美国科学家近日研究发现，一个感染土豆的病毒与和阿尔茨海默氏症（AD，Alzheimer's disease）有关的一个关键蛋白具有惊人的相似性。利用这一发现，科学家已经开始着手研制能够延缓或阻止阿尔茨海默氏症发作的抗体。相关论文发表在《生物化学杂志》（JBC）上。

      之前的实验表明，用β淀粉样蛋白接种疫苗产生抗体A能减缓AD进程，并改善认知能力，其原因可能是促进了淀粉质斑块的破坏。

      在最新的研究中，美国凯斯西储大学医学院的Robert Friedland和同事将一种土豆病毒（PVY，含有类淀粉质的蛋白）注入小鼠体内，之后4个月逐月增加注射量。结果发现，小鼠产生了很高的抗体水平，并在溶液和AD患者组织样本中均能附着在β淀粉样蛋白上。

     研究人员表示，土豆病毒很常见，不会对人体造成危害，它们将有助于研发对抗这种困扰人类多时的疾病。（生物谷Bioon.com）

生物谷推荐原始出处：

JBC，Vol. 283, Issue 33, 22550-22556，Robert P. Friedland，Michael G. Zagorski

Antibodies to Potato Virus Y Bind the Amyloid β Peptide

Robert P. Friedland1, Johnathan M. Tedesco, Andrea C. Wilson?, Craig S. Atwood?, Mark A. Smith||, George Perry**, and Michael G. Zagorski

Studies in transgenic mice bearing mutated human Alzheimer disease (AD) genes show that active vaccination with the amyloid β (Aβ) protein or passive immunization with anti-Aβ antibodies has beneficial effects on the development of disease. Although a trial of Aβ vaccination in humans was halted because of autoimmune meningoencephalitis, favorable effects on Aβ deposition in the brain and on behavior were seen. Conflicting results have been observed concerning the relationship of circulating anti-Aβ antibodies and AD. Although these autoantibodies are thought to arise from exposure to Aβ, it is also possible that homologous proteins may induce antibody synthesis. We propose that the long-standing presence of anti-Aβ antibodies or antibodies to immunogens homologous to the Aβ protein may produce protective effects. The amino acid sequence of the potato virus Y (PVY) nuclear inclusion b protein is highly homologous to the immunogenic N-terminal region of Aβ. PVY infects potatoes and related crops worldwide. Here, we show through immunocytochemistry, enzyme-linked immunosorbent assay, and NMR studies that mice inoculated with PVY develop antibodies that bind to Aβ in both neuritic plaques and neurofibrillary tangles, whereas antibodies to material from uninfected potato leaf show only modest levels of background immunoreactivity. NMR data show that the anti-PVY antibody binds to Aβ within the Phe⁴–Ser⁸ and His¹³–Leu¹⁷ regions. Immune responses generated from dietary exposure to proteins homologous to Aβ may induce antibodies that could influence the normal physiological processing of the protein and the development or progression of AD.