外周血中检测AD生物标识物的可行性研究

A Method of Finding Bio-marker for Alzheimer’s disease in Peripheral Blood

阿尔茨海默病因损伤在中枢神经系统,早期明确诊断和有效合理治疗难度较大。早期发现,早期干预是公认的研究方向。近年来,外周血因容易获得和可重复的特点,成为寻找生物标识物的研究热点。然而,至今仍然没有稳定可行的方法。我们利用可获得的人血标本,采用不同的处理方法发现:1.抗淀粉样蛋白的区段(Aβ17-24和Aβ29-42)特异性抗体在AD病人中较高,可能成为AD病人的生物标识物;2.新鲜的血标本中Aβ不受离心速度的影响,所以可以用于定量分析。3.血浆标本的反复冻融可以明显降低Aβ的检测水平。因此,冻融的标本检测到的Aβ不能准确反应实际的量。本研究认为外周血中存在Aβ特异性的生物标识物,但要用适当的方法处理才能获得稳定可靠的结果。如果要得到更明确的结论,还有待在大样本研究后定论。

Alzheimer’s disease (AD) is characterized as the progressive damage in central nerve system, thus making the early precise diagnosis and effective intervention are nearly impossible. Therefore, it is well accepted as good strategies for early diagnosis and treatment. Peripheral blood system became the hot topic for biomarker discovery due to the easy access and possibility of repeatable sampling. There is no reliable blood marker for AD till now. Thus, we have conducted a study using some available blood samples in our lab to identify a way to explore a blood biomarker for AD. Surprisingly, we have identified that there are some anti-Aβ fragment specific antibody existed in AD blood after dissociation with low pH treatment, such as antibody against Aβ17-24 and Aβ29-42;We have also noticed that fresh blood sample is more proper to be used for Aβ level detection because it is not affected by the speed of centrifugation at all;Another interesting discovery is that freeze and thaw steps can significantly lower the level of detected Aβ compared to fresh sample. In conclusion, we have figured out a reliable and repeatable method to identify biomarker from peripheral blood for AD. However, our result is only based on the smaller sample size and need to be confirmed with larger sample size to be used as biomarker for AD.