抗Aβ42单链抗体对阿尔茨海默病小鼠脑中淀粉样沉积的改善作用

发布时间：2018-05-04 03:10

本文选题：阿尔茨海默病 + β淀粉样蛋白　；参考：《中国老年学杂志》2017年13期

【摘要】：目的探讨以β淀粉样蛋白(Aβ)42为靶抗原筛选人源天然单链抗体(sc Fv)噬菌体抗体库中的特异性抗体对阿尔茨海默病(AD)模型鼠中淀粉样沉积的影响。方法以Aβ42抗原包被免疫管,对人源天然sc Fv噬菌体抗体库进行筛选,经过3轮吸附-洗脱-扩增淘选富集,制备单克隆噬菌体抗体颗粒,用酶联免疫吸附(ELISA)法检测sc Fv的结合活性,得到一株阳性克隆sc Fv23。采用Western印迹和免疫组化的方法检测了sc Fv23与Aβ42单体、寡聚体、纤维和鼠脑中Aβ沉积的结合能力。并通过甲氮甲唑蓝(MTT)法检测sc Fv23对Aβ42寡聚体引起细胞毒性的影响,同时采用硫黄素-T荧光法(Th T-F)测定sc Fv23对Aβ42聚集形成纤维的影响。最后,通过体内实验检测了sc Fv23对AD鼠模型脑中Aβ42沉积的影响。结果通过对人源天然sc Fv噬菌体抗体库进行筛选得到一株与Aβ42具有高亲和力的克隆sc Fv23。实验发现sc Fv23可以特异性识别Aβ42寡聚体,纤维聚集体和鼠脑中Aβ42沉积,但是不能与Aβ42单体特异性结合。根据体外实验结果,sc Fv23可以有效抑制Aβ42寡聚体所诱导的细胞死亡,并且sc Fv23可以抑制Aβ42纤维聚集体的形成。体内实验结果发现,sc Fv23可以有效清除AD鼠模型中Aβ42沉积。结论通过噬菌体文库筛选得到的sc Fv23能够特异性识别脑组织中的淀粉样沉积,并且有效抑制转基因鼠中淀粉样沉积的形成。体外实验表明sc Fv23可以有效抑制Aβ42寡聚体所诱导的细胞毒性。特异性识别Aβ42的sc Fv可能会成为治疗AD的一种有效策略。
[Abstract]:Objective to study the effect of specific antibodies from human natural scFv phage antibody library on amyloid deposition in mice with Alzheimer's disease (AD) model. Methods A 尾 42 antigen was used to coat the immune tube to screen the natural Sc Fv phage antibody library. The phage antibody particles were prepared by three rounds of adsorption, elution, amplification and enrichment. Enzyme linked immunosorbent assay (Elisa) was used to detect the binding activity of sc FV, and a positive clone sc Fv23 was obtained. The binding ability of sc Fv23 to A 尾 42 monomer, oligomer, fiber and A 尾 deposition in brain was detected by Western blot and immunohistochemistry. The effects of SC Fv23 on cytotoxicity induced by A 尾 42 oligomer were detected by methazolyl methazolium (MTT) method, and the effect of SC Fv23 on the aggregation of A 尾 42 fibers was determined by thiolin-T fluorescence assay (Th T-F). Finally, the effects of sc Fv23 on A 尾 42 deposition in the brain of AD rats were investigated in vivo. Results A clone sc Fv23 with high affinity to A 尾 42 was obtained by screening human natural sc Fv phage antibody library. It was found that sc Fv23 could specifically recognize A 尾 42 oligomers, fibrous aggregates and A 尾 42 deposits in the brain, but could not bind to A 尾 42 monomers. According to the results of in vitro experiments, Sc Fv23 could effectively inhibit the cell death induced by A 尾 42 oligomer, and SC Fv23 could inhibit the formation of A 尾 42 fiber aggregation. The results showed that Sc Fv23 could effectively eliminate A 尾 42 deposition in AD mice. Conclusion sc Fv23 screened by phage display library can specifically recognize amyloid deposition in brain tissue and inhibit the formation of amyloid deposition in transgenic mice. In vitro experiments showed that sc Fv23 could effectively inhibit the cytotoxicity induced by A 尾 42 oligomer. Sc FV specific recognition of A 尾 42 may be an effective strategy in the treatment of AD.
【作者单位】：广州医科大学附属第一医院神经内科;广东番禺中心医院神经内科;广州医科大学附属第一医院检验科;广州医科大学临床技能中心;
【分类号】：R749.16

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