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1.
Summary The influence of transforming growth factor- (TGF-) on hematopoiesis has been evaluated by adding blocking antibodies against TGF- to colony forming assays (CFU-c). When optimum concentrations of recombinant growth factors, granulocyte-macrophage colony stimulating factor (GM-CSF), and interleukin-3 (IL-3) were added to stem cells from the peripheral blood of healthy individuals and certain patients with tumors or HIV infection, the anti-TGF- capable of blocking 5 ng/ml of active TGF- had no significant influence on erythroid or myeloid colony formation. However, in certain immunosuppressed individuals, anti-TGF- resulted in a significant decrease of erythroid colony formation and slight suppression of myeloid colony formation. The significant inhibition of hematopoiesis by plasma of HIV patients could be due to the presence of active forms of TGF-. The results of the blocking experiments are consistent with the concept that TGF- in low concentrations is essential for erythropoiesis and myelopoiesis but that higher levels of TGF- primarily inhibit erythropoiesis in vitro. TGF- serves as a coordinating factor when efficient recruitment of granulocytes and monocytes is more essential than erythropoiesis and stem cell growth.Abbreviations BFU-E burst forming unit-erythroid - CFC colony forming cells - CFU-GEMM colony forming unit-granulocyte/erythroid/macrophage/megacaryocyte - CFU-GM colony forming unit-granulocyte/macrophage - EPO erythropoietin - GM-CSF granulocyte/macrophage-colony stimulating factor - HIV human immunodeficiency virus - IL-1 interleukin-1 - IL-3 interleukin-3 - IMDM Iscove's Modified Dulbecco's medium - PBS phosphate buffered saline - TGF- transforming growth factor- - TNF- tumor necrosis factor-  相似文献   

2.
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGF- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFLF) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TGF-1, -2, or -3. Post-culture media were collected for ELISA assays of TGF-1, -2, and -3 . TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TFG-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and TGF-2 production and reduced expression of the up-regulated TGF-1 and TGF-2 mRNA induced by exogenous TGF-1, -2, or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   

3.
Mechanisms that regulate cytokine-mediated inflammation in the lungs of preterm infants, including factors which regulate production of the chemokine IL-8, remain poorly defined. Sequential bronchoalveolar lavage samples were obtained from preterm newborns with hyaline membrane disease over a 28-day period. Bronchoalveolar lavage cell cytokine relationships were evaluated and the differential regulation of IL-8 by IL-1 and TNF was studied in a short-term culture system. In vivo, IL-8 and IL-l protein levels correlated closely with each other and with macrophage counts. In cell culture, exogenous anti-IL-1 antibody led to a 40% maximum inhibition (approximately) of IL-8 production by lipopolysaccharide stimulated lung inflammatory cells. Comparable amounts of exogenous anti-TNF antibodies achieved a 15% maximum inhibition (approximately) of IL-8 production. Anti-IL-1 and anti-TNF antibodies in combination did not inhibit IL-8 production beyond that achieved by anti-IL-l antibody alone. These results, in preterm newborns, support the concept of lung inflammation mediated in part by a macrophage, IL-1, and IL-8 cell cytokine pathway. The results also suggest that factors other than IL-1 and TNF regulate IL-8 expression in the lungs of preterm infants.  相似文献   

4.
The convulsant properties of methyl -carboline-3-carboxylate (-CCM) were evaluated in the TaT-fm/Gnc Ta+/+Tfm strain carrying the tabby coat color (Ta) and/or the testicular feminization (Tfm) gene. When injected intraperitoneally within a 5–60 mg/kg dose range, -CCM-induced convulsions in less than 25% of the mice, thus providing evidence for a high resistance of this strain, as compared to classical strains of mice. However, this strain responds normally to the convulsant pentylenetetrazol (PTZ), suggesting a specific resistance to -CCM. Both the Ta gene and the TaTfm/Gnc genetic background were involved in the high resistance to -CCM. In addition, concentrations of neurosteroids and benzodiazepine binding, both modulating GABAA receptor efficacy, have been measured in order to elucidate the biological mechanisms of drug resistance.  相似文献   

