長期以來醫(yī)學界認為,，人體免疫系統(tǒng)對已進入細胞內部的病毒束手無策,。但英國一項最新研究發(fā)現，一些抗體能夠隨病毒進入人體細胞內部,，并在細胞內一種蛋白質的作用下引發(fā)摧毀病毒的連鎖反應,，這一發(fā)現將有助于研發(fā)新的抗病毒藥物,。
位于英國劍橋的分子生物學實驗室等機構研究人員在新一期美國《國家科學院學報》上報告說，他們發(fā)現人體免疫系統(tǒng)生成的抗體在血液中遇到病毒后,，會一直附著其上,，即使一些病毒穿過細胞膜進入了人體細胞，抗體也仍然附著于這些病毒表面,。而人體細胞內部一種名為TRIM21的蛋白質會發(fā)現這些抗體,，并激活細胞內部的“垃圾處理系統(tǒng)”，在較短時間內將病毒消滅,。
研究人員已經開始嘗試在此基礎上研發(fā)新的抗病毒藥物,。初步實驗顯示，在增加細胞中TRIM21蛋白質的含量后,，細胞消滅病毒的能力大大提高,。（生物谷Bioon.com）
更多閱讀
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生物谷推薦英文摘要：
PNAS doi: 10.1073/pnas.1014074107
Antibodies mediate intracellular immunity through tripartite motif-containing 21 (TRIM21)
Donna L. Mallerya,1, William A. McEwana,1, Susanna R. Bidgooda,1, Greg J. Towersb, Chris M. Johnsona, and Leo C. Jamesa,2
aProtein and Nucleic Acid Chemistry Division, Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom; and
bDivision of Infection and Immunity, Medical Research Council Centre for Medical Molecular Virology, University College London, London W1T4JF, United Kingdom
Antibodies provide effective antiviral immunity despite the fact that viruses escape into cells when they infect. Here we show that antibodies remain attached to viruses after cell infection and mediate an intracellular immune response that disables virions in the cytosol. We have discovered that cells possess a cytosolic IgG receptor, tripartite motif-containing 21 (TRIM21), which binds to antibodies with a higher affinity than any other IgG receptor in the human body. TRIM21 rapidly recruits to incoming antibody-bound virus and targets it to the proteasome via its E3 ubiquitin ligase activity. Proteasomal targeting leads to rapid degradation of virions in the cytosol before translation of virally encoded genes. Infection experiments demonstrate that at physiological antibody concentrations TRIM21 neutralizes viral infection. These results reveal an intracellular arm of adaptive immunity in which the protection mediated by antibodies does not end at the cell membrane but continues inside the cell to provide a last line of defense against infection.
