Jefferson Kimmel腫瘤中心的免疫學家的一項關于小鼠的類多發(fā)性硬化癥(MS)的研究表明,,中樞神經(jīng)系統(tǒng)(CNS)的血腦保護屏障(BBB)的受損傷程度與該疾病的嚴重程度有關。這項發(fā)現(xiàn)可以用于可能的MS治療并可以更好的了解BBB在疾病進程中的作用,。該成果發(fā)表在2007年4月9日的《美國國家科學院院刊》(PNAS)上,。
費城Thomas Jefferson大學Jefferson醫(yī)學院腫瘤生物學副教授D. Craig Hooper及Jefferson醫(yī)學院腫瘤生物學教授,、Jefferson神經(jīng)病毒學和生物技術基礎實驗室中心主任Hilary Koprowski等科學家希望找出導致實驗性變應性腦脊髓炎(EAE)發(fā)病及加重的因子,EAE常被用作MS自身免疫疾病研究的病理模型,。他們對不同種屬的具有某些與炎癥和免疫相關基因缺損的小鼠進行了研究,,觀察它們BBB的變化。他們發(fā)現(xiàn),,BBB損害及繼發(fā)的滲透性增加的程度都與疾病的嚴重程度相關,,但令人驚奇的是,幾乎每一例小鼠的基因改變都與其無關,。小鼠甚至在沒有預想中的自身免疫疾病的關鍵因子的情況下發(fā)生了EAE。
Dr. Hooper說:“我們已知在這些具有免疫系統(tǒng)某種成分缺失的小鼠中,,BBB的開放導致細胞和炎癥因子的釋放都如預想中對疾病的發(fā)展起到重要作用,。通透性改變程度與臨床疾病嚴重性相關的事實也表明,它是動物罹患疾病程度的一個重要決定因素,。這就強調了一個事實,,即血腦通透性改變對于象作為MS動物模型的EAE 這樣的CNS炎癥性疾病的發(fā)展是一個重要因素。”
Dr. Hooper說,,他的小組和其他研究者以前的研究都已經(jīng)證實,,BBB通透性對于MS的發(fā)展是至關重要的。他和他的同事為了研究這種通透性,,觀察了大量有某種基因缺損的小鼠,,缺失的基因都是對疾病發(fā)展有作用的各種免疫系統(tǒng)和炎癥細胞因子,,如NF kappa B, TNF-alpha, and αβγ干擾素。研究者對每一種屬小鼠都建了EAE模型,,并檢測了它們發(fā)病時的共同特點,。令人驚奇的是那些沒有發(fā)生EAE的小鼠,即使它們體內有各種免疫系統(tǒng)的重要缺損,,也仍然能夠發(fā)病,,盡管發(fā)病率有所差異。然而,,在αTNF免疫蛋白缺失的小鼠中,,即使BBB通透性增加往往也不發(fā)病,這使得科學家們懷疑其在疾病中的作用,。這也是所有動物通透性改變的第一個證據(jù),,也是通透性不一定始終與疾病一致的第一個暗示。
Dr. Hooper解釋說,,這些工作只是明確BBB在疾病中的作用這一長期目標的一部分,。關于導致BBB損傷的機制,這些結果告訴我們了很多,。在小鼠體內缺失的這些因子對于BBB的開啟并非必要,。
部分英文原文:
PNAS | March 27, 2007 | vol. 104 | no. 13 | 5656-5661
BIOLOGICAL SCIENCES / NEUROSCIENCE
Loss of blood–brain barrier integrity in the spinal cord is common to experimental allergic encephalomyelitis in knockout mouse models
Marzena J. Fabis*,, Gwen S. Scott*,, Rhonda B. Kean*,, Hilary Koprowski*,,, and D. Craig Hooper*,,,¶
*Center for Neurovirology, Department of Cancer Biology, Biotechnology Foundation Laboratories, and ¶Department of Neurological Surgery, Thomas Jefferson University, 1020 Locust Street, JAH 454, Philadelphia, PA 19107-6799
Contributed by Hilary Koprowski, February 12, 2007 (received for review January 26, 2007)
Experimental allergic encephalomyelitis (EAE) is an inflammatory demyelinating disease of the CNS that is used to model certain parameters of multiple sclerosis. To establish the relative contributions of T cell reactivity, the loss of blood–brain barrier (BBB) integrity, CNS inflammation, and lesion formation toward the pathogenesis of EAE, we assessed the incidence of EAE and these parameters in mice lacking NF-B, TNF-, IFN- receptors, IFN- receptors, and inducible nitric oxide synthase. Although increased myelin oligodendrocyte glycoprotein-specific T cell reactivity was generally associated with a more rapid onset or increased disease severity, the loss of BBB integrity and cell accumulation in spinal cord tissues was invariably associated with the development of neurological disease signs. Histological and real-time RT-PCR analyses revealed differences in the nature of immune/inflammatory cell accumulation in the spinal cord tissues of the different mouse strains. On the other hand, disease severity during the acute phase of EAE directly correlated with the extent of BBB permeability. Thus, the loss of BBB integrity seems to be a requisite event in the development of EAE and can occur in the absence of important inflammatory mediators.
gene knockout mice | multiple sclerosis