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1.
目的:研究吗啡对不同淋巴细胞增殖的作用及纳洛酮的影响.方法:观察吗啡对未成熟的、静止的及活化的脾脏淋巴细胞体外增殖影响及纳洛酮的阻断作用.结果:吗啡(1×10~(-10)—1×10~(-6)mol L~(-1))能增加Con A诱导的T-细胞的增殖,1 μmol L~(-1)还能促进LPS诱导的B-细胞的增殖,同时这些增强作用都能被纳洛酮50μmol L~(-1)阻断,纳洛酮单独亦能促进活化T-细胞的增殖.而吗啡1×10~(-10)—1×10~(-5)mol L~(-1)对静止的脾脏淋巴细胞及Con A活化的胸腺淋巴细胞的增殖都无影响.但是吗啡1mmol L~(-1)能广泛抑制静止的、LPS活化的脾脏细胞及Con A活化的胸腺,脾脏淋巴细胞增殖,且都不能被纳洛酮阻断.结论:吗啡对活化T-和B-细胞的促进作用是由细胞表面的阿片受体介导的,此阿片受体随着淋巴细胞的成熟和活化而变化,而吗啡1 mmol L~(-1)对淋巴细胞增殖的抑制作用却不是由经典的阿片受体介导的.  相似文献   
2.
We report six Chinese boys with hypogammaglobulinaemia. All but one had very low or undetectable circulating B-lymphocytes, two had reversed CD4/CD8 ratios (in one of whom this later became normal), one had reduced lymphocyte proliferative responses to concanavalin A and pokeweed mitogen and three had deficient responses to OKT3. Generation of antibody-secreting cells in response to pokeweed mitogen was markedly defective in all patients. Co-cultures of purified lymphocyte subsets from the patients with those of normal donors revealed that in addition to B-cell deficiency seen in all patients, two had T-helper cell deficiency and two had T-suppressor cell hyperactivity. One of the latter patients was treated with cimetidine in an attempt to ablate histamine type 2 receptor-bearing suppressor cells: the absolute number of such cells was temporarily reduced but there was no concurrent correction of the functional hyperactivity. These studies point to the variable nature of T-regulatory cell deficiencies in hypogammaglobulinaemia.  相似文献   
3.
B细胞杂交瘤技术制备抗同种特异T细胞膜抗原单克隆抗体   总被引:1,自引:0,他引:1  
目的:为进一步分析TCV免疫诱导同种免疫反应低下的机制。方法:采用B细胞杂交瘤技术获得分泌单克隆抗体的杂交瘤细胞。结果:两次的细胞融合中共得到12株稳定分泌单抗的杂交瘤细胞,为分析抗体在TCV中的作用提供条件。结论:TCV免疫可引起抗TCV细胞抗体的产生,以同系免疫的方法得到的活化B细胞用于B细胞杂交生产单抗是可行的。  相似文献   
4.
CpG DNA functions via the toll-like receptor-9 (TLR-9) receptor, inducing B cell proliferation and promoting immunoglobulin production. B cell responses to CpG DNA-containing immune complexes could be important in chronic autoimmunity and immune responses to bacterial components. Therefore, we investigated the potential synergy of CpG DNA-stimulation with FcgammaR clustering (CFR) on splenic B cell activity. CFR-induced splenocyte proliferation was significantly increased compared to treatment with CpG DNA alone. While the levels of interleukin-10 (IL-10) were increased in CpG DNA-treated splenocyte cultures, particularly following FcgammaRII/III-clustering, CFR treatment reduced IL-6 levels. B-cell maturation in culture was enhanced by CFR. Indeed, the frequency of IgG expressing cells after stimulation with CpG DNA was increased and was even higher after CFR stimulation. Furthermore, the frequency of plasma cell precursors was markedly increased by stimulation with CFR. Late splenic B cell subsets, transitional type 2 (T2) and mature (M) B cells, responded strongly to CpG DNA with proliferation and the response was enhanced by FcgammaR-clustering. Immature transitional type 1 (T1) B cells showed distinctly lower proliferative response to CpG DNA and very small effects of FcgammaR-clustering, despite similar expression of Fcgamma-receptors by all B cell subsets. In conclusion, these data show synergistic impact of CpG DNA and simultaneous FcgammaR-clustering on B cell proliferation and differentiation.  相似文献   
5.
子宫内膜异位症患者免疫功能的变化   总被引:2,自引:0,他引:2  
目的 为了探讨子宫内膜异位症发病的免疫机制。方法 采用间接免疫荧光法对子宫内膜异位症患者外周血中的 T细胞亚群、 B 细胞, N K 细胞及 I L- 2 R+ 细胞进行检测,并采用酶联免疫双抗体夹心法对子宫内膜异位症患者外周血及腹腔液中的 T N F- α浓度进行了检测。结果 子宫内膜异位症患者外周血中 T 细胞亚群失衡、 B 细胞增多,外周血及腹腔液中的 T N F- α浓度显著升高。结论 外周血中 T 细胞亚群失衡、 B 细胞增多,腹腔液中 T N Fα浓度升高可能与子宫内膜异位症的发生,发展密切相关。  相似文献   
6.
石见穿酸性多糖SC4的结构特征和生物活性   总被引:5,自引:0,他引:5  
目的:研究从石见穿(Salvia chinensis)中得到的酸性多糖SC4的化学结构和生物活性.方法:利用化学和光谱方法分析了SC4的结构特征,并观察了SC4对淋巴细胞增殖的影响以及增强PC12细胞对抗H_2O_2造成的损伤的作用.结果:SC4的分子量为4.5×10~5,由Rha,Xyl,Ser,Gal和GalA组成,摩尔比为1.0:7.0:5.3:1.2:4.2.甲基化和~(13) C NMR进一步确定了SC4中各糖残基的连接方式.SC4能显著促进B淋巴细胞的增殖,增加小鼠脾重,增强PC12细胞对抗H_2O_2造成的氧化损伤的能力.结论:SC4为一多分枝的酸性多糖,其免疫活性的靶细胞为B淋巴细胞,并显著增强PC12细胞对抗H_2O_2造成的损伤的能力.  相似文献   
7.
目的:观察IgA肾病(IgA nephropathy,IgAN)患者腭扁桃体、外周血中记忆B细胞表达及腭扁桃体切除后外周血记忆B细胞表达的变化,了解腭扁桃体在IgAN发病机制中的作用,为IgAN的治疗提供理论依据。方法:选取28例经临床和肾脏病理检查确诊为IgAN的患者腭扁桃体及外周血作为观察组,将27例慢性扁桃体炎患者腭扁桃体及10例正常健康者外周血作为对照组。采用流式细胞术检测记忆B细胞在腭扁桃体及外周血B细胞的表达,并分析IgAN患者腭扁桃体切除前、后外周血记忆B细胞的变化。结果:记忆B细胞在IgAN患者腭扁桃体及外周血高表达,分别为5.72%±5.26%和4.92%±5.10%;腭扁桃体切除前、后外周血中记忆B细胞表达百分率分别为4.92%±5.10%和1.10%±0.65%,差异有统计学意义,且腭扁桃体切除后外周血记忆B细胞表达基本恢复到正常水平。结论:记忆B细胞表达的高低为IgAN的临床进展研究提供了依据。  相似文献   
8.
目的探讨系统性红斑狼疮(SLE)患者和健康者静脉血B淋巴细胞成熟抗原(BCMA)表达和CD138+浆细胞数量的差异。方法将40例SLE患者血液标本作为SLE组,30例健康人血液标本作为对照组,采用荧光定量实时聚合酶链反应及酶联免疫吸附测定(ELISA)技术检测BCMA的表达,流式细胞技术检测静脉血CD138+浆细胞数量。结果 SLE组患者静脉血中BCMA mRNA水平、蛋白含量以及CD138+浆细胞的数量明显高于对照组(P<0.05)。结论 SLE患者中浆细胞数量的增多可能与BCMA高表达相关。  相似文献   
9.
Purpose:?To analyse the role of in vitro radio-induced apoptosis of lymphocyte subpopulations as predictive test for late effects in cervical cancer patients treated with radiotherapy.

