90%准确率!Nature突破成果:血液检测就能“认出”痴呆蛋白
2018/02/02
在过去的15年里,世界各地的科学家们一直在寻找一种简单的痴呆症血液检测方法。最近,Nature杂志发表了一项突破性成果:来自日本和澳大利亚的科学家小组开发了一种血液测试,可检测与阿尔茨海默症相关的毒性蛋白,且测试的准确率高达90%!


图片来源:Nature(DOI:10.1038/nature25456)

“目前为止,还没有一种可靠的方法,用来鉴定早期痴呆患者,所以,大多数临床试验都是招募临床症状已经很明显的人。在这时,与β-淀粉样蛋白有关的脑损伤已经发生,想逆转这种损伤可能太晚了。

这项新成果的通讯作者、分子生物学家Katsuhiko Yanagisawa说,“迄今为止,所有开发用于阻止阿尔茨海默症的候选药物在临床试验中都失败了,许多制药公司也放弃了这一领域。科学家们怀疑,这些失败可能是试验设计的问题,而不是被测试药物‘不行’。”

事实上,现在可用于鉴定大脑中β-淀粉样蛋白的两种方法是利用正电子发射断层扫描(positron-emission tomography)对大脑进行成像,或从脊髓中直接测定脑脊液中该蛋白的水平。尽管它们都被用来帮助招募患者进入最近的临床试验中,但这些测试,既昂贵又不舒服。


图片来源:网络

新方法结合两种现有技术

在这项新研究中,为了测量血液样本中“β-淀粉样蛋白”以及“由其衍生出的更大的蛋白”的碎片水平,Yanagisawa及其同事结合两种现有技术——免疫沉淀反应和质谱分析。结果显示,在2个独立的队列(cohort)中(包括在日本的122人以及在澳大利亚的252人),该测试的结果与通过脑成像和脊髓液分析所得出的结果相吻合。

值得一提的是,研究中每个队列所纳入的、年龄在60到90岁之间的个体,一些是健康的,一些认知能力有轻度损伤,还有一些是阿尔茨海默症患者。

科学家们表示,接下来,需要更大、更长期的研究来确认该测试“用于鉴定人类大脑中高水平β-淀粉样蛋白”的准确性。他们希望,药物开发者们能够利用这一测试,在患者大脑发生不可逆的损伤之前,就将这些人招募到临床试验中,从而使试验更可靠。同时,他们认为,该测试还具有相对更简单、更便宜的优势。


图片来源:网络

迄今为止看到的最好结果

对于这项研究成果,英国牛津大学的神经科学家Simon Lovestone说:“一开始,在血液中测定脑部疾病的这一想法显得不那么实际,但现在,我们离成功越来越近了。这篇论文提供了迄今为止我所看到的最好的结果。

在BBC的报道中,伦敦国王学院的Abdul Hye博士也表示:“这一研究具有重大意义,因为这是第一次有研究小组展示了血浆淀粉样蛋白与大脑和脑脊液之间的强烈关联。”

总结来说,作者们认为,这一血液检测有望实现更广泛的临床应用,以及更有效的人群筛查。最终,他们希望,利用这个便宜而简单的测试能够帮助开发更好的治疗老年痴呆症的方法。

参考资料:

Blood test finds toxic Alzheimer's proteins

Simple blood test spots dementia protein

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