Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Supernatants from PHA-activated human peripheral blood mononuclear cells, depleted of virtually all IL-2 activity by an anti-rIL-2 immunoadsorbent column, contain a factor(s) which synergizes with rIL-2 in facilitating the generation of allogeneic human CTL responses in vitro. This factor, provisionally termed CTL maturation factor (TcMF), did not appear to promote CTL responses in the absence of rIL-2. Furthermore, it acted later than IL-2 in facilitating CTL responses and could not be replaced by recombinant IFN-gamma. In this report we show that rIFN-alpha, rIL-1 alpha, and rIL-1 beta likewise lack TcMF activity. The TcMF activity in lymphokine-containing culture supernatants could be eliminated by trypsin or pronase but not by neuraminidase or RNase. Gel filtration revealed two peaks of TcMF activity, one at 12,000 to 25,000 Da and the other at 45,000 to 65,000 Da. Isoelectrofocusing demonstrated substantial charge heterogeneity. The majority of TcMF activity was recovered between pI 4.0 and pI 5.5 with a minor component at pI 6.5, corresponding to the areas in which IL-1 activity was also found. However, TcMF activity could be separated from IL-1 by reverse-phase HPLC. Moreover, TcMF recovered following reverse-phase HPLC was also found to be depleted of IL-4 activity. These studies suggest that TcMF activity is mediated by a protein(s) distinct from IL-1, IL-2, IL-4, and interferon-alpha or-gamma.
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PMID:Characterization of a factor(s) which synergizes with recombinant interleukin 2 in promoting allogeneic human cytolytic T-lymphocyte responses in vitro. 327 3

PF-382 is a human T-cell line that has been shown to elaborate factors that modulate normal hemopoiesis in vitro. In the present study we report that this cell line constitutively releases in both serum-containing and serum-free supernatants a potent enhancer of BFU-E growth. The factor(s), partially purified by gel filtration, is a heat-stable molecule(s) degradable by trypsin and 2-mercaptoethanol treatments, equally active on bone marrow and peripheral blood erythroid progenitor cells, but not on CFU-GM. Unlike other sources of BPA, this stimulatory factor(s) exerts its effect in the presence of mononuclear adherent cells. In fact, the addition of conditioned medium obtained by 48 hr preincubation of isolated monocytes with 10% PF-382 supernatant (M-CM2) or the concomitant addition of supernatant from PF-382 cells (PF-382-CM) and from unstimulated monocytes (M-CM1) are capable of fully replacing the presence of monocytes in the BFU-E assay. Since the independent addition of PF-382-CM or of M-CM1 is devoid of stimulatory function, we suggest that the PF-382 derived BFU-E growth inducer, which differs from IL-1, IL-3, IL-4, GM and G-CSF, exerts its activity "via" a synergistic mechanism with a monokine.
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PMID:Soluble factor(s) released by the PF-382 T-cell line enhances the stimulatory effect of monocytes on the BFU-E growth. 328 87

In murines, interleukins (IL) 3, 4, 9, and 10, nerve growth factor, and stem cell factor induce or promote growth and differentiation of mast cells (MC). Increased stimulation and synergy was observed when combinations of cytokines were used. In man, no growth factor for human MCs had been identified until recently, when SCF was found to induce in vitro growth and differentiation of human MCs. In the present study, the effects of recombinant human IL-3 and IL-4 on SCF-dependent differentiation of human MCs from their circulating progenitor cells in long-term culture were analyzed. Surprisingly, both IL-3 and IL-4 were found to inhibit SCF-dependent formation of human MCs (SCF, 100 ng/ml: 36.4 +/- 18.7 x 10(3)/ml; SCF + IL-3, 100 U/ml: 23.4 +/- 4.2 x 10(3)/ml; SCF + IL-4, 100 U/ml: 7.4 +/- 4.4 x 10(3)/ml) and synthesis of MC tryptase (SCF, 100 ng/ml: 73.2 +/- 17.6 ng/ml; SCF + IL-3, 100 U/ml: 10.8 +/- 3.1 ng/ml [p < 0.01]; SCF + IL-4, 100 U/ml: 8.1 +/- 1.5 ng/ml, [p = 0.02]). The inhibitory effects of these cytokines on SCF-dependent formation of human MCs were associated with an increase in the number of macrophages (IL-3) or lymphocytes (IL-4) in the same cultures and may be due to competitive recruitment of cells from a pool of multilineage hematopoietic progenitor cells.
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PMID:Inhibition of stem cell factor dependent formation of human mast cells by interleukin-3 and interleukin-4. 752 90

