure for the purification of mg quantities of recombinant chymase from infected-cell medium is presented.

Animals↗
PubMedDate not supplied

Eosinophil cationic protein (ECP) and tryptase in the nasal lavage fluid (NLF) of children with grass pollen rhinitis: levocabastine effect.

This study was carried out to determine the concentrations of eosinophil cationic protein (ECP) and tryptase in the nasal lavage fluid (NLF) of 24 children (C) with grass pollen rhinitis as well as rhinitis symptoms before and after nasal provocation tests with or without a levocabastine (anti-H1 topical antihistamine) pretreatment. All C were monosensitized to grasses only. Twelve patients (Active Group = AG) were tested with a nasal provocation test with grass pollen (NPT) carried out by the insufflation of increasingly higher doses of an allergenic extract powder, while the other 12 patients (Placebo Group = PG) underwent just a nasal provocation test with lactose (placebo) (NPTp). The prechallenge NLF, obtained both before (C) and after (AG) levocabastine pretreatment, was compared to that obtained after periods of 2 and 24 hours postchallenge. In the AG, before and after levocabastine pretreatment, the tryptase concentrations had not significantly increased, whereas the ECP concentrations were found to be significantly higher (p < 0.05) in just the 24-hour postchallenge samples. In the PG the rhinitis symptoms were not induced by the NPTp and there was no significant change in either ECP or tryptase concentrations. In the AG a levocabastine pretreatment induced a significant increase (p < 0.05) in the cumulative allergen doses administered by the NPT. There was a reduction of the nasal symptoms in 7 patients, while in 3 subjects there was only a slight improvement, but in 2 subjects no effect was encountered. In conclusion this study shows that a levocabastine pretreatment before an NPT in patients with grass pollen rhinitis, outside the grass pollen season, induces a significant increase in the cumulative allergen doses (administered by the NPT) which provoked rhinitis symptoms but is not able to demonstrate any significant reduction in the ECP concentrations of the NLF.

Blood Proteins↗
PubMed2000

Angiogenesis and mast cell density with tryptase activity increase simultaneously with pathological progression in B-cell non-Hodgkin's lymphomas.

Node biopsies of 16 benign lymphadenopathies and 72 B-cell non-Hodgkin's lymphomas (B-NHLs) were investigated for counts of microvessels, total metachromatic mast cells (MCs) and MCs expressing tryptase, an angiogenesis-inducing molecule. Counts were higher in B-NHLs. When grouped according to the Working Formulation (WF) malignancy grades, they were significantly higher in low-grade B-NHLs vs. lymphadenopathies and intermediate-grade vs. low-grade tumors and there was a further increase in the high-grade tumors. A high correlation was demonstrated in all groups of tissues between microvessel counts and both total metachromatic and tryptase-reactive MCs. These results suggest that angiogenesis in B-NHLs increases with their progression, and that MCs cooperate in its induction via the tryptase contained in their secretory granules.

Chymases↗
PubMed2001

Cetirizine reduces the number of tryptase-positive mast cells in psoriatic patients: a double-blind controlled study.

Psoriatic plaque contains an increased number of mast cells that are thought to play an important role in the initiation and maintenance of the disease through the release of mediators such as histamine, proteoglycans, proteinases and cytokines. To verify the possible participation of these cells in the chronic inflammatory cutaneous response in psoriasis, we performed a double-blind controlled study to investigate the presence and activation of tryptase-positive mast cells in the lesional skin of 19 patients affected by active psoriasis vulgaris minima compared with five healthy, age-matched subjects. Psoriatic patients were randomized into two groups (A and B). The first group was treated with cetirizine (10 mg/three times a day for 15 days) and the second one was treated with placebo. Both groups underwent clinical staging [psoriasis area and severity index (PASI) score] and immunohistochemical evaluation [alkaline phosphatase antialkaline phosphatase (APAAP) procedure] before and after treatment. In group A, the PASI score ranged from 3.8 (SE +/- 1.00) to 1.8 (SE +/- 0.68) and in group B, from 5.0 (SE +/- 0.98) to 3.4 (SE +/- 0.47). The mean number of tryptase-positive mast cells for field, mainly distributed in the perivascular and periadnexal sites, ranged from 40.8 (SE +/- 7.15) to 21.6 (SE +/- 3.04) in group A and from 25.1 (SE +/- 3.78) to 26.3 (SE +/- 3.59) in group B (ANOVA test f = 6.95; gl = 1.16; p = 0.02). In our psoriatic patients, cetirizine significantly reduced the expression of tryptase-positive mast cells and produced a clinical improvement in erythema, suggesting a multilevel immunopharmacologic modulation of this antihistamine in psoriasis.

Adult↗
PubMed2001

Serum tryptase analysis in a woman with amniotic fluid embolism. A case report.

BACKGROUND: Recent studies have noted a striking similarity between amniotic fluid embolism (AFE) and anaphylaxis. Serum tryptase levels may therefore serve as a marker of mast cell degranulation in AFE cases. CASE: A 40-year-old woman, gravida 6, para 4, experienced the acute onset of facial erythema, eclampsia-type seizures, severe hypoxia, cardiac arrest and disseminated intravascular coagulation while in early active labor. The patient was declared dead 37 minutes after the onset of resuscitative efforts. At autopsy, fetal squames were found within the pulmonary tree, uterine blood vessels and brain. A peripheral venous blood specimen, obtained approximately one and a half hours postmortem, revealed a tryptase level of 4.7 ng/mL (normal, < 1). CONCLUSION: An elevated serum tryptase level, in conjunction with our patient's clinical history, adds further supporting evidence to the concept of AFE as an anaphylactoid syndrome of pregnancy.

Adult↗
PubMed2001

[The changes of tryptase activity in anaphylactic shock guinea-pigs].

OBJECTIVE: To investigate the changes of the activity of tryptase of sera, lungs and bronchial tubes in the guinea-pigs which suffered from hetero-serum anaphylactic shock. METHODS: Sera and tissues were collected from anaphylactic shock guinea-pigs, and the enzyme activity was tested colormetrically using special substrate, BAPNA. RESULTS: The activity of tryptase of sera, lungs and bronchial tubes increased significantly in Anaphylactic guinea-pigs compared with control group. CONCLUSION: The changes of tryptase activity are helpful to diagnose anaphylactic shock.

Anaphylaxis↗