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101.
白细胞介素及肿瘤坏死因子基因超家族在先兆子痫胎盘中的表达 总被引:1,自引:0,他引:1
为探讨白细胞介素和肿瘤坏死因子 (受体 )超家族基因表达与先兆子痫病理发生的关系 ,以包含 2 4 3种人类细胞因子相关基因cDNA片段的基因芯片 ,检测严格配对的先兆子痫和正常胎盘组织中基因表达谱的差异。结果显示受检的白细胞介素和 (或 )白细胞介素受体基因共 2 2种 ,绝大多数基因在先兆子痫胎盘中的表达增强 ,而IL 2受体 (IL 2Rα )基因 (Gen Bank :X0 10 5 7)在先兆子痫胎盘中的表达低于正常胎盘。肿瘤坏死因子 (GenBank :X0 2 910 )及其配体 (GenBank :U0 3398、U375 18、AF0 5 3712、AF0 5 5 872 )、受体 (GenBank :X6 0 5 92、X6 3717、M835 5 4、AF0 16 2 6 6、AF0 16 2 6 7、U812 32 )等 10余种肿瘤坏死因子 (受体 )超家族基因在先兆子痫胎盘中的表达也较高。说明 ,白细胞介素及肿瘤坏死因子 (受体 )基因超家族的高表达可能与先兆子痫的病理发生关系密切 相似文献
102.
103.
M Fukuoka K Yasuda H Fujiwara H Kanzaki T Mori 《Human reproduction (Oxford, England)》1992,7(10):1361-1364
We have reported that the cytokines, interleukin-1 (IL-1), tumour necrosis factor alpha (TNF alpha), and interferon (IFN) alpha, beta, and gamma modulate the steroidogenic function of human luteinized granulosa cells in culture. In the present study we examined the interactions between these cytokines in modulating progesterone and oestradiol production by these cells. Neither IL-1 nor TNF alpha had significant effects on human chorionic gonadotrophin (HCG)-stimulated progesterone production, whereas IFN gamma (1-10 ng/ml) significantly reduced HCG-stimulated progesterone production by 26-37%. Concomitant treatment with IL-1 (1 ng/ml) did not further enhance the inhibitory effect of IFN gamma on HCG-stimulated progesterone production. In contrast, the combination of TNF alpha (1 ng/ml) and IFN gamma (10 ng/ml) acted synergistically to markedly inhibit HCG-stimulated progesterone production by 81%. In addition, IL-1 and TNF alpha, neither of which was effective alone, acted synergistically to reduce significantly HCG-stimulated progesterone production by 30%. The combination of TNF alpha and IFN gamma also markedly inhibited follicle stimulating hormone (FSH)-stimulated oestradiol production by 97%, a significantly greater inhibition than that obtained with either cytokine alone. These results suggest that the cytokines may interact to modulate the steroidogenic function of luteal cells in the developing corpus luteum. 相似文献
104.
David Baker Debra Butler Bernard J. Scallon Janet K. O'Neill John L. Turk Marc Feldmann 《European journal of immunology》1994,24(9):2040-2048
Tumor necrosis factor (TNF) activity was inhibited during the development of actively-induced, chronic relapsing experimental allergic encephalomyelitis (CREAE) in Biozzi AB/H mice, using a mouse TNF-specific (TN3.19.12) antibody and bivalent human p55 and p75 TNF receptor-immunoglobulin (TNFR-Ig) fusion proteins. The development of disease could be inhibited when repeated doses of antibody were administered prior to the anticipated onset. It has now also been shown that a therapeutic effect is evident even when antibody is administered after the onset of clinical signs, further indicating an important role for TNF in pathogenic effector mechanisms in CREAE. Although biologically-active TNF was not detected in the circulation, TNF-α was detected in lesions within the central nervous system (CNS). This suggested that the CNS may be the main site for TNF-specific immunomodulation and was supported by the observation that intracranial injection was significantly more potent than that administered systemically, for both antibody and TNFR-Ig fusion proteins. The fusion proteins were as effective as antibody at doses 10—100-fold lower than that used for antibody, reflecting their higher neutralizing capacity in vitro. Although treatment was not curative and relapse inevitably occurred in this model if treatment was not sustained, the data indicate that anti-TNF immunotherapy, especially within the CNS, can inhibit CREAE and may, therefore, be useful in the control of human neuroimmunological diseases. 相似文献
105.
N. Freudenberg P. Rahner C. Darda U. N. Riede M. Schubert K. Frenzer-Welle A. Kiss G. Veres T. Nees R. Lamers C. Kortsik 《Virchows Archiv : an international journal of pathology》1996,428(3):187-194
We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia. 相似文献
106.