Human mast cells can be divided into two distinct phenotypes based on their content of neutral serine proteases, suggesting that they serve differing biologic and pathologic roles. Recently, it has been demonstrated that human mast cells are a source of several pleiotropic cytokines including IL-4, IL-5, IL-6, IL-8, and TNF-alpha, but not all mast cells contain all of these cytokines, suggesting that there is also functional heterogeneity with respect to cytokine expression. In this study, we have examined the relationship between mast cell neutral protease expression and cytokine content using immunohistochemistry. Bronchial mucosal biopsies from five normal subjects and five patients with allergic asthma, and nasal mucosal biopsies from five normal subjects and three patients with allergic rhinitis were embedded in glycol methacrylate. Sections (2 microns) were stained for IL-4, IL-5, and IL-6, adjacent to serial sections stained for tryptase and chymase. The distribution of cytokines among the tryptase+ chymase- mast cells (MCT) and tryptase+ chymase+ mast cells (MCTC) was examined by co-localization of cytokines to MCTC or MCT in serial sections using the camera-lucida. Although IL-4 was distributed among both mast cell phenotypes, it was expressed preferentially by the MCTC subset (overall 85% MCTC:15% MCT). In contrast, IL-5 and IL-6 were restricted almost exclusively to the MCT subset. Immunostaining of isolated skin mast cells (> 99% MCTC) supported these findings, with strong immunoreactivity present for IL-4 but very little for IL-5 or IL-6. These results indicate that in addition to exhibiting heterogeneity with respect to neutral protease content of the secretory granules, human mast cells are also heterogeneous with respect to cytokine content. This suggests that the biologic functions of MCTC and MCT cells differ as a result of their capacity to generate and release different cytokine profiles.
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PMID:Heterogeneity of human mast cells based on cytokine content. 760 7

We have investigated the phenotype of cells positive for IL-4 and IL-5 mRNA in the nasal mucosa of subjects with allergic rhinitis and in bronchoalveolar lavage and bronchial biopsies from atopic asthmatic subjects. The method employed was immunochemistry followed by in situ hybridization using either 35S- or digoxigenin-labelled riboprobes. With nasal and bronchial tissue, this double ICC/ISH method revealed that more than 70% of IL-4 and IL-5 mRNA+ cells were T cells. The remaining IL-4 and IL-5 signals were co-localized to tryptase-positive mast cells and EG2+ eosinophils. Occasional IL-4 and IL-5 mRNA cells were observed in non-asthmatic control subjects, the large majority being CD3+ cells. These results indicate that CD3+ cells are the principal cellular source of IL-4 and IL-5 transcripts in atopic asthma and allergic rhinitis.
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PMID:Phenotype of cells positive for interleukin-4 and interleukin-5 mRNA in allergic tissue reactions. 761 32

