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91.
Local production and localization of transforming growth factor-beta in tuberculous pleurisy. 总被引:5,自引:1,他引:5
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J Maeda N Ueki T Ohkawa N Iwahashi T Nakano T Hada K Higashino 《Clinical and experimental immunology》1993,92(1):32-38
Transforming growth factor-beta (TGF-beta) is one of the cytokines which play an immunosuppressive role in an inflammatory process. To investigate the local production of TGF-beta, we evaluated the levels of TGF-beta in tuberculous pleural effusions (TBPE) and non-tuberculous benign pleural effusions (non-TBPE) by the growth inhibition assay with Mv1Lu mink lung epithelial cells. The mean level of TGF-beta in TBPE (46.1 +/- 31.5 pM; mean +/- s.d.) was higher than in non-TBPE (21.7 +/- 12.3 pM) (P < 0.05). Although the level of interferon-gamma (IFN-gamma) in TBPE measured by ELISA was significantly higher than in non-TBPE, there was no significant difference in the levels of tumour necrosis factor-alpha (TNF-alpha) measured by ELISA between these two groups. Moreover, to elucidate localization of TGF-beta in tuberculous pleurisy, immunohistochemical studies of pleura, using the rabbit polyclonal antibody Ab39 against latent TGF-beta 1 binding protein (LTBP) were performed. Results revealed that LTBP was localized in immature fibrotic areas where infiltrations of T lymphocytes and macrophages were absent. Importantly, the major sources of LTBP in these areas were thought to be mesothelial cells and fibroblasts. LTBP was not found in granulomas and mature fibrotic areas. Our data suggest that TGF-beta in tuberculous pleurisy may play important roles for regression of granulomatous inflammation and pleural fibrosis for tissue repair. 相似文献
92.
Murata T Nakamura S Oka K Kawakami K Kato M Imai T Nakayama T Kuroda M Nakano H Watanabe M Shiraishi T 《Pathology international》2000,50(10):853-857
A case of primary gastric T-cell lymphoma, which was positive for granzyme B, is reported. The patient was a 47-year-old Japanese female who complained of a dull upper abdominal pain. Radiographic and endoscopic examinations revealed an ulcerative infiltrative lesion in her stomach. Following the confirmation of a high-grade malignant lymphoma, a distal gastrectomy with regional lymph nodal dissection was performed. The histology of the gastric lesion revealed a malignant lymphoma of the diffuse pleomorphic type without lymph nodal involvement. Immunohistochemistry revealed that the tumor cells were positive for LCA, CD3, TIA-1 and granzyme B, but were negative for CD4, CD8, CD56, CD30, L-26, EMA, TCR alpha/beta and TCR gamma/delta. Because the tumor cells showed T cell nature with cytotoxic activity proved by TIA-1 and granzyme B, and without evidence of further maturation of T cell, a malignant lymphoma originating from extrathymic-derived T cells was suggested. 相似文献
93.
Nakano Y Nagamatsu Y Ohshima Y 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(9):773-779
Mechanisms involved in the control of body size are largely unknown. In the nematode C. elegans, several small body size mutants were isolated, and the responsible genes were reported to encode putative components of a TGFbeta signalling pathway. Recently, mutants in the egl-4 gene encoding cGMP-dependent protein kinases were found to have a larger body size, and it was suggested that EGL-4 down-regulates the TGFbeta/DBL-1 pathway. We show that a permeable cGMP analogue 8-Br-cGMP significantly reduces body size of the wild-type but not that of an egl-4 mutant, indicating that cGMP controls body size through EGL-4. Laser ablation of germ-line cells revealed that a germ-line signal and EGL-4 function in the same pathway. Targeted expression of EGL-4 indicates that EGL-4 can function in hypodermis, neurones and intestine both cell-autonomously and cell-nonautonomously to control organ and body size. We propose a signal cascade for the control of body size that involves a germ-line signal, cGMP, G-kinase EGL-4 and DBL-1/TGFbeta pathway. It is interesting that two important pathways involving cGMP and TGFbeta, respectively, are related. Also, the results suggest a novel mechanism for the control of organ and body size in which hypodermis plays a key role 相似文献
94.
Inflammation Research - 相似文献
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98.