Natural killer (NK) cells play an important role in host defense mechanisms against infection and neoplasia. Interferon- (IFN-) has been shown to activate NK cells and to augment their cytotoxic activity, albeit its role in the maturation pathway of NK cells has not been elucidated. The present study examined whether IFN- activates the immature NK subset (Free cells) to become cytotoxic and also ascertained whether IFN- uses the same pathway of activation as that mediated by interleukin-2 (IL-2). Incubation of sorted Free cells overnight with IFN- resulted in augmentation of their cytotoxic function against NK sensitive target cells. The enhanced cytotoxic activity was not accompanied by a new recruitment of NK-target binder cells but by an increase in the frequency of killer cells in the conjugate fraction. Activation of the Free subset by IFN- resulted in upregulation of CD69, CD11b, and CD2 surface expression and stimulated secretion of IFN-. Unlike IL-2, IFN- did not stimulate the Free cells to proliferate or secrete TNF- and activation of cytotoxicity and modulation of surface antigens by IFN- were independent of TNF-. The failure of IFN- to stimulate secretion and proliferation by Free cells appeared to be mediated by negative signals. This was corroborated in experiments demonstrating that when Free cells were cultured with both IFN- and IL-2, a significant inhibition was observed for both the IL-2 dependent secretion of TNF- and proliferation. These results demonstrate that IFN- serves as both an activator and a regulator of NK function. Further, activation of the immature Free NK cells by IL-2 and IFN- proceeds by TNF--dependent and independent pathways, respectively. The findings also support our contention that the mechanism of activation of the cytotoxic machinery of NK cells is not linked to the mechanism of activation of cytokine secretion and/or proliferation.Abbreviations used IFN
interferon
- IL
interleukin
- PBL
peripheral blood leukocytes
- PE
phycoerythrin
- PE-GAM
PE-conjugated Fab2 goat anti-mouse IgG
- NK
natural killer
- NRS
normal rabbit serum
- TNF
tumor necrosis factor
- FCS
fetal calf serum
- FITC
fluorescein isothiocyanate
- PBS
phosphate-buffered saline
- MACS
magnetic cell sorting
- ELISA
enzyme-linked immunosorbent assay
- BSA
bovine serum albumin
- PKC
protein kinase C
- mAb
monoclonal antibody
- PBMC
peripheral blood mononuclear cells
- BCLL
B-chronic lymphocytic leukemia
- E
effector
- T
target 相似文献
107.
We often see perilobular necrosis of the pancreas in patients with liver disease at autopsy. This study was undertaken to determine the frequency and the mechanism of development of pancreatic perilobular necrosis in patients with liver disease. Pancreatic perilobular necrosis was seen in 21 per cent of 261 autopsied patients: in 41 per cent of 73 autopsied patients with liver disease and in 13 per cent of 188 autopsied patients without liver disease. Moreover, splanchnic congestion was present in 90 per cent of 30 pancreatic perilobular necrosis patients with liver disease. These data indicate that patients with liver disease develop perilobular necrosis of the pancreas more often than patients without liver disease, and that the high frequency may be a sequela of splanchnic congestion; that is, congestion of the pancreas and endotoxaemia due to congestion of the gut. 相似文献
108.
兔激素性股骨头坏死的血液流变学改变 总被引:3,自引:0,他引:3
目的 探讨血液流变学指标在激素性股骨头坏死过程中的变化规律及其作用。方法 20只兔随机分成2组,每组10只。A组(激素性股骨头坏死动物模型组):间隔24h耳缘静脉内2次注射大肠杆菌内毒素,每次40μg/kg,注射内毒素后注射醋酸泼尼松龙20mg/kg。B组(正常对照组)。两组分别在注射后24h、72h、7d、14d 及21d,进行血浆黏度、全血黏度、血小板计数及血脂测定,21d取股骨头和肝脏行病理组织学观察。结果 A组用药后24h血浆黏度、全血黏度升高,血脂升高(P<0.01)血小板计数减少(P<0.01),用药后72h、7d、14d 及21d,持续异常,与B组相比差异显著。A组21d时病理切片见股骨头骨细胞和肝细胞变性、坏死。结论 在激素性股骨头坏死动物模型中,血液流变学指标异常在引起血栓前状态,形成血栓导致骨坏死过程中可能发挥了重要作用。 相似文献
109.
Cytokine profile in systemic lupus erythematosus,rheumatoid arthritis,and other rheumatic diseases 总被引:19,自引:0,他引:19
Mansour Al-Janadi Suliman Al-Balla Abdullah Al-Dalaan Syed Raziuddin 《Journal of clinical immunology》1993,13(1):58-67
We investigated serum levels of interleukin-6 (IL-6), interferon-gamma (IFN-), and tumor necrosis factor alpha (TNF) from patients with systemic lupus erythematosus (SLE) and its various clinical manifestations of disease and from patients with rheumatoid arthritis (RA) and other rheumatic diseases. The serum levels of IL-6 and IFN- were highly elevated from patients with SLE associated with lymphadenopathy (LN) or nephrotic syndrome (NS). On the contrary, the serum levels of TNF were elevated from most patients with SLE associated with thrombocytopenia (TP). However, serum levels of TNF were in the normal range from patients with SLE associated with NS, LN, or central nervous system disease. Of interest, patients with SLE associated with humoral immunodeficiency disorder, hypogammaglobulinemia, had highly elevated levels of serum IL-6. The concanavalin A-stimulated mononuclear cells (MNC) of patients with SLE associated with TP secreted highly elevated levels of TNF compared to other patient groups. We suggest that abnormal production of various cytokines in SLE is an intrinsic defect of MNC and the immune system that may be the key element for a variety of clinical manifestations of this disease. 相似文献
110.
Juan C. Rueda Luis Ortega Jesus M. Argüello Antonio J. Torres Ignacio Landa Jose L. Balibrea 《Virchows Archiv : an international journal of pathology》1992,420(2):117-120
Summary Retrograde injection of 5% sodium taurocholic acid (TA) in Wistar rat pancreatic duct is followed by acute pancreatitis, resulting
in 100% mortality within 36 h. Biochemical determinations show raised levels of amylase in ascites and blood. Necrosis has
been measured using seven morphometric characteristics of pathological changes that add precise information on the type and
extension of the pancreatic lesion. The percentage of necrotic tissue (by area) seems to be the most objective parameter.
Necrosis appears 6 h after TA infusion, being 5.77% in extent after 12h, 14.9% after 24 h and animals die with an area of
29.5% necrosis. This experimental model seems to one in which physiopathological and therapeutic trials on acute pancreatitis
may be camed out. 相似文献