Clinical studies of vernal keratoconjunctivitis (VKC) patients show that total IgE serum levels are increased even in the absence of IgE antibodies to common allergens. Activated eosinophils are also a constant feature of VKC at both the circulation (cytofluorimetry) and tissue (tear cytology and conjunctival scrapings) levels. Moreover, allergen challenge induces a prolonged inflammatory reaction with a prevalent participation of eosinophils, lymphocytes and possibly basophils. Immunohistochemical studies of VKC biopsies show a multicellular inflammatory infiltrate with prevalence of activated eosinophils, mast cells and CD4 lymphocytes in both epithelium and subepithelium. Mediator studies indicate that eosinophil products (eosinophil peroxidase, eosinophinal cationic protein and eosinophil-derived neurotoxin/eosinophil protein X) are increased in both serum and tears, where tryptase and interleukin (IL)-5 are also detectable in higher amounts than in controls. On the basis of these findings, we postulate that VKC can represent a phenotypic model of up-regulation of the cytokine gene cluster on chromosome 5q which through its products (IL-3, IL-4, IL-5 and granulocyte/macrophage-colony-stimulating factor) regulates Th2 prevalence, IgE production as well as mast cell and eosinophil growth and function in VKC.
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PMID:Vernal keratoconjunctivitis: a model of 5q cytokine gene cluster disease. 761 25

Recently, authors have addressed the ability of human basophils to produce IL-4. We report here the detection of significant serum IL-4 levels in a case of acute transformation of chronic myelogenous leukemia with a predominant basophilic cell population. Leukemic basophils were isolated from patients' PBMC and assayed for their IL-4-mRNA expression and their ability to secrete this cytokine in vitro. Leukemic basophilic cells (> 90% toluidine blue positive) but not other PBMC expressed IL-4-mRNA, contained IL-4 protein, and secreted this cytokine. These cells had a spontaneous IL-4 secretion ability, without a need for an exogenous activator. Meanwhile, IL-4 release was significantly increased following leukemic cell activation through Fc epsilon RI-ligation or by Ca2+ ionophore. IL-4 and its mRNA were also detected in leukemic basophils from three other chronic myelogenous leukemia patients with moderate basophilia (13, 14, and 23% basophils in PBMC). To confirm these data in normal human cells, we have developed a method to obtain large numbers of purified basophils from human bone marrow cell cultures. In contrast to leukemic basophils, normal cells required in vitro activation through Fc epsilon RI ligation or by Ca2+ ionophore to express and secrete IL-4. Leukemic and normal basophils secreted histamine following in vitro activation, but were negative for tryptase. These data thus demonstrate the in vivo and in vitro ability of human basophils to produce IL-4.
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PMID:IL-4 release by human leukemic and activated normal basophils. 768 30

The recently cloned interleukin 13 (IL-13) shares most investigated biological activities on B lymphocytes and monocytes with IL-4. In this study we investigated the potential role of IL-13 in regulating human mast cell activities. The effects of IL-13 on the expression of an immediate-early response gene (c-fos), proliferation, expression of mast cell-associated cell surface antigen (CD54 and Kit), and in vitro differentiation of human mast cells, were investigated. We compared the effect of IL-13 with that of IL-4. Both IL-13 and IL-4 induced expression of c-fos in cells from the human mast cell line HMC-1. This indicates that mast cells express functional receptors for IL-13. IL-13 and IL-4 decreased the proliferation rate of HMC-1 cells. However, IL-13 was less potent than IL-4. Human mast cells constitutively express the adhesion molecule ICAM-1 (CD54) and the receptor for stem cell factor (Kit) (CD117). The expression of CD54 was increased after treatment with IL-13 or IL-4, whereas the expression of Kit was decreased. Also in this action IL-4 was more potent than IL-13. By culturing mononuclear cells from cord blood in the presence of stem cell factor there is a differentiation of tryptase-positive mast cells in the cultures. This process was inhibited when IL-4 was present. In contrast, IL-13 did not affect the expression of tryptase during differentiation of stem cell factor dependent cord blood-derived mast cells. Taken together, these findings indicate that IL-13 has regulatory effects on human mast cells. The effect overlaps with but is also different from that of IL-4.
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PMID:Effects of interleukin (IL)-13 on immediate-early response gene expression, phenotype and differentiation of human mast cells. Comparison with IL-4. 770 21

