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31.
H. R. Maurer H. T. Hassan C. Tsiriyotis D. A. Spandidos 《Journal of cancer research and clinical oncology》1992,118(5):329-333
Summary The effects of recombinant human interferons , and (IFN) on the antiproliferative activity of cytarabine in K562 human myeloid leukaemia clonogenic cells were studied in an agar capillary microassay. The addition of IFN- did not affect the antiproliferative activity of cytarabine in K562 cultures treated with low concentrations of cytarabine (10–50 nM), whereas in those treated with high concentrations (100–150 nM) IFN increased the IC50 of cytarabine on day 5 from 102 nM to 214 nM, i.e., cytarabine combined with IFN was about two-fold less potent than cytarabine alone. Similarly, low concentrations of IFN and IFN did not affect the antiproliferative activity of cytarabine on K562 colonies, but high concentrations of these two interferons: 4×103 U/ml and 104 U/ml respectively, increased the IC50 of cytarabine on day 5 to 304 nM and to 316 nM respectively, i.e. cytarabine combined with IFN or IFN was about threefold less potent than cytarabine alone. The evaluation of the present negative interactions of interferons with cytarabine is warranted in fresh cells from myeloid leukaemia patients in primary culture.Abbreviation IFN
interferon 相似文献
32.
David de Wied Jan M. van Ree 《European archives of psychiatry and clinical neuroscience》1989,238(5-6):323-331
Summary Animal studies have demonstrated that neuropeptides modulate nervous system functions. It has been postulated that disturbances in neuropeptide systems may be aetiological factors in psychiatric and neurological disorders. Neuropeptides related to ACTH/MSH, including ORG 2766, increase motivation and attention and facilitate recovery processes after nerve damage. These peptides may be effective during the early stage of dementia. Vasopressin and related peptides improve memory processes in animals and humans. In addition, these peptides influence social behaviour, mood and addictive behaviour. The non-opioid -type endorphins have neurolepticlike activities in animals and antipsychotic effects in a category of schizophrenic patients. Peptides related to CCK have also been found to be effective in these patients. Some neuropeptides, e.g. TRH and PLG, have been reported to exert antidepressant effects. Further research may eventually produce neuropeptides with therapeutic action in psychiatric and neurological diseases.Parts of this article were presented on the occasion of the inauguration ceremony of the Department of Psychiatry of the University of Mainz on April 2 and 3, 1987 相似文献
33.
van Hoogdalem Ewoud J. Heijligers-Feijen Cornelia D. de Boer Albertus G. Verhoef J. Coos Breimer Douwe D. 《Pharmaceutical research》1989,6(1):91-95
The stability of the neuroleptic peptide des-enkephalin--endorphin (DEE; Org 5878) in the rectal lumen and the rectal bioavailability of DEE were investigated in conscious rats. Furthermore, the influence of peptidase inhibition, peptidase saturation, and absorption enhancement on DEE bio-availability were evaluated. Na2EDTA (0.25%, w/v) prolonged the degradation half-life of DEE in the ligated colon from 33 ± 7 to 93 ± 45 min. Without adjuvant, tritium-labeled DEE was absorbed from the rat rectum to a very low extent (0–4%). After administration of an excess of unlabeled DEE or with Na2EDTA, comparable results were obtained. The medium-chain glyceride preparation MGK markedly enhanced the rectal DEE bioavailability, up to 8–20%, which was further increased to 10–44% by coadministration of Na2EDTA. No substantial influence of varying the rectal delivery rate was observed. The results suggest that absorption enhancement and enzyme inhibition both are essential for effective increase of rectal peptide bioavailability. 相似文献
34.