Study of the biological activities of toxic shock syndrome toxin-1: II. Induction of the proliferative response and the interleukin 2 production by T cells from human peripheral blood mononuclear cells stimulated with the toxin 总被引:7,自引:1,他引:7
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T. Uchiyama Y. Kamagata Xiao-Jie Yan Masako Kohno M. Yoshioka H. Fujikawa H. Igarashi M. Okubo F. Awano T. Saito-Taki M. Nakano 《Clinical and experimental immunology》1987,68(3):638-647
Toxic shock syndrome toxin-1 (TSST-1) is an exotoxin produced by Staphylococcus aureus isolated from patients with toxic shock syndrome. We investigated the proliferative response of human lymphocytes and their interleukin 2 (IL-2) production after stimulation with TSST-1 in vitro. Human cord blood mononuclear cells (HCBM) and human peripheral blood mononuclear cells (HPBM) could proliferate with TSST-1 stimulation. T cell-depleted HPBM showed only a marginal response to this toxin. A IL-2-like factor with a molecular weight of 15-18 kD was obtained from the supernatants of TSST-1-stimulated HPBM cultures. The factor was absorbed by CTLL-2 cells but not by T cell-depleted murine spleen cells, indicating that it is IL-2. HPBM are very sensitive to TSST-1: a low concentration of TSST-1 (0.01 ng/ml in 36 h stimulation) and a short period of stimulation (8 h at 10 ng/ml of the toxin) were fully effective for HPBM to produce substantial amounts of IL-2. Removal of T cells abrogated the TSST-1-induced IL-2 production by HPBM. Reconstituted cell cultures of nylon wool column-passed T cells and macrophages produced IL-2 by TSST-1 stimulation and, furthermore, the accessory activity of the macrophages could be partially replaced by a macrophage-derived factor containing interleukin 1. These findings indicate that T cells require macrophages or IL-1 for TSST-1-induced production of IL-2. The roles of lymphokines, including IL-2, in the development of this illness are discussed. 相似文献
99.
Influence of culture method on the proliferation and osteogenic differentiation of human adipo-stromal cells in nonwoven fabrics 总被引:1,自引:0,他引:1
The initial attachment, proliferation, and osteogenic differentiation of stromal cells from human fat tissue were investigated in three-dimensional nonwoven fabrics prepared from polyethylene terephthalate (PET) fiber with different diameters. The largest number of cells initially attached was observed in the nonwoven fabrics prepared from PET fiber with a diameter of 22.0 microm, irrespective of fabric porosity. The number of cells attached was larger and the cells were distributed more homogeneously in the fabrics by the agitated seeding method than by the static seeding method. The culture method depended on the time profile of cell proliferation. Cell proliferation improved in the following order: stirred (spinner flask) culture method > agitated culture method > static culture method. In addition, cells proliferated homogeneously in fabrics by the stirred culture method. When evaluated as a measurement of cell osteogenic differentiation, the activity of alkaline phosphatase (ALP) was not influenced by the diameter of fabrics. The static culture method tended to enable cells to enhance ALP activity, in contrast with the stirred and agitated culture methods. It is concluded that fabric fiber diameter and culture method greatly affected the proliferation and differentiation of cells in nonwoven fabrics. 相似文献
100.
Characterization of a Helicobacter pylori neutrophil-activating protein. 总被引:25,自引:0,他引:25
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D J Evans Jr D G Evans T Takemura H Nakano H C Lampert D Y Graham D N Granger P R Kvietys 《Infection and immunity》1995,63(6):2213-2220
Helicobacter pylori-associated gastritis is mainly an inflammatory cell response. In earlier work we showed that activation of human neutrophils by a cell-free water extract of H. pylori is characterized by increased expression of neutrophil CD11b/CD18 and increased adhesiveness to endothelial cells. The work reported here indicates that the neutrophil-activating factor is a 150,000-molecular-weight protein (150K protein). Neutrophil proadhesive activity copurified with this protein, which is a polymer of identical 15K subunits. Specific antibody, prepared against the purified 15K subunit, neutralized the proadhesive activity of the pure protein and of water extracts obtained from different strains of H. pylori. The gene (napA) for this protein (termed HP-NAP, for H. pylori neutrophil-activating protein) was detected, by PCR amplification, in all of the H. pylori isolates tested; however, there was considerable strain variation in the level of expression of HP-NAP activity in vitro. HP-NAP could play an important role in the gastric inflammatory response to H. pylori infection. 相似文献