哺乳动物胸腺器官发育及调控

胸腺为T细胞的发育、分化成熟及功能的获得提供重要而复杂的微环境。在胸腺微环境的作用下,T细胞发育成具有自身免疫耐受及MHC限制性的成熟淋巴细胞。T细胞分化成熟过程需要胸腺细胞与起源于胚胎第3咽囊的胸腺上皮细胞(Thymic epithelial cells,TECs)的相互作用。对胸腺器官三维组织结构的建立、胸腺前体细胞的迁入及胸腺的发育等过程的认识,有助于我们对胸腺器官形成的理解,也为胸腺发育缺陷相关疾病的预防及治疗提供重要依据。     

Immunostimulatory properties of a novel polyphosphoramidate based on stearyl tyrosine

The immunostimulatory property of a synthetic polyphosphoramidate based on stearyl tyrosine (PPST) is described. The immunostimulatory activity of this negatively charged polymer was investigatedin vitro through examining the effect on the mitogen-induced lymphocytes proliferation by a tetrazolium-based colormetric assay and also through studying the primary plaque-forming cells (IgM PFC) responses of Balb/c mice after the intraperitoneal (i.p.) injection of the polymer with sheep red blood cells (SRBC). PPST exhibits specific and high immunostimulatory activityin vitro by the stimulation on lipopolysaccharide(LPS)-induced murine B-cells proliferation, which is probably due to the interaction between the polymer with LPS-responding B lymphocytes. This polymer also makes a significant increase of single antibody producing cells. The result shows that the stimulation rate to IgM PFC response of Balb/c mice achieved 77.9% (p<0.01) when 160 mg/kg of PPST was injected 4 h before with SRBC. Supported by the National Natural Science Foundation of China and Research Laboratories of Natural and Biomimetic Drugs of Beijing Medical University Zhuo Renxi: born in Feb. 1931, Professor     

Enhancement of the cytogenetic efficacy of the antitumor agent bleomycin by the calcium and calmodulin antagonist fendiline

Summary The induction of chromosome aberrations (dicentric and ring chromosomes) in human lymphocytes by the antitumor agent bleomycin is synergistically enhanced when bleomycin is applied together with the calcium antagonist fendiline (Sensit^®).     

模拟微重力大鼠T淋巴细胞发育异常的初步研究

对模拟空间微重力条件下大鼠T细胞发育受阻的神经免疫调节机理进行初步探究.采用流式细胞检测技术测定模拟微重力大鼠胸腺中不同发育阶段T淋巴细胞的数量变化,用ELISA法测定胸腺组织中去甲肾上腺素(NE)和内源性糖皮质激素(GC)的含量.结果表明模拟微重力模型大鼠出现明显胸腺萎缩(p<0.05),CD3⁺CD4⁺CD8^-和CD3⁺CD4^-CD8⁺T细胞数量明显减少(p<0.05);模拟微重力大鼠胸腺中NE和GC含量有升高的趋势.模拟微重力大鼠胸腺中发生了从双阳性T细胞向单阳性T细胞的发育阻滞,这种异常可能与神经内分泌免疫调控相关.     

小鼠胸腺的结构、功能与日龄的关系

目的　探讨小鼠胸腺的结构、功能变化与日龄的关系。方法　以不同日龄的小鼠为研究对象,采用免疫组织化学方法观察胸腺细胞的凋亡情况和胸腺中T淋巴细胞的数目变化。结果　不同日龄小鼠均可见胸腺细胞凋亡,新生小鼠、第1 4、2 8d小鼠组间无明显区别(P >0 0 5 ) ,日龄4 2、5 6d小鼠相比于幼龄小鼠胸腺细胞凋亡显著增多(P <0 0 5 ;P <0 0 1 ) ,且T细胞数目明显减少(P <0 0 5 )。结论　幼龄小鼠胸腺功能已成熟,并不随小鼠的发育而增强。至日龄4 2d后,胸腺细胞凋亡明显加快,胸腺萎缩,成熟T细胞减少,功能降低。     

鹰嘴豆芽素A对小鼠T淋巴细胞体外活化增殖和细胞周期的影响

目的:研究黄酮类化合物鹰嘴豆芽素A(biochanin A,bioA)对小鼠T淋巴细胞的活化增殖和周期的影响.方法:运用双色荧光抗体染色技术结合流式细胞术分析bioA对小鼠T淋巴细胞在多克隆刺激剂(ConA)刺激下早期活化抗原CD69表达的影响;运用羧基荧光素乙酰乙酸(carboxyfluorescein diacetate,succinimidyl ester,CFDA-SE)标记技术结合流式细胞术,分析T淋巴细胞增殖相关指数;用碘化丙锭(propidium iodide,PI)染色分析T淋巴细胞细胞周期变化.结果:终浓度为25、50μmol/L的bioA对ConA刺激下的T淋巴细胞早期活化抗原CD69表达具有明显的抑制作用(P＜0.05),50 μmol/L抑制达到峰值;CFDA-SE染色法显示,25、50 μmol/L bioA对ConA诱导的T淋巴细胞增殖作用具有显著的抑制作用(P＜0.05);终浓度为5、25、50 μmol/L的bioA能够使ConA刺激的T淋巴细胞滞留于G0/G1期,减少处于S期和G2/M期细胞数.结论:BioA对小鼠T淋巴细胞的活化增殖和周期具有明显的抑制作用.     

烷基酚类化合物对人外周血淋巴细胞DNA损伤的研究

烷基酚类化合物是一类污染十分广泛 ,且具有诱发某些肿瘤的环境内分泌干扰物 .应用单细胞凝胶电泳技术 ,研究了烷基酚类化合物对人外周血淋巴细胞DNA的损伤作用 .实验结果表明 ,9种烷基酚类化合物均能引起不同程度的DNA损伤 ,并呈现出剂量效应关系 .其高剂量组与对照组相比 ,均有极显著性差异 (p <0 .0 1) .实验结果亦表明 ,DNA的损伤程度与化学结构有一定的关系