5.
The level of bioactive transforming growth factor- (TGF-) was measured in serum from patients with chronic fatigue syndrome (CFS), healthy control subjects, and patients with major depression, systemic lupus erythematosis (SLE), and multiple sclerosis (MS) of both the relapsing/remitting (R/R) and the chronic progressive (CP) types. Patients with CFS had significantly higher levels of bioactive TGF- levels compared to the healthy control, major depression, SLE, R/R MS, and CP MS groups (P < 0.01). Additionally, no significant differences were found between the healthy control subjects and any of the disease comparison groups. The current finding that TGF- is significantly elevated among patients with CFS supports the findings of two previous studies examining smaller numbers of CFS patients. In conclusion, TGF- levels were significantly higher in CFS patients compared to patients with various diseases known to be associated with immunologic abnormalities and/or pathologic fatigue. These findings raise interesting questions about the possible role of TGF- in the pathogenesis of CFS.  相似文献   

6.
The expression of the 1 integrins was examined immunohistochemically in synoviocytes from normal synovial membrane and from chronic synovitis of different aetiology and intensity. Normal synoviocytes were 61-positive but lacked 1 through 5. In mild inflammation type A synoviocytes neo-expressed 1, 3, and 5 chains. In severe inflammation both type A and B synoviocytes expressed 3, 4, 5, and 6 chains. The effects of inflammatory cytokines, as single agents or in combination, on the 1 integrin expression in cultured normal synoviocytes was determined by immunocytochemistry and flow cytometry. The 1 chain, while absent in unstimulated synoviocytes, was induced by interleukin-1 (IL-1), tumour necrosis factor- (TNF-), and interferon- (INF-). This effect was enhanced by combining IL-1 and TNF-. Expression of the 3 chain was up-regulated by IL-1 and, more intensely, by IFN-. Transforming growth factor (TGF-) inhibited the up-regulating effect of IL-1 and antagonized the effect of IFN- on 3 chain expression. Expression of the 5 chain was up-regulated significantly by co-stimulation through IL-1 together with TGF- or TNF-. Thus, the 1 integrin profile of cytokine activated synoviocytes in vitro resembled that of synoviocytes in synovitis in situ. These data suggest that IL-1, TNF-, IFN-, and TGF- are likely to be among the effectors regulating 1 integrin expression in synoviocytes in vivo.  相似文献   

7.
Ten cases of primary gastric malignant lymphoma (PGL) were investigated by immunohistochemical and molecular genetic analysis. These cases were diagnosed histopathologically as follicular small cleaved cell type (1 case), diffuse small cleaved cell type (3 cases) and diffuse large cell type (6 cases) based on the WF (Working Formulation) classification. Seven cases classified as small cleaved or diffuse large cell type belong to low (4 cases) or high (3 cases) grade MALT lymphoma according to Isaacson's classification. All PGL belonged to B lineage cells according to immunohistochemical study and immunoglobulin rearrangements. Rearrangements of TCR chain genes were observed in four of the ten cases. The possibility that the TCR rearrangements were caused by tumour-infiltrating T-cells (TILs) was supported by the following observations: the tumours did not show T- and B-cell biphenotype, TCR exhibited functional VDJ rearrangement and V usage pattern was not a neoplastic type. Analysis of the repertoire of the TCR chain in TILs revealed a common usage of V2 in the above four cases, and furthermore, predominant usage of a particular chain composed of V2-D2.1-J2.3 was observed in one of the four cases. These results indicate that the TILs of PGL have a restricted TCR repertoire.  相似文献   