Methods and materials:?Ninety-four consecutive patients and four healthy controls were included in the study. Toxicity was evaluated using the Late Effects Normal Tissue-Subjective, Objective, Management, and Analytic (LENT-SOMA) scale. Peripheral blood lymphocyte subpopulations were isolated and irradiated at 0, 1, 2 and 8 Gy, and then collected 24, 48 and 72 h after irradiation. Apoptosis was measured by flow cytometry.

Results:?Radiation-induced apoptosis increased with radiation dose and time of incubation, and data fitted to a semi-logarithmic model defined by two constants: α (percentage of spontaneous cell death) and β (percentage of cell death induced at a determined radiation dose). Higher β values in cytotoxic T-lymphocytes (CD8) and bone cells (B-lymphocytes) were observed in patients with low bowel toxicity (hazard ratio (HR)?=?0.96, p?=?0.002 for B-cells); low rectal toxicity (HR?=?0.96, p?=?0.020; HR?=?0.93, p?=?0.05 for B and CD8 subpopulations respectively); low urinary toxicity (HR?=?0.93, p?=?0.003 for B-cells) and low sexual toxicity (HR?=?0.93, p?=?0.010 for CD8-cells).

Conclusions:?Radiation-induced CD8 T-lymphocytes and, for the first time, B-lymphocytes apoptosis can predict differences in late toxicity in cervical cancer patients.  相似文献   
10.
Alternate splicing of exons of the CD45 molecule generates multiple isoforms differing in their molecular weights (MWs). In B-lymphocytes the CD45RA isoform was previously shown to be expressed on glycoproteins with MWs of 220 and 205 kDa, while the CD45RO isoform was expressed on glycoproteins with MW of 180 kDa. The present study demonstrated that B cell lymphomas and activated B-cells contain CD45 molecules with a MW of 185 kDa that express the CD45RA and CD45RC specificities but neither the CD45RB nor the CD45RO specificities. 185 kDa CD45RA+ molecules were detected in B cell lymphoma B lines, in Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines, and in tonsillar B cells, but not in normal, unstimulated peripheral blood B cells. These molecules were not detected in neoplastic and normal T cells. CD45RA+ 185 kDa molecules were present in B cells from three non-Hodgkin's patients in leukemic phase were not detected in B lymphocytes of seven of nine CLL patients tested. Trypsin treatment eliminated only 220 kDa CD45RA+ molecules but not 185 kDa CD45RA+ molecules, indicating that the 185 kDa CD45RA+ molecules are not expressed on the cell surface. Pulse-chase experiments, and studies on the effects of tunicamycin, neuraminidase and O-glycosidase, indicated that the 185 kDa molecules are partially glycosylated CD45RABC molecules that constitute precursors of the 220 kDa molecules. The high concentration of 185 kDa CD45RA+ molecules in B lymphoma cells and in activated B cells seems to reflect a high turnover of CD45RA+ molecules characteristic for these cells.  相似文献   
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