Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Asthma is characterized by the presence of an inflammatory cell infiltrate in the bronchial mucosa consisting of activated mast cells, eosinophils, and T cells. Several cytokines are considered to play a pivotal role in this response, particularly interleukin (IL)-4, IL-5, IL-6, and tumor necrosis factor-alpha (TNF-alpha). In this study, we have used immunohistochemistry applied to thin glycol methacrylate sections of bronchial mucosal biopsies to define the cellular provenance of these cytokines in normal and asthmatic airways. Both the asthmatic and normal mucosa contained numerous cells staining positively for all four cytokines, with the majority identified as mast cells by their tryptase content. Eosinophils also accounted for some IL-5 immunostaining in the asthmatic biopsies. By using two monoclonal antibodies directed to different epitopes of IL-4, we provide tentative evidence for enhanced IL-4 secretion in asthma. Similarly, a sevenfold increase in the number of mast cells staining for TNF-alpha in the asthmatic biopsies suggests that this cytokine is also up-regulated in this disease. These findings clearly identify human mast cells as a source of IL-4, IL-5, IL-6, and TNF-alpha and add to the view that, along with T cells, mast cells may play an important role in initiating and maintaining the inflammatory response in asthma.
Am J Respir Cell Mol Biol 1994 May
PMID:Interleukin-4, -5, and -6 and tumor necrosis factor-alpha in normal and asthmatic airways: evidence for the human mast cell as a source of these cytokines. 817 9

We have investigated the phenotype of interleukin-5 (IL-5) mRNA+ cells in the nasal mucosa of subjects with allergic rhinitis. Serial cryostat sections were cut from paraformaldehyde-fixed snap-frozen nasal biopsies from six patients, before and 24 h after local allergen provocation with grass pollen. Immunocytochemistry (APAAP) was followed by in situ hybridization on the same sections. For immunocytochemistry, antibodies against CD3, tryptase, and major basic protein (MBP) were used to identify T cells, mast cells, and eosinophils, respectively. Hybridization studies were performed using a Digoxigenin-labeled IL-5 riboprobe. Nitroblue tetrazolium (NBT) and X-phosphate-5-bromo-4-chloro-3- indoly phosphate (BCIP) served as chromogens to detect hybridized IL-5 mRNA signals. The majority of IL-5 mRNA+ cells were CD3+ (83.2%), whereas the remainder were either tryptase+ (11.3%) or MBP+ (5.4%). In contrast, only a few IL-5 mRNA+ cells were observed in nasal biopsies before challenge, all of which were co-localized to CD3+ cells. These results indicate that CD3+ cells are the principal cellular source of IL-5 transcripts in the nasal mucosa 24 h after allergen-induced late-phase nasal responses.
Am J Respir Cell Mol Biol 1993 Oct
PMID:T cells are the principal source of interleukin-5 mRNA in allergen-induced rhinitis. 839 74

Cytotoxic lymphocytes and natural killer cells are able to kill their target cells in minutes. The death of the target cell occurs after the release of cytoplasmic granules from the effector cell. These granules contain the pore-forming protein perforin and serine proteases (granzymes). To date 10 genes encoding lymphocyte granzymes have been discovered; of these only four have been purified and characterized for their substrate specificity. Several are predicted to have a common chymase, like specificity which is found in the granule extracts. Others may need to be enriched as active enzymes before they can be evaluated for substrate hydrolysis. Due to the limitations of detection by substrate hydrolysis, a more sensitive method for the detection of dilute granules was needed. We report the differing reactivities of seven biotin (Bi)-tagged isocoumarin (IC) inhibitors for Asp-ase, chymase, tryptase and Met-ase granzymes. The inhibitors contained different substituents at their no. 3 position: methoxy (OMe), ethoxy (OEt), propoxy (OPr) or 2-phenylethoxy (OEtPh) groups. The OMe group conferred general reactivity, whereas the OEtPh group conferred selective reactivity with chymase granzymes. The inhibitors that contained the longest aminocaproyl (Aca) spacers between the biotin-tag and the isocoumarin ring mediated the most stable granzyme inactivation. These inhibitors were the most effective at blocking lysis of red blood cells by the granule extracts. The inhibitors were used in protein blotting experiments where the biotin was detected with an avidin-enzyme complex. Over 10 granzymes were labelled by the inhibitor Bi-Aca-Aca-IC-OMe. The inhibitors detected granzymes when they were not readily detected by substrate hydrolysis.
Mol Immunol
PMID:Characterization, application and potential uses of biotin-tagged inhibitors for lymphocyte serine proteases (granzymes). 876 Feb 73