Preservation and redirection of HPV16E7-specific T cell receptors for immunotherapy of cervical cancer 总被引:6,自引:0,他引:6
Scholten KB Schreurs MW Ruizendaal JJ Kueter EW Kramer D Veenbergen S Meijer CJ Hooijberg E 《Clinical immunology (Orlando, Fla.)》2005,114(2):119-129
Human papilloma virus (HPV) type 16 infections of the genital tract are associated with the development of cervical cancer (CxCa) in women. HPV16-derived oncoproteins E6 and E7 are expressed constitutively in these lesions and might therefore be attractive candidates for T-cell-mediated adoptive immunotherapy. However, the low precursor frequency of HPV16E7-specific T cells in patients and healthy donors hampers routine isolation of these cells for adoptive transfer. To overcome this problem, we have isolated T cell receptor (TCR) genes from four different HPV16E7-specific healthy donor and patient-derived human cytotoxic T lymphocyte (CTL) clones. We examined whether genetic engineering of peripheral blood-derived CD8+ T cells in order to express HPV16E711-20-specific TCRs is feasible for adoptive transfer purposes. Reporter cells (Jurkat/MA) carrying a transgenic TCR were shown to bind relevant but not irrelevant tetramers. Moreover, these TCR-transgenic Jurkat/MA cells showed reactivity towards relevant target cells, indicating proper functional activity of the TCRs isolated from already available T cell clones. We next introduced an HPV16E711-20-specific TCR into blood-derived, CD8+ recipient T cells. Transgenic CTL clones stained positive for tetramers presenting the relevant HPV16E711-20 epitope and biological activity of the TCR in transduced CTL was confirmed by lytic activity and by interferon (IFN)-gamma secretion upon antigen-specific stimulation. Importantly, we show recognition of the endogenously processed and HLA-A2 presented HPV16E711-20 CTL epitope by A9-TCR-transgenic T cells. Collectively, our data indicate that HPV16E7 TCR gene transfer is feasible as an alternative strategy to generate human HPV16E7-specific T cells for the treatment of patients suffering from cervical cancer and other HPV16-induced malignancies. 相似文献
35.
Osteopontin affects the persistence of beta-glucan-induced hepatic granuloma formation and tissue injury through two distinct mechanisms 总被引:4,自引:0,他引:4
Morimoto J Inobe M Kimura C Kon S Diao H Aoki M Miyazaki T Denhardt DT Rittling S Uede T 《International immunology》2004,16(3):477-488
Osteopontin (OPN) plays a pivotal role in various immune responses and inflammatory diseases. OPN is expressed in various granulomatous diseases; however, the cellular and molecular role of OPN in these diseases is not well known. We analyzed the role of OPN in a beta-glucan-induced hepatic granuloma model. First, we found that neither OPN deficiency nor overexpression of OPN affected the number and the size of hepatic granulomas at day 7, indicating that OPN is not involved in the formation of hepatic granulomas at the early stages. Importantly, OPN did not influence the liver tissue damage as defined by alanine aminotransferase and aspartate aminotransferase levels at early stages. Second, OPN deficiency resulted in the reduction of IL-12 and IFN-gamma production at early stages. Third, at late stages, OPN deficiency resulted in a decrease in the number and size of hepatic granulomas, and a reduction of liver tissue injury. This was due to the reduction of the cellular recruitment including macrophages, CD4 T cells and dendritic cells into the liver, and the reduction of tumor necrosis factor (TNF)-alpha production in the liver. In contrast, overexpression of OPN resulted in the persistence of granuloma formation. These data suggest that OPN affects the persistence of hepatic granuloma formation. Our results indicate that OPN up-regulates the production of IL-12 and IFN-gamma within the granulomas at early stages, and OPN has an additional role in the regulation of cellular recruitment and TNF-alpha production at late stages that determine the severity of liver tissue injury. 相似文献
36.
37.
目的:建立新的土拨鼠α干扰素(IFN-α)基因分型方法,分析急性和慢性土拨鼠肝炎病毒(Woodchuck hepati-tis virus,WHV)感染的土拨鼠肝细胞中不同型别的IFN-α基因表达谱及其意义。方法:利用已知序列和基因型的土拨鼠IFN-α基因克隆质粒,建立基于土拨鼠IFN-α基因序列的限制性片段长度多态性的土拨鼠IFN-α基因分型方法。PolyIC体外刺激正常土拨鼠外周血单个核细胞(PBMC),调查正常土拨鼠PBMC受PolyIC刺激后IFN-α基因的表达谱。提取急性和慢性土拨鼠肝炎病毒感染的土拨鼠肝组织mRNA,RT-PCR扩增土拨鼠IFN-α基因,分子克隆后调查急性和慢性感染的土拨鼠肝细胞中IFN-α基因表达谱。结果:建立了土拨鼠IFN-α基因限制性片段长度多态性分型方法。急性和慢性感染的土拨鼠肝细胞中IFN-α基因的表达谱明显不同于正常动物的表达谱,假基因表达所占比例大。结论:新建立的土拨鼠IFN-α基因分型方法可用于分析土拨鼠不同组织中IFN-α的基因表达谱。 相似文献
38.
