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Summary The antitumor effects of chemotherapy, recombinant human interleukin-2 (IL-2), recombinant human interferon A/D (IFN), allogeneic human lymphokine-activated killer (LAK) cells, and antitumor monoclonal antibody (mAb), administered alone and in various combinations, were tested in athymic nude mice carrying human tumor xenografts. Treatment began 6–18 days after i.v. or i.p. inoculation of colorectal carcinoma or melanoma cell lines, when macroscopic growths were evident. Chemotherapy consisted of two or three courses of 5-fluorouracil (5-FU) or dacarbazine. IL-2 and/or IFN were administered three to five times weekly for 1–3 weeks, usually starting 2–5 days after chemotherapy. Human LAK cells were infused once or twice weekly for 2 or 3 weeks concurrently with IL-2. In some experiments, murine anticolorectal carcinoma mAb (SF25) was administered. In both tumor systems, chemotherapy alone or immunotherapy alone (IL-2, IL-2 + LAK cells, IFN, IL-2 + IFN ± LAK cells) had little or no therapeutic effects. Additive effects were obtained by combining chemotherapy with IL-2 and LAK cells or with IL-2 and IFN. In the majority of the experiments, the most effective combination was chemotherapy + IL-2 + IFN + LAK cells. Treatment with mAb was beneficial in the colorectal carcinoma system when combined with 5-FU + IL-2 or 5-FU + IL-2 + IFN. Homing experiments with radiolabeled human and mouse LAK cells injected i.v. showed increased early accumulation in the liver and lungs, whereas freshly explanted mouse splenocytes localized mostly in the spleen and liver. The tissue distribution pattern of human LAK cells was similar in normal and tumor-bearing mice (with lung metastases). These findings suggest that combination of chemotherapy with cytokines and LAK cells can be partially effective for advanced solid human tumors even in the absence of the host's T-cell immune response. Preliminary experiments showed that tumor-specific, anti-melanoma T-cell clones were effective in local (s.c.) tumor growth inhibition (Winn assay) following coinjection with the autologous tumor cells.  相似文献   
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Summary T cell clones derived from a chronic myelogenous leukaemia (CML) patient during interferon (IFN, Wellferon) biotherapy preferentially lysed autologous rather than allogeneic CML target cells in an apparently MHC-unrestricted fashion, but also lysed bone marrow cells from certain normal donors regardless of whether or not they shared HLA antigens with the patient. Although T cell clones inhibited both CML and normal bone marrow in the colony-forming assay, they blocked proliferation of CML cells more efficiently than bone marrow cells. This inhibitory effect was mediated at least in part by the tumour necrosis factor (TNF) and IFN secreted by the clones. Antisera to these cytokines partially prevented inhibition. Involvement of additional factors is also suggested in blocking CML cell proliferation because this was not 100% inhibited even by a combination of TNF and IFN. In addition, most clones failed strongly to block the proliferation of normal bone marrow cells, which were susceptible to inhibition by these cytokines.This work was supported in part by the Deutsche Forschungsgemeinschaft (SFB 120)  相似文献   
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Circulating interleukin-6 (IL-6) concentrations correlate with disease activity in severe inflammatory conditions, in sepsis and in some hematological malignancies. On the other hand, IL-6 is a potent stimulator of osteoclastogenesis and has been implicated as a contributory factor in the genesis of osteopenic conditions. We measured circulating IL-6 levels by a sensitive (detection limit of 10 U/ml) and specific bioassay in 103 patients with advanced cancer, including 41 with tumor-induced hypercalcemia before any specific hypocalcemic therapy. We related IL-6 concentrations to clinical features and to biochemical parameters of bone metabolism, including blood Ca, Ca2+, Pi, intact parathyroid hormone, parathyroid hormone-related protein, osteocalcin, 1,25-(OH)2-vitamin D and, as markers of bone resorption, the fasting urinary excretion of calcium (Ca/creatinine) and hydroxyproline. IL-6 levels were increased, i.e. detectable, in 23% of the patients, 8/41 (20%) hypercalcemic and 16/62 (26%) normocalcemic patients (NS); the distribution of the values was similar in the two groups. The presence of increased IL-6 concentrations was not related to any clinical characteristic, notably not to the survival nor to the existence of bone metastases, whether in hypercalcemic or normocalcemic patients; e.g., only 3/12 (25%) hypercalcemic subjects without bone metastases had elevated IL-6 levels. We found no significant correlations between IL-6 concentrations and any of the biochemical parameters studied. Hypercalcemic subjects with increased IL-6 had higher urinary Ca/creatinine levels than patients with normal IL-6 levels (P<0.005) but this was not the case in normocalcemic subjects. Mean concentrations of inflammatory or other bone metabolism markers were not significantly different between patients with normal or with elevated IL-6 levels. In summary, circulating IL-6 levels were increased in 23% of 103 patients with advanced cancer, but the frequency of increased IL-6 concentrations was not related to the presence of hypercalcemia or to any marker of calcium metabolism or bone turnover. The pathogenic importance of circulating IL-6 in patients with solid tumors remains to be demonstrated and our data indicate that increased circulating levels of IL-6, possibly reflecting the activation of the immune system, only contribute in a minor way to the osteolytic process in patients with tumor-induced hypercalcemia.  相似文献   