The growth and differentiation of mast cells are regulated by cytokines produced in tissue microenvironments. We previously reported that mast cells isolated from the epithelial compartment of nasal polyp tissue contain significantly less tryptase when compared with mast cells isolated from the stroma of the same tissue. In an attempt to explore this finding, we analyzed the ability of supernatants obtained from cultured nasal polyp epithelial cells (NP-EpCM) or nasal polyp fibroblasts (NP-FbCM) to regulate the tryptase content of the immature human mast cell line HMC-1. HMC-1 cells were cultured for 7 days in Iscove's modified Dulbecco's medium (IMDM) with 30% of either NP-FbCM or NP-EpCM or 20% MoCM (supernatant of a leukemic T cell line). As assessed by radioimmunoassay and test for enzymatic activity, all three conditioned media were shown to significantly decrease tryptase protein expression in HMC-1, when compared with cultures performed with IMDM alone (NP-EpCM P < 0.001; NP-FbCM P < 0.04; MoCM P < 0.004). In addition, Northern blot analysis demonstrated lower tryptase mRNA levels upon exposure to all three conditioned media tested, suggesting that tryptase downregulation occurs at the transcriptional level. In further studies we found that preincubation of MoCM with anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) completely blocked the observed downregulation of tryptase expression mediated by this conditioned medium. The findings suggest that GM-CSF has a suppressive effect on expression of protease in mast cells, and may thus play a modulatory role in determining the extent of tissue inflammation in allergic airways disease.
Am J Respir Cell Mol Biol 1996 Sep
PMID:Specific inhibition of beta-tryptase expression in a human mast cell line by granulocyte-macrophage colony-stimulating factor produced by airways structural cells. 881 Jun 39

Exercised mdx mice were used to evaluate the efficacy of two pharmacologic entities, cromolyn and compound 48/80. Beginning at 2 weeks of age, mdx mice were treated with either cromolyn (50 mg/kg/day), prednisone (2mg/kg/day), compound 48/80 (1mg/kg/day), or diluent vehicle. At 4 weeks of age, treated mice were subjected to twice weekly, forced treadmill running which has previously been shown to cause expressed weakness in mdx mice (Hudecki, Pollina et al., 1993). Strength was evaluated weekly through 6 weeks of age using a previously described "pull-test" procedure (Hudecki, Pollina et al., 1993). Serum creatine kinase (CK) and mast cell tryptase activities were evaluated from 6 week blood samples. There was a significant increase in strength in mdx mice treated with cromolyn (p < or = 0.05), while no significant increase in strength was found in mice treated with compound 48/80, or prednisone compared to vehicle controls. While no significant change in tryptase activity was found between treatments, CK activity was significantly increased in the cromolyn group compared to vehicle controls. However, when tryptase and CK were expressed as a combined factor (Tryp x CK), the cromolyn treated group was significantly different from all other groups. The results of this study suggest a possible use for cromolyn-like compounds in the treatment of Duchenne muscular dystrophy.
Res Commun Mol Pathol Pharmacol 1996 Mar
PMID:Cromolyn increases strength in exercised mdx mice. 882 68

