25年來(lái),，科學(xué)家研發(fā)艾滋病疫苗的種種努力均以失敗告終,，現(xiàn)在,，他們決定另辟蹊徑——在一些“長(zhǎng)壽”的艾滋病患者身上尋找提供天然免疫力的抗體,。這些患者同艾滋病病毒（HIV）一起共存了20多年,，其間沒(méi)有出現(xiàn)任何發(fā)病跡象,。科學(xué)家認(rèn)為,，是天然免疫力讓這些病人躲過(guò)了HIV的攻擊,。有關(guān)研究發(fā)表在最新一期的《自然》雜志上。
美國(guó)紐約洛克菲勒大學(xué)的邁克爾?納森茲維革教授和同事對(duì)6名“長(zhǎng)壽”的艾滋病患者進(jìn)行了研究,。這些患者沒(méi)有服用抗病毒藥物,，也沒(méi)有顯現(xiàn)任何艾滋