D.S. Linthicum 《Immunobiology》1982,162(3):211-220
The development of acute experimental autoimmune encephalomyelitis (EAE) in mice is potentiated by the use of Bordetella pertussis vaccine as an adjuvant. Histamine sensitizing factor (HSF) extracted from B. pertussis is the active adjuvant agent and causes a mild increase in cerebrovascular permeability. During the development of EAE, there is an additional increase in vascular permeability of the brain and spinal cord. The adjuvant action of B. pertussis HSF does not appear to mimic a generalized beta-adrenergic blockade, since the course of EAE is not potentiated by adrenalectomy. The cerebrovascular permeability changes observed in EAE are probably mediated by vasoactive amines, since the expression of EAE can be blocked by vasoactive amine antagonists. 相似文献
39.
Amy C. Fuchs Eric V. Granowitz Leland Shapiro Edouard Vannier Gerhard Lonnemann Jonathan B. Angel Jeffrey S. Kennedy Arthur R. Rabson Elaine Radwanski Melton B. Affrime David L. Cutler Paul C. Grint Charles A. Dinarello 《Journal of clinical immunology》1996,16(5):291-303
We conducted a double-blind, placebo-controlled study to investigate the safety, pharmacokinetics, and immunological properties of interleukin-10 (IL-10) administration in healthy humans. Volunteers received a single intravenous bolus injection of recombinant human IL-10 (1, 10, or 25g/kg) or placebo. Cytokine production in whole blood and peripheral blood mononuclear cells (PBMC) was assessed before and 3, 6, 24, and 48 hr after the injection. Peak serum concentrations of IL-10 (15±1.1, 208±20.1, and 505±22.3 ng/ml) occurred after 2–5 min for 1, 10, and 25g/kg IL-10, respectively. The terminal-phase half-life was 3.18 hr. A transient leukocytosis (24–63% above baseline) was observed 6 hr after injection, which coincided with a dose-dependent decrease (12–24%) in neutrophil superoxide generation. There was a marked inhibition (60–95%) of endotoxin-induced IL-6 production from whole blood in each group receiving IL-10. Production of IL-8 in endotoxin-stimulated blood was reduced in the 10g/kg group. In PBMC stimulated with phytohemagglutinin and phorbol ester, there was a decrease (72–87%) in interferon- (IFN) production 6 hr after IL-10 with a return to pre-IL-10 levels after 24 hr. This reduction was only partially associated with a decrease in the number of CD2-bearing cells. We conclude that IL-10 administration into humans is without significant side effects, and a single injection reducesex vivo production of IL-6, IL-8, and IFN. 相似文献
40.
Yu Wen-Gong; Yamamoto Noriniko; Takenaka Hiroshi; Mu Jie; Tai Xu-Guang; Zou Jian-Ping; Ogowa Makoto; Tsutsui Tateki; Wijesuriya Rishani; Yoshida Ryotaro; Herrmann Steven; Fujiwara Hiromi; Hamaoka Toshiyuki 《International immunology》1996,8(6):855-865
The present studnt Investigates the molecular by which IFN-produced as a result of in vitroIL-12 addministration exertsits anty-tumor,rIL-12 was administered three or five times intomice bearing CDA1M fibrosarcoma, OV-HM ovarian carcinoma orMCH-1-A1 fibosarcoma. This regimen induced complete regressionof CSA1M and OV-HM tumors but only transient growth inhibitionof MCH-1-A1 tumors. The anty-tumor effects of Il-12 were associatatedwith enhanced induction of IFN-becouse these effects were abrogatedby pretreatment of hosts with anti-IFN- antibody.Exposure inin vitro of the three types of tumor cells to rIFN- resultedin moderate to potent inhibition of tumor cell growth.IFNstimulatedthe expression of mRNAs for an inducible type of NO synthasa(INOS)in CSA1M cells and indoleamine 2,3-dioxygenasa (IDO),an enzyme capable of degrading tryptophan, in OV-HM cells ,but induced only marginal levels of these mRNAs in MCH-I-ALcells. In association withiNOS gene expression, INF--stimulatedCSA1M cells produced a large amount of NO which functioned toinhibit their own growth in vitro. Although OV-HM and MCH-1-A1cells did not produce NO, they also exhibited NO susceptibility.Whereasthe tumor masses from IL-12-treated CSA1M-bearing mice inducedhigher levels of INOS (for CSA1M) or IDO and iNOS (for OV-HM)mRNAs,the MCH-1-A1 tumor mass expressed lower levels of iNOS mRNAalone.Moreover, massive infiltration of CD4+and CD8+ T cellsand Mac-1+ cells was seen only in the CSA1M and OV-HM tumors.Thus, these results indicate that IFN- produced after IL-12treatment induces the expression of various genes with potentialto modulate tumor cells and growth by acting directly on tumorecells or stimulating tumor-infiltrating lymphold cells and thatthe effectiveness of IL12 therapy is assoiated with the operation if these mechanisms. 相似文献