The allergen-induced late nasal response (LNR) is associated with high expression of interleukin-4 (IL-4) and IL-5 messenger RNA (mRNA) in the nasal mucosa, suggesting a role for Th2-type cytokines in the development of the LNR. Moreover, topical corticosteroid-mediated inhibition of the LNR is accompanied by inhibition of IL-4, but not IL-5, mRNA expression, IL-13 shares a number of functions with IL-4, including IgE switching and vascular cell adhesion molecule-1 (VCAM-1) upregulation. We investigated the expression of IL-13 mRNA and immunoreactivity in nasal biopsies from 10 normal subjects and 20 subjects with allergic rhinitis. IL-4 mRNA expression was examined in the same subjects. The allergic rhinitis patients were randomized to receive a 6-wk treatment with either topical fluticasone propionate (n = 10) or placebo (n = 10) nasal spray twice daily. A nasal biopsy was taken before treatment and 24 h after local nasal allergen provocation with a grass-pollen extract. Before treatment, there was no significant difference between the allergic rhinitis patients and controls in the expression of IL-13 mRNA and immunoreactivity. After allergen provocation, we observed a significant increase in IL-13 mRNA-positive and immunoreactive cells at 24 h only in subjects given placebo (P < 0.001). Inhibition of the LNR after corticosteroid treatment was associated with a marked decrease in allergen-induced IL-13 mRNA-positive (P < 0.001) and immunoreactive cells (P < 0.001). In subjects given placebo, 76.9 +/- 5.5% of IL-13 mRNA-positive cells observed after allergen were CD3+, whereas 11.2 +/- 2.7% coexpressed immunoreactivity for mast-cell tryptase. In these subjects, increases in cells expressing IL-13 mRNA were greater than for IL-4 mRNA (P = 0.001), and double in situ hybridization studies revealed that 100% of the IL-4 mRNA-positive cells coexpressed IL-13 mRNA, whereas 66.6 +/- 10.5% of IL-13 mRNA-positive cells coexpressed IL-4 transcripts after allergen challenge. The results of this study suggest that IL-13 expression is a prominent feature of the LNR, and that inhibition of the LNR following steroid therapy may be partly attributable to inhibition of IL-13 expression.
Am J Respir Cell Mol Biol 1997 Jul
PMID:IL-13 mRNA and immunoreactivity in allergen-induced rhinitis: comparison with IL-4 expression and modulation by topical glucocorticoid therapy. 922 5

Some structural features of bovine tryptase were discussed based on spectroscopic analysis. The far UV-CD spectrum of the enzymatically active bovine tryptase is consistent with a structure containing very little, if any alpha-helix, as found for other serine proteases. The analysis of near UV-CD and UV absorption spectra reveals the presence of a high number of Trp residues arranged probably in strong structural motifs. At variance with other tryptases, the bovine enzyme shows an electrophoretic behaviour in native and denaturating conditions compatible with an association state larger than a tetramer (probably a dodecamer). From a biochemical point of view, the bovine tryptase shares with the human counterpart, the preference for cleaving substrates bearing dibasic cleavage sites. Thus, it is hypothesized that tryptase may be involved in some proprotein processing mechanism(s).
Comp Biochem Physiol B Biochem Mol Biol 1998 Jun
PMID:Structural and functional properties of Bos taurus tryptase: a search for a possible propeptide processing role. 978 93