Several reports have shown the presence of T-helper lymphocytes with Th2 characteristics in the skin lesions of atopic dermatitis (AD). However, Th2 cells themselves require an exogenous pulse of IL-4 to initiate their differentiation and synthesis of IL-4. As mast cells have recently been shown to contain IL-4, this finding prompted us to investigate IL-4 in mast cells of AD lesions, to determine if they might provide the IL-4 pulse needed by the Th2 cells. In this study, we measured IL-4 immunoreactivity in mast cells of non-lesional and lesional skin sections from 20 patients with AD. Ten patients with nummular eczema (NE) without any atopic features or background, and five healthy subjects, served as the control groups. Mast cells were first identified using an enzyme--histochemical staining method for tryptase. Subsequently, the sections were photographed, the tryptase stain was removed, and IL-4 was demonstrated with a polyclonal antibody. The sections were photographed again, and the percentage of IL-4 positive mast cells was calculated. The percentage of mast cells exhibiting IL-4 immunoreactivity in the upper dermis in lesional vs. non-lesional skin was 66 +/- 18% vs. 37 +/- 18% in AD (P < 0.0001, paired t-test), but only 46 +/- 19% vs. 31 +/- 22% in NE. In the skin of healthy controls, only 23 +/- 25% of the mast cells were positive for IL-4. In addition, a significant difference was found between lesional skin of AD vs. NE patients (P < 0.008, unpaired t-test).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Mast cells are one major source of interleukin-4 in atopic dermatitis. 791 8

The supernatant of a cell line of squamous cell carcinoma of the head and neck (SCCHN), PCI-50, was previously shown to induce activation, promote proliferation and increase antitumor cytotoxicity of freshly purified human natural killer (NK) cells and CD4+ T lymphocytes [Arch Otolaryngol Head Neck Surg (1994) in press]. This supernatant was found also to promote the growth of a variety of hematopoietic cell lines, including Jurkat, THP-1, K562, NK-92 or Epstein-Barr-virus-transformed B cell lines. The Jurkat cell line was selected as a reporter cell in an 18-h proliferation assay established to measure the growth-promoting activity of PCI-50 supernatant. The presence of soluble tumor-derived factors able to induce proliferation of Jurkat cells was demonstrated in the supernatant produced by several other SCCHN cell lines but not in that produced by a gastric cancer cell line (HR) or renal cell carcinoma line (5117G8). The growth-promoting PCI-50 supernatant was shown to contain 28 +/- 0.5 pg/ml interleukin-6 (IL-6) in vitro but was negative for interferon gamma, IL-1, IL-2, IL-4, tumor necrosis factor alpha, granulocyte/macrophage-colony-stimulating factor and IL-12. The addition of any of these recombinant cytokines to Jurkat cell cultures did not significantly promote growth, while PCI-50 supernatant was consistently growth-stimulatory. This supernatant neither enhanced intracellular Ca2+ concentration in Jurkat cells nor induced up-regulation of activation antigens on the cell surface, although it supported growth of Jurkat cells in the absence of IL-2. The growth-promoting activity in the PCI-50 supernatant was acid-labile at pH 2 for 4 h, heat-resistant at 96 degrees C for 1 h and sensitive to treatments with trypsin and pepsin. Preincubation of the PCI-50 producer cells with tunicamycin or cyclohexamide reduced the level of growth-promoting activity in the supernatant. A partial purification of this activity was achieved using Amicon filtration, chromatography on concanavalin-A-Sepharose and then a hydroxyapatite column and high-pressure liquid chromatography gel filtration. The partially purified glycoprotein had a molecular mass of 50-70 kDa, as determined by gel filtration.
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PMID:Proliferation of hematopoietic cell lines induced by a soluble factor derived from human squamous cell carcinomas of the head and neck. 800 Oct 29


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