8.
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun.  相似文献   

9.
Cardiac sodium channels (Nav1.5) comprise a pore-forming -subunit and auxiliary -subunits that modulate channel function. In the heart, 1 is expressed throughout the atria and ventricles, whilst 3 is present only in the ventricles and Purkinje fibers. In view of this expression pattern, we determined the effects of 3 and 1 co-expression alone, and in combination, on Nav1.5 stably expressed in Chinese hamster ovary cells. The current/voltage relationship was shifted –5 mV with either 1 or 3 co-expression alone and –10 mV with co-expression of both 1 and 3. In addition, 3 and 1/3 co-expression accelerated macroscopic current decay. There were significant hyperpolarizing shifts in equilibrium gating relationships with co-expression of 1 and 3 alone and in combination. Co-expression of 1/3 together resulted in a greater hyperpolarizing shift in channel availability, and an increase in the slopes of equilibrium gating relationships. Co-expression of 3 and 1/3, but not 1, slowed recovery from inactivation at –90 mV. Development of inactivation at –70 and –50 mV was accelerated by -subunit co-expression alone and in combination. -Subunit co-expression also reduced the late Na current measured at 200 ms. In conclusion, -subunits modulate Nav1.5 gating with important differences between co-expression of 1 and 3 alone and 1/3 together.  相似文献   

10.
Summary A small population of T cells does not express the conventional T cell receptor characterized by the and polypeptide chains (TCR) but instead, two polypeptides termed and (TCR). This alternative receptor is able to recognize antigen. It appears early in T cell ontogeny, but its role in the thymus prior to the availability of TCR remains unclear. In selected sites such as skin or gut TCR predominates in mice which might suggest a role of T cells in the first line of defense against infection, T cells secrete lymphokines and display cytotoxic activity. However, their activation requirements may differ from what is known for T cells since MHC-nonrestricted and also CD4 and CD8 negative T cells have been described. Preferential activation by mycobacterial antigens possibly indicates a special repertoire of the T cells. In various diseases slightly increased numbers of T cells were found, but these preliminary studies have not yet provided evidence for a major pathogenetic role of T cells.List of abbreviations C constant region (immunoglobulin or TCR gene segment) - CD4 cluster of differentiation 4 (mainly on helper cells) - CD8 cluster of differentiation 8 (mainly on cytotoxic cells) - D diversity region (immunoglobulin or TCR gene segment) - DNA desoxyribonucleic acid - IL2 interleukin 2 - J joining region (immunoglobulin or TCR gene segment) - kD kiloDalton - MHC major histocompatibility complex - NK natural killer (cells) - RA rheumatoid arthritis - TCR T cell receptor - V variable region (immunoglobulin or TCR gene segment)  相似文献   

11.
The hypothesis that acute ethanol uptake plus trauma can synergize to increase immunosuppression was tested. We found that, unlike non-alcohol-exposed patients, patients with acute alcohol use prior to trauma have a transient decrease in monocyte tumor necrosis factor (TNF) production during the very early postinjury (0–3 days) period. However, TNF production by these alcoholexposed patients' monocytes (MØ) became hyperelevated late postinjury (>9 days). Consequently, these massively elevated MØ TNF levels can contribute to posttrauma immunosuppression after acute alcohol use. We also demonstrate that normal monocyte activation with the superantigen,Staphylococcus enterotoxin B (SEB), results in a preferential induction of cellassociated MØ TNF production, described as characteristic of immunosuppressed trauma patients. Acutein vitro ethanol treatment down-regulated the elevated TNF production by trauma patients' MØ after either SEB, muramyl-dipeptide (MDP), interferon- plus MDP, or lipopolysaccharide (LPS) stimulation. Both SEB- and LPS-induced TNF mRNA induction was inhibited by acute alcohol treatment in normal MØ, indicating that ethanol can regulate cytokine gene expression. An additional immunosuppressive effect of acute ethanol's stimulation was suggested by its induction of elevated transforming growth factor production in trauma patients' activated MØ.  相似文献   

