VK_3诱导悬浮培养的胡萝卜细胞凋亡

VK_3是一种醌类物质,在体内通过氧化还原产生超氧化自由基。我们的实验发现,VK_3对悬浮培养的胡萝卜细胞及原生质体有致死作用。这种作用是浓度依赖性的。100—800μmol/L的VK_3能引起10%—33%的细胞死亡。当VK_3浓度达到1mmol/L时,死亡率达到100%。DNA电泳分析发现,600和800μmol/L的VK_3处理过的细胞和原生质体产生大小为180bp整数倍的梯状条带。而在更高或更低浓度的处理中则没有观察到这种条带。用TUNEL方法检测,在400—800μmol/L浓度的处理中观察到细胞核DNA的断裂。而在更高或更低浓度的处理中则没有观察到这种断裂。由此我们推测,适当浓度的VK_3能诱导胡萝卜细胞及原生质体凋亡。     

Muscle injection of rAAV/mFIX to secrete clotting factor IX corrects the hemorrhagic tendencies in hemophilia B mice

Recombinant AAV particles of high titer (>1013 virus genome/mL) were prepared according to the rHSV/AAV helper virus method. After intramuscular injection of viral vectors in the hind limb, a sustained elevated level (>370 ng/mL) of murine FIX expression in the plasma of hemophilia B mouse was detected and persisted for more than 350 days. The biological activity reached 30% of normal levels, and bleeding symptoms in the treated mice were significantly alleviated. No anti-FIX antibody (inhibitor) was detected, though anti-AAV antibodies were found at a very low level after single injection. Repeated injection with rAAV/mFIX led to a variation in anti-AAV antibody levels between the two groups which had received different doses. Results from tissue analysis confirmed the skeletal muscle as the origin for circulating functional mFIX. Our results suggest that AAV-mediated gene transfer offers a promising method of gene therapy for hemophilia B.     

羟自由基诱导烟草细胞凋亡

用适当浓度组合的硫酸亚铁和过氧化氢反应以产生羟自由基来处理烟草悬浮细胞,首次观察到了细胞中染色质凝缩、边缘化、细胞核解体等典型的细胞凋亡的形态学特征;在ＤＮＡ 琼脂糖凝胶电泳图谱上观察到因核ＤＮＡ 有规则地在核小体间被降解而产生的阶梯状条带;末端脱氧核糖核酸转移酶介导的３’ＯＨ 末端标记法（ｔｅｒｍｉｎａｌ ｄｅｏｘｙｎｕｃｌｅｏｔｉｄｙｌ ｔｒａｎｓｆｅｒａｓｅ （ＴｄＴ）ｍｅｄｉａｔｅｄ ｄＵＴＰ ｎｉｃｋｅｎｄｌａｂｅｌｉｎｇ,ＴＵＮＥＬ） 检测结果为阳性。这些实验表明,羟自由基确能诱导烟草细胞凋亡。     

VK3诱导悬浮培养的胡萝卜细胞凋亡

Menadione (VK3), a quinone that undergoes redox cycles leading to the formation of superoxide radicals, was found to induce cell death in suspension culture of carrot cells. The effect of menadione was in a dose-dependent manner. 100-800 mumol/L menadione caused 10-33 percent cell death. When concentration of menadione reached 1 mmol/L, 100 percent of cell death was observed. DNA cleavage, a hallmark of apoptosis was further studied. DNA ladders were observed in cells treated with 600 and 800 mumol/L menadione but not with lower concentration treatments where only very low percentage of cell death was found. There was no DNA ladders in the cells treated with 1 mmol/L menadion indicating that necrosis may occur. In situ detection of nuclear DNA fragmentation by TUNEL reaction revealed fragmented nuclear DNA in cells treated with 100-800 mumol/L menadion but not in cells treated with 1 mmol/L menadione.     