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Prediabetes is an increase-risk state for diabetes that is associated with an increase in blood glucose levels to more than normal, but not increased enough to be termed as type 2 diabetes mellitus (T2DM). A timely intervention and management of prediabetes can stop its further progression to the diabetic state. Many cytokines are involved in diseases including diabetes, however, their role in prediabetes is unknown. In this study, we attempted to analyze numerous proinflammatory cytokines in prediabetic patients. A total of 60 adult Saudi prediabetes patients and healthy control individuals were included in this study. To better understand the role of the proinflammatory cytokines in prediabetes patients and its potential link to the disease outcome, the variations in the levels of these cytokines were investigated using Multi-Analyte ELISA technique. The T helper cells (Th1 and Th2) immune response expression profiling of 84 genes was done using Real Time-quantitative PCR (RT-qPCR) technique. The present finding showed that serum Interleukin IL-2, IL-1β, and IL-1α levels of all prediabetes patients were increased when compared with healthy control cases (P < 0.05). Inductions of proinflammatory cytokines and upregulation of Th1 and Th2 immune genes might play a potential role during prediabetes status and may be linked to the disease outcome. Further studies are needed to investigate the underlying mechanism of these proinflammatory cytokines in diabetes development. A strong positive correlation was found between IL and 1α with glucose levels than with IL-1β and IL-2. In conclusion, cytokines, especially IL-1, may play a critical role in the development of diabetes.  相似文献   
6.
Measurement of cytokine antibodies. Test development   总被引:1,自引:0,他引:1  
Several assays have been used for detection of antibodies against cytokines. The choice of assay is greatly dependent on the intended goal, e.g. detection of naturally occurring antibodies or therapy induced antibodies. The different assays can be grouped in 2 categories. The interference or indirect assays are based on the detection of the test sample interference with the biological activity, with detection of the cytokine in EIA or with binding to cellular receptors. In direct assays cytokine antibodies are detected by binding to solid phase fixed cytokines, followed by incubation with a secondary enzyme-labelled anti-human Ig antibody or by binding to125I-labelled cytokines in RIA.  相似文献   
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Helicobacter pylori, T cells and cytokines: the "dangerous liaisons"   总被引:1,自引:0,他引:1  
Helicobacter pylori infection is the major cause of gastroduodenal pathologies, but only a minority of infected patients develop chronic and life threatening diseases, as peptic ulcer, gastric cancer, B-cell lymphoma, or autoimmune gastritis. The type of host immune response against H. pylori is crucial for the outcome of the infection. A predominant H. pylori-specific Th1 response, characterized by high IFN-gamma, TNF-alpha, and IL-12 production associates with peptic ulcer, whereas combined secretion of both Th1 and Th2 cytokines are present in uncomplicated gastritis. Gastric T cells from MALT lymphoma exhibit abnormal help for autologous B-cell proliferation and reduced perforin- and Fas-Fas ligand-mediated killing of B cells. In H. pylori-infected patients with autoimmune gastritis cytolytic T cells infiltrating the gastric mucosa cross-recognize different epitopes of H. pylori proteins and H+K+ ATPase autoantigen. These data suggest that peptic ulcer can be regarded as a Th1-driven immunopathological response to some H. pylori antigens, whereas deregulated and exhaustive H. pylori-induced T cell-dependent B-cell activation can support the onset of low-grade B-cell lymphoma. Alternatively, H. pylori infection may lead in some individuals to gastric autoimmunity via molecular mimicry.  相似文献   
10.
We have used cytokine protein array to analyze the secretion of cytokines from an osteoblastic clone derived from human umbilical cord blood mesenchymal stem cells (MSCs) cultured in an osteogenic differentiation medium. The analysis demonstrated the unexpected ability of osteoblast committed cells and their early progenitors to produce significant amounts of a range of soluble immune mediators without in vitro exposure to clinically relevant bacterial pathogens. The cells were expanded and their osteogenic potential analyzed over 45 days of culture was revealed by the expression of osteoblast-specific markers (alkaline phosphatase and Runx2), and by matrix mineralization. Over this culture period, the cells secreted particularly high levels of IL-8, MCP-1 and VEGF, but did not express IL-2, IL-7, IL-17, eotaxin, G-CSF and IFN-gamma. These findings should encourage the use of human umbilical cord blood as a potential stem cells source for bone regeneration.  相似文献   
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