12.
TGF- has been implicated in scarring and tissue fibrosis. Most cells secrete TGF- as a high molecular weight, latent complex that must be processed to a lower molecular weight, biologically active form. A number of molecules are involved in this activation step including the mannose 6-phosphate/insulin-like growth factor- II receptor, tissue transglutaminase, thrombospondin, plasmin, and others. Here we describe a rapid macrophage-based system for TGF- 1 activation, which could be used for screening potential anti- fibrotic agents. The system employs transformed mouse peritoneal macrophages treated with lipopolysaccharide as a cell line capable of activating latent TGF-. The activation mechanism in our system involves mannose 6-phosphate/insulin-like growth factor-II receptor andtransglutaminase. The activation of latent TGF- in this system can be prevented by the addition of mannose-6-phosphate but not mannose-1-phosphate. In addition, transglutaminase inhibitors, antibodies to thrombospondin, insulin-like growth factor- II in the presence of its binding protein IGFBP-2, but not IGFBP-1, suppressed the activation of TGF-. Anti-inflammatory molecules, such as hydrocortisone, when added to LPS-treated macrophages, inhibited TGF- activation by a mechanism, that may involve downregulation of transglutaminase expression. In summary, this new, rapid and reproducible system allows testing molecules for their ability to inhibit TGF- activation, thus providing a screening method for potential anti-scarring molecules.  相似文献   

13.
A paradigm exists that multiple sclerosis is causally related to dysregulation of TH1 inflammatory cytokines and TH2 antiinflammatory cytokines. The cytokine source(s) that initiate the imbalances are unknown. In this study, , CD4, and CD8 T cell receptor-positive (TCR+) cells were isolated from the blood of 26 definitive relapsing-remitting multiple sclerosis patients prior to interferon -1a (IFN1a) therapy and following 8–10 weeks of this therapy. The bioactivities of interferon (IFN), interleukin 10 (IL10), and interleukin 12 (IL12) were determined. The concentrations of IFN, IL10, and IL12 from each cell type did not change significantly with IFN1a treatment. The IL10 secreted by TCR+ cells strongly correlated with the IL12 secreted by the same TCR+ cells, supporting the paradigm. Furthermore, IFN1a therapy decreased the TCR+ cell secretion of TH1 cytokines after 8–10 weeks of therapy.  相似文献   

14.
-CCM is a -carboline known to have properties opposite to those of benzodiazepines. Our approach was to analyze, in mice, the genetic mechanisms involved in -CCM-induced myoclonic seizures using recombinant congenic strains and F1 hybrids issued from these strains. Our aim was to define the extent of the multigenic character of -CCM-induced myoclonic seizures, while also evaluating the distribution of the strength of the genes implicated in this trait. The results show that the control of reactivity to -CCM is multigenic with notable epistatic involvement.  相似文献   

15.
Summary It has been shown, by using the immunogold technique, that C-peptide and insulin are co-localized in the mature granules of human pancreatic cells and insulinomas with typical granules. The mean gold bead densities of both C-peptide and insulin were at least twice as high in the normal pancreas when compared with the insulinomas. The mean granule diameter of the insulinoma cells (D=0.30 ±0.12 m) was smaller than that of human pancreatic cells (D=0.45 ±0.15 m). The morphometric data indicate that each of the antigens (C-peptide and insulin) is distributed similarly in the halos and the dense cores of the granules. Thus, no topological segregation of these two antigens occurs within the granules of either normal human pancreas or insulinomas.  相似文献   

16.
Sera and questionnaire data from a population-based random sample of healthy adults was used to evaluate factors influencing neopterin and 2-microglobulin (2m) values. Both neopterin and 2m levels increased with age and were higher among white than blacks (mean values for whites and blacks: neopterin, 5.06 vs 4.49 nmol/L; 2m, 1.36 vs 1.28 mg/L). Gender differences were noted for 2m but not neopterin values (2m males vs females: 1.37 vs 1.29 mg/L). Neopterin values were lower among current smokers than among nonsmokers (4.32 vs 5.16 nmol/L) and were higher among users of antihistamines (5.46 among users vs 4.65 nmol/L among nonusers). Neopterin and 2m were correlated in this healthy adult population (adjustedr=0.53,P=0.001), yet no other interrelationships with numerous biologic markers except between 2m and serum-soluble interleukin-2 receptor levels (adjustedr=.41,P=0.05) were observed. These findings provide important baseline information to consider before planning or evaluating studies utilizing neopterin or 2m levels.  相似文献   