Human chymase (HC) is a chymotrypsin-like serine proteinase expressed by mast cells. The 2.2 A crystal structure of HC complexed to the peptidyl inhibitor, succinyl-Ala-Ala-Pro-Phe-chloromethylketone (CMK), was solved and refined to a crystallographic R-factor of 18.4 %. The HC structure exhibits the typical folding pattern of a chymotrypsin-like serine proteinase, and shows particularly similarity to rat chymase 2 (rat mast cell proteinase II) and human cathepsin G. The peptidyl-CMK inhibitor is covalently bound to the active-site residues Ser195 and His57; the peptidyl moiety juxtaposes the S1 entrance frame segment 214-217 by forming a short antiparallel beta-sheet. HC is a highly efficient angiotensin-converting enzyme. Modeling of the chymase-angiotensin I interaction guided by the geometry of the bound chloromethylketone inhibitor indicates that the extended substrate binding site contains features that may generate the dipeptidyl carboxypeptidase-like activity needed for efficient cleavage and activation of the hormone. The C-terminal carboxylate group of angiotensin I docked into the active-site cleft, with the last two residues extending beyond the active site, is perfectly localized to make a favorable hydrogen bond and salt bridge with the amide nitrogen of the Lys40-Phe41 peptide bond and with the epsilon-ammonium group of the Lys40 side-chain. This amide positioning is unique to the chymase-related proteinases, and only chymases from primates possess a Lys residue at position 40. Thus, the structure conveniently explains the preferred conversion of angiotensin I to angiotensin II by human chymase.
J Mol Biol 1999 Feb 12
PMID:The 2.2 A crystal structure of human chymase in complex with succinyl-Ala-Ala-Pro-Phe-chloromethylketone: structural explanation for its dipeptidyl carboxypeptidase specificity. 993 Dec 57

It has been proposed that the pathogenicity of the influenza and Sendai virus is primarily determined by host cellular proteases that activate viral infectivity. We isolated trypsin-type serine proteases from rat lungs, candidates for the processing proteases of viral envelope glycoproteins, such as tryptase Clara localized in the Clara cells of the bronchial epithelium and mini-plasmin. These enzymes specifically cleave the precursor of fusion glycoprotein HA of influenza virus at Arg325, and the F0 of Sendai virus at Arg116 in the consensus cleavage motif, Gln(Glu)-X-Arg, resulting in the induction of infectivity of these viruses. Proteolytic activation of viruses by these enzymes occurs extracellularly, probably on the surface and/or in the lumen of the respiratory tract. On the other hand, we isolated two compounds from human bronchial lavage, which inhibit the activity of tryptase Clara. One was a mucus protease inhibitor and the other was a pulmonary surfactant. These compounds inhibited multiple cycles of virus replication in vitro and in vivo, but did not themselves affect the hemagglutination and the infectivity of the virus. Administration of these compounds in the airway may be useful for preventing and treating infection with influenza virus and Sendai virus.
Mol Cells 1999 Jun 30
PMID:Cellular proteinases trigger the infectivity of the influenza A and Sendai viruses. 1042 Sep 80

Mast cells play a potentially important role in fibroproliferative diseases, releasing mediators including tryptase that are capable of stimulating fibroblast proliferation and procollagen synthesis. The mechanism by which tryptase stimulates fibroblast proliferation is unclear, although recent studies suggest it can activate protease-activated receptor (PAR)-2. We therefore investigated the role of PAR-2 in tryptase-induced proliferation of human fetal lung and adult lung parenchymal and airway fibroblasts and, for comparative purposes, adult dermal fibroblasts. Tryptase (0.7-70 mU/ml) induced concentration-dependent increases in proliferation of all fibroblasts studied. Antipain, bis(5-amidino-2-benzimidazolyl)methane, and benzamidine inhibited tryptase-induced fibroblast proliferation, demonstrating that proteolytic activity is required for the proliferative effects of tryptase. RT-PCR demonstrated the presence of PAR-2 mRNA, and immunohistochemical staining localized PAR-2 to the cell surface of lung fibroblasts. In addition, specific PAR-2 activating peptides, SLIGKV and SLIGRL, mimicked the proliferative effects of tryptase. In contrast, human dermal fibroblasts only weakly stained with the PAR-2 antibody, PAR-2 mRNA was almost undetectable, and fibroblasts did not respond to PAR-2 activating peptides. These results suggest that tryptase induces lung, but not dermal, fibroblast proliferation via activation of PAR-2 and are consistent with the hypothesis that the release of tryptase from activated mast cells may play an important role in the fibroproliferative response observed in asthma, chronic obstructive pulmonary disease, and patients with pulmonary fibrosis.
Am J Physiol Lung Cell Mol Physiol 2000 Jan
PMID:Mast cell tryptase stimulates human lung fibroblast proliferation via protease-activated receptor-2. 1064 7


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>