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91.
Chromosome aberrations in B-cell chronic lymphocytic leukemia: reassessment based on molecular cytogenetic analysis 总被引:13,自引:0,他引:13
Döhner H Stilgenbauer S Döhner K Bentz M Lichter P 《Journal of molecular medicine (Berlin, Germany)》1999,77(2):266-281
In B-cell chronic lymphocytic leukemia (B-CLL) clonal chromosome aberrations are detected in approximately 40–50% of tumors
when using conventional chromosome banding analysis. Most studies find trisomy 12 to be the most frequent chromosome aberration,
followed by structural aberrations of the long arm of chromosomes 13 and 14. Trisomy 12 and the ”14q+” marker are associated
with shorter survival times, while the patients with 13q abnormalities have a favorable outcome, similar to those with a normal
karyotype. The development of molecular cytogenetic techniques has greatly improved our ability to detect chromosome aberrations
in tumor cells. Using fluorescence in situ hybridization, chromosome aberrations can be detected not only in dividing cells
but also in interphase nuclei, an approach referred to as interphase cytogenetics. The prevalence of specific aberrations in B-CLL is currently being reassessed by interphase cytogenetics. By far the most
frequent abnormality are deletions involving chromosome band 13q14, followed by deletions of the genomic region 11q22.3-q23.1,
trisomy 12, deletions of 6q21-q23, and deletions/mutations of the TP53 tumor suppressor gene at 17p13. The evaluation of the true incidence of these aberrations now provides the basis for more
accurate correlations with clinical characteristics and outcome. Deletions/mutations of the TP53 gene have been shown to be associated with resistance to treatment and to be an independent marker for poor survival. 11q
deletions have been associated with extensive nodal involvement, rapid disease progression, and short survival times. Whether
trisomy 12, 13q14, and 6q deletions have a prognostic impact awaits further study. The application of these molecular cytogenetic
techniques will also contribute to the identification of the pathogenetically relevant genes that are affected by the chromosome
aberrations in B-CLL.
Received: 2 February 1998 / Accepted: 31 March 1998 相似文献
92.
Interleukin-2 (IL-2), secreted principally by activated helper T-cells, plays a pivotal role in the generation and regulation
of the immune response. The various biologic functions of IL-2 have been the focus of intensive study over the years and have
been well worked out. By contrast, an understanding of the intracellular signals coupled to the IL-2 receptor and responsible
for mediating IL-2 effects in T-cells is far less developed, and the role that protein kinase C (PKC) may play in the various
cellular responses to IL-2 receptor activation is unclear. In this article we will discuss IL-2, its receptors, and IL-2 signal
transduction in relation to the physiological roles PKC activation may play in IL-2-mediated activation of T-cells and other
hematopoietic cells. 相似文献
93.
The pro-inflammatory cytokine interleukin-1β (IL-1β) is released by cells during injury and stress, and increased neuronal expression of IL-1β is a feature of age-related neurodegeneration. We have recently reported that IL-1β has a biphasic effect on the K+-induced rise in intracellular Ca2+ concentration ([Ca2+]i) in cortical synaptosomes, exerting an inhibitory effect on the K+-induced rise in [Ca2+]i at lower (3.5 ng/mL) concentrations and a stimulatory effect on the K+-induced rise in [Ca2+]i at higher (100 ng/mL) concentrations. In the present study, we observed that the K+-induced rise in [Ca2+]i was inhibited to a similar extent by the lower concentration of IL-1β in cortical synaptosomes prepared from young (3-month-old), middle-aged (12-month-old) and aged (24-month-old) rats. In contrast, cortical synaptosomes prepared from the aged rats exhibited an increased susceptibility to the higher concentration of IL-1β, resulting in a marked elevation in [Ca2+]i. We propose that the age-related increase in neuronal concentration of IL-1β promotes a dramatic elevation in [Ca2+]i following membrane depolarization, thereby altering Ca2+ homeostasis and exacerbating neuronal vulnerability to excitotoxicity. 相似文献
94.
