Pathogenesis and Treatment of beta-Galactosidase-Deficient Knockout Mice

β-半乳糖苷酶缺陷型基因敲除小鼠的发病机制和治疗

基本信息

批准号：
08457058
负责人：
SUZUKI Yoshiyuki
金额：
$ 4.93万
依托单位：
The Tokyo Metropolitan Institute of Medical Science
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

We succeeded in producing a mouse model of human G_<M1>-gangliosidosis by disruption of the murin beta-galactosidase gene, in order to analyze its pathogenesis and to try therapeutic approaches. Clinically the mutant mouse developed a progressive neurological disease 4 months after birth, manifesting itself as spastic diplegia. They died of severe nervous system dysfunction and extreme emaciation at 7-11 months of age. Neuronal cytoplasmic swelling due to storage of undigested substrates was observed in every area of the central nervous system, and the storage material appeared as membranous cytoplasmic bodies electron microscopically. This morphological change progerssed rapidly between 4 and 8 weeks of age. beta-Galactosidase activity was almost compeltely deficient in all tissues and body fluids examined.Biochemical analysis revealed a marked storage of ganglioside G_<M1> and its asialo derivative G_<A1>D in the central nervous system and some solid tissues, such as liver and spleen. G_<A1> storage was more remarkable as compared to that in human patients. These results indicated that this model animal is an authentic murine counterpart of human G_<M1>-gangliosidosis. However, there was no bone dysplasia or keratan sulfaturia in these disease mice. Urinary oligosaccharides showed an abnormal pattern on thin-layr chromatography which was similar to that in infantile G_<M1>-gangliosidosis. As an experimental trial, an adenovirus-mediated intravenous injection of beta-galactosidase cDNA was preformed into the mutant newborn mouse. The beta-galactosidase activity was expressed in the central nervous system 2 weeks after injection at the 10% normal lavel. At this stage, storage of G_<M1> and G_<A1> was significantly reduced as compared to animals without treatment. We concluded that the gene introduced in the vascular system has reached the central nervous system through the undeveloped blood-brain barrier in the neonatal period.

我们成功地通过破坏了穆林β-半乳糖苷酶基因来生成人类G_ <m1>的小鼠模型，以分析其发病机理并尝试使用治疗方法。临床上，突变小鼠出生后4个月就出现了一种进行性神经系统疾病，表现为痉挛性瘫痪。他们死于严重的神经系统功能障碍和7-11个月大时的极端消瘦。在中枢神经系统的每个区域都观察到由于未消化的底物的储存而导致的神经元细胞质肿胀，并且储存材料在膜细胞质体显微镜上以膜细胞质体显微镜显微镜显微镜显微镜显微镜显微镜显微镜。这种形态变化在4至8周龄之间迅速进行。 β-半乳糖苷酶活性几乎在所有检查的组织和体液中都缺乏缺陷。BioChemical分析显示，在中枢神经系统中，神经节苷脂G_ <m1>明显存储了神经节苷脂G_ <m1>及其ASIALO衍生物G_ <a1> d。与人类患者相比，G_ <A1>储存更为显着。这些结果表明，该模型动物是人类G_ <m1> - gangliosidoiss的正宗鼠类对应物。但是，这些疾病小鼠中没有骨发育异常或角sus。尿寡糖在薄膜色谱法上显示出异常的模式，与婴儿G_ <m1> - gangliosidisois中的含量相似。作为一项实验试验，将腺病毒介导的β-半乳糖苷酶cDNA的静脉注射注射被预形成突变的新生小鼠。 β-半乳糖苷酶活性在注射10％正常lavel后2周在中枢神经系统中表达。在此阶段，与未经治疗的动物相比，G_ <m1>和G_ <a1>的存储显着降低。我们得出的结论是，在新生儿时期，通过未开发的血脑屏障通过未开发的血脑屏障到达了中枢神经系统。