17.
TGF- plays a central role in the initiation and progression of pulmonary fibrosis. Glucocorticoids are frequently used to treat fibrotic diseases, but beneficial effects are often modest. Both TGF- and glucocorticoids have been reported to increase fibroblast contraction of native collagen gels, a model of fibrotic tissue remodeling. Therefore, we sought to determine how glucocorticoids interact with TGF- in this system. In this study, human fetal lung fibroblasts (HFL-1) were pretreated with or without TGF- for 72 h before they were cast into type I collagen gels. Various concentrations of glucocorticoids (budesonide or hydrocortisone) were added at the time of casting. Gel size was then monitored at different times after gel release. The surrounding media were collected for the assay of prostaglandin E2 (PGE2) and the cell lysates were analyzed for cyclooxygenase (COX) expression by immunoblot. Glucocorticoids alone significantly enhanced fibroblast-mediated contraction of collagen gels (P < 0.01) and dose-dependently inhibited PGE2 release by HFL-1 fibroblasts. TGF- significantly augmented gel contraction but also induced a 30% increase in PGE2 release and increased the expression of COX-1. Glucocorticoids inhibited TGF-1 induced-PGE2 release, and enhanced TGF- augmented gel contraction without significantly affecting TGF- augmented COX-1 expression. Indomethacin, a COX inhibitor, increased TGF- augmented gel contraction but had no further effect when added together with glucocorticoids. Thus, glucocorticoids can synergize with TGF- in augmenting fibroblast mediated collagen gel contraction through the inhibition of PGE2 production. Such interactions between glucocorticoids and TGF- may account, in part, for the lack of response of fibrotic diseases to glucocorticoids.  相似文献   

18.
According to the amyloid cascade hypothesis, sporadic Alzheimers disease (AD) is caused by the production and aggregation of -amyloid (A), and the production of A has recently been linked to the metabolism of cholesterol. We have previously published clinical studies where the effect of statin treatment on A production has been investigated. No effect on A was found, which is in disagreement with cell and animal studies. In the present study we investigated the effect of statin treatment on a disease-specific pattern consisting of a C-terminally-truncated quintet of A peptides. Nineteen patients with AD were treated with simvastatin for 12 months and the quintet of A peptides were analysed in cerebrospinal fluid before and after treatment. Also included was a group of 15 untreated patients with AD. We found that the A peptide pattern at baseline was in agreement with earlier findings; however, we did not find any change in the A peptide pattern after statin treatment. We suggest that clinical studies with extended treatment periods are performed where higher dosages of statins are used. We also believe that the pleiotropic effects of statins should be investigated further in order to elucidate the connection between Alzheimers disease and statin treatment.  相似文献   

19.
Summary The distribution of restriction fragment length polymorphism (RFLP) at theBamH1 site of the -globin gene was investigated in the Chinese, Indian, and Malay race in Singapore. The sample comprised of 183 normal individuals and 35 -thalassemia carriers in which 13 were couples with at least one -major child. The results from this study indicate thatBamH1 polymorphism will be informative in 22% of pregnancies at risk for -thalassemia major in Chinese, 19% in Malays and 7% in Indians. In prenatal diagnosis usingBamH1 polymorphism for one -major affected family, the fetus was diagnosed to be normal or -carrier. The validity ofBamH1 polymorphism in the exclusion of -thalassemia major was subsequently confirmed at birth by globin chain biosynthesis.  相似文献   

20.
This paper reviews the evidence indicating possible roles for tumour necrosis factor-alpha (TNF) in development. It is proposed that TNF may have essentially three major roles during embryonic development, which may be analogous to its roles in the immune system and during inflammation: a role in programmed cell death; a role as a cellular growth and differentiation factor; and also a role in the remodelling of extracellular matrix, and the regulation of cell adhesion molecules and integrins. The concept of the existence of a cytokine array during embryogenesis, analogous to that occurring in inflammation, is discussed, as well as potential roles for TNF in the induction of ubiquitin; protective mechanisms embryonic cells may employ against TNF-mediated cytotoxicity; and a consideration of the role TNF may play in a free radical theory of development.  相似文献   

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