Jan K. Lacki Kamilla Klama Stefan H. Mackiewicz Urszula Mackiewicz Wolfgang Müller 《Inflammation research》1995,44(1):24-26
In order to evaluate the relationship between serum concentrations of interleukin-10 (IL-10), IL-6, and acute phase proteins in rheumatoid arthritis (RA) patients treated with methotrexate (MTX) or intramuscular gold (IMG) we determined IL-10, IL-6, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP) and alpha-1-antichymotrypsin (ACT) in the sera of 35 RA patients. IL-10 and IL-6 levels were evaluated using an enzyme-linked immunoassay (ELISA). AGP and ACT level were measured using rocket immunoelectrophoresis. IL-10 serum level was not increased in RA patients as compared to controls (58.7 ± 18.1 pg/ml vs. 57.2 ± 11.9 pg/ml). IL-6 level was significantly elevated (91.6 ± 46.9 pg/ml vs. 45 ± 19 pg/ml, p < 0.05). CRP was significantly increased as compared to healthy controls (35 ± 19 mg/l vs. 3 ± 2 mg/l, p < 0.05). Patients treated with MTX or IMG presented an increased level of IL-10 and decreased amounts of IL-6, as compared to those treated with NSAID only. However, only changes between patients treated with IMG and NSAID were found to be statistically significant. A good negative correlation between IL-10 and IL-6 serum level was found (r = –0.75, p < 0.05). A positive significant correlation between IL-6 serum level and CRP (r = 0.62, p < 0.05), AGP (r = 0.78, p < 0.05) and ACT (r = 0.45, p < 0.05) was established. On the other hand, a negative correlation between IL-10 and serum level of CRP (r = –0.76, p < 0.05), AGP (r = –0.64, p < 0.05) and ACT (r = –0.38, p < 0.05) was also observed. Moreover, these relationships were maintained when patients treated with MTX, IMG, or NSAID were analyzed independently. According to the data thus far obtained, it seems that IL-10 decreases IL-6 production, and thereby indirectly affects the acute phase response, decreasing CRP, AGP, and ACT concentration in RA patients.Abbreviations ACT
-1-antichymotrypsin
- AGP
1-acid glycoprotein
- APP
acute phase protein
- CRP
C-reactive protein
- CSF
colony stimulating factor
- IFN
interferon
- IL
interleukin
- IMG
intramuscular gold
- MTX
methotrexate
- NSAID
non-steroidal anti-inflammatory drug
- RA
rheumatoid arthritis 相似文献
95.
遗传过敏性皮炎患者血清IL—4水平与IgE的关系 总被引:4,自引:0,他引:4
钱起丰 《中华微生物学和免疫学杂志》1995,15(5):312-314
采用酶联免疫技术检测21例遗传过敏性皮炎患者血清白细胞介素4(IL-4)及IgE水平。实验结果发现,AD患者血清IL-4水平比正常人显著增高,并且与IgE密切相关。说明AD的发病与IL-4产一失调,从而导致B细胞合成IgE增加有关。人IL-4酶联免疫检测具有敏感、特异、简便、快速及结果可靠等特点。 相似文献
96.
应用mRNA麦胚无细胞体外转译体系,动态地观察了人参三醇皂甙(PTGS)对人淋巴结细胞IL-5基因表达的促进效应。结果表明,PTGS可以明显促进PHA活化人淋巴结细胞分泌IL-5,最大促进效应可达66.67%。PTGS+PHA共刺激后人淋巴结细胞浆IL-5 mRNA转译IL-5的量明显高于单纯PHA组,最大促进效应40%。上述结果首次证明PTGS对IL-5的促诱生效应是通过调节IL-5基因表达而实现的。 相似文献
97.
The focus of our research is to understand the immune response to foreign tissue. We believe that adichotomy exists within
the immune response to an allograft such that part of the response is dedicated to the protection of the graft. Nevertheless,
in a dominantly graft-aggressive environment, rejection typically ensues. In this article, we describe models that have been
set up to test directly the ability of potentially protective aspects of the immune response to prevent allograft rejection.
We discussour data in the context of a growing body of exciting and often controversial literature. 相似文献
98.
Martin C Al-Qaoud KM Ungeheuer MN Paehle K Vuong PN Bain O Fleischer B Hoerauf A 《Medical microbiology and immunology》2000,189(2):67-74
The pathways conferring immunity to human filariases are not well known, in part because human-pathogenic filariae do not
complete a full life cycle in laboratory mice. We have used the only fully permissive infection of mice with filariae, i.e.,
infection of BALB/c mice with the rodent filarial nematode Litomosoides sigmodontis. Our previous results showed that worm development is inversely correlated with Th2 cytokine production and eosinophilia.
The scope of the present study was to directly elucidate the role of interleukin-5 (IL-5) and eosinophils in controlling the
development of L. sigmodontis after vaccination and in primary infection. BALB/c mice immunized with irradiated third-stage larvae (L3) were confirmed
to have elevated IL-5 levels as well as high subcutaneous eosinophilia and to attack and reduce incoming larvae within the
first 2 days, resulting in 70% reduction of worm load. Treatment of vaccinated mice with anti-IL-5 antibody (TRFK-5) suppressed
both blood and tissue eosinophilia and completely abolished protection. This demonstrates, for the first time in a fully permissive
filarial infection, that IL-5 is essential for protection induced by irradiated L3 larvae. In contrast, in primary-infected
mice, anti-IL-5 treatment did not modify filarial infection within the 1st month, most likely because during primary infection
IL-5-dependent mechanisms such as subcutaneous eosinophilia are induced too late to disturb worm establishment. However, there
is a role for IL-5 late in primary infection where neutrophil-dependent worm encapsulation is also under the control of IL-5.
Received: 30 March 2000 相似文献
99.
目的:了解分泌肽序列在HepG2细胞中对人内皮抑素基因(hEndostatin)的cDNA表达和分泌差异的影响。方法:构建不含hIL-2分泌肽序列的真核表达载体pBlast-hEndo质粒, 转染人的HepG2细胞株, 用RT-PCR的方法检测HepG2(pBlast-hIL2-hEndo), HepG2(pBlast-hEndo), HepG2(pBlast-Mcs)和HepG2中hEndostatin的mRNA表达水平, 及制备4种细胞的总蛋白和收集各自的培养上清, 进行Westernblot分析蛋白表达和分泌的差异。结果:发现HepG2(pBlast-hIL2-hEndo)中hEndostatin的mRNA的水平显著高于HepG2(pBlast-hEndo)。而仅在HepG2(pBlast-hIL-2-hEndo)的细胞总蛋白和上清, 及HepG2(pBlast-hEndo)的细胞总蛋白中检测到hEndostatin表达, 在其它各株细胞总蛋白及上清中, 未检测到hEndostatin。结论:hIL-2分泌肽序列能促进hEndostatin基因在HepG2细胞中表达及分泌。 相似文献
100.
白细胞介素-8研究进展 总被引:14,自引:0,他引:14
白细胞介素-8(IL-8)在趋化性细胞因子家族中属于C-X-C亚家族,IL-8是一个多种细胞来源的趋化性细胞因子,而且不同类型的细胞对不同的诱导剂的反应也不相同,因为由不同的实验室从不同的来源得到该因子,所以对于IL-8的许多不同的描述术语,对于IL-8的生理生化特性,目前已基本清楚,对于IL-8基因表达的调节,现认为主要是在转录水平的调控,并且发现其基因5′-侧翼区的AP-1,NF-кB及NF-IL-6结合位点是调节IL-8启动子功能的主要顺式作用元件,IL-8基因的表达需要这些元件之间高度的协同以达到有效的转录,IL-8受体则是一个由59KDa和67KDa亚单位组成的二聚体糖蛋白,存在于多种类型的细胞上,甚至包括一些不表达IL-8的细胞,IL-8的生物学活性并不表现出种族的特异性,IL-8可激活中性粒细胞,对T-淋巴细胞有趋化性并能刺激嗜碱性粒细胞,内皮细胞IL-8基因的表达除了受化学因子的调节外还受力学因素的影响,流体切应力诱导内皮细胞表达IL-8,可能在急性炎症和动脉粥样硬化的发生,发展过程中具有重要作用。 相似文献