用TUNEL法检测植物原生质体的凋亡

TUNEL是近年来发展的一种对凋亡细胞进行原位检测的方法,可以特异性地标记完整的凋亡细胞核或凋亡小体的染色体3'_OH断裂末端,但在植物细胞中的应用还不多。本文报道应用TUNEL法检测胡萝卜原生质体的凋亡,并与DNA电泳、彗星电泳等方法进行了比较,结果表明它是一种适用于植物原生质体凋亡检测的灵敏度较高的方法。     

Muscle injection of rAAV/mFIX to secrete clotting factor IX corrects the hemorrhagic tendencies in hemophilia B mice

Hemophilia B is an X-linked disorder caused by the deficiency of clotting factor IX (FIX). Compared with conventional blood transfusion treatment, gene therapy offers a more attractive approach to achieve the goal of prophylactic hemostasis without the extreme costs, infectious and thrombotic risks, and the need for repeated and frequent injections of factor IX concentrates. Since 1987, our lab has conducted study of gene therapy for hemophilia B. In 1991, clinical trials involving four pa…     

腺相关病毒介导的小鼠IX因子在血友病B小鼠体内表达研究

通过重组HSV/AAV辅助病毒方法制备出高滴度(>10~(12))的重组AAV/mFⅨ病毒颗粒,并注射到血友病B小鼠的后肢骨骼肌中,获得了稳定的高水平小鼠Ⅸ因子表达(>370ng/mL),持续时间超过350d。治疗组小鼠体内的Ⅸ因子活性达到正常值的30％,而且出血症状得到显著改善。在小鼠血浆中未发现抗Ⅸ因子的中和抗体,第1次注射后抗AAV抗体的水平也非常低。重复注射AAV/mFⅨ病毒后,不同剂量组的小鼠体内的抗AAV抗体出现了不同的结果。组织分析结果证实了血浆中有功能的FⅨ因子确实来源于骨骼肌。以上结果显示,AAV介导的基因转移是血友病B基因治疗的极有前途的方法。     

CSN4基因干扰对乳腺癌MDA-MB-231细胞增殖和凋亡的影响

乳腺癌目前是危害女性常见的恶性肿瘤,研究发现COP9复合体中的各个亚基与恶性肿瘤的发生发展密切相关,且CSN4亚基对整个复合体具有很重要的调节作用。为探讨CSN4基因在乳腺癌细胞中的生物学功能及其分子作用机制,本研究首先在乳腺癌细胞MDA-MB-231中,成功建立了慢病毒介导的CSN4基因的干扰表达体系,并通过细胞表型实验、CCK8实验和细胞克隆形成实验证实CSN4基因表达的干扰能显著抑制乳腺癌MDA-MB-231细胞的增殖速率和克隆形成能力。流式细胞检测结果表明,干扰CSN4的表达能显著增加Sub G_1期乳腺癌MDA-MB-231细胞比例;凋亡检测结果表明,干扰CSN4的表达能显著增加早期凋亡和晚期凋亡细胞的比例,这证明干扰CSN4的表达能够促进乳腺癌细胞凋亡。最后,通过Western blot实验证实CSN4能调控CDK6和Caspase3蛋白的表达,激活Caspase3切割PARP,揭示CSN4可调控CDK6和Caspase3的表达从而影响乳腺癌细胞的增殖和凋亡。本研究结果进一步加深了人们对乳腺癌细胞凋亡和细胞生长的分子机制的认识,同时也进一步揭示了CSN4在肿瘤生物学中的作用和机制。     

腺相关病毒介导的小鼠Ⅸ因子在血友病B小鼠体内表达研究

通过重组HSV/AAV辅助病毒方法制备出高滴度(>10¹²)的重组AAV/mFⅨ病毒颗粒, 并注射到血友病B小鼠的后肢骨骼肌中, 获得了稳定的高水平小鼠Ⅸ因子表达(>370 ng/mL), 持续时间超过350 d. 治疗组小鼠体内的Ⅸ因子活性达到正常值的30%, 而且出血症状得到显著改善. 在小鼠血浆中未发现抗Ⅸ因子的中和抗体, 第1次注射后抗AAV抗体的水平也非常低. 重复注射AAV/mFⅨ病毒后, 不同剂量组的小鼠体内的抗AAV抗体出现了不同的结果. 组织分析结果证实了血浆中有功能的FⅨ因子确实来源于骨骼肌. 以上结果显示, AAV介导的基因转移是血友病B基因治疗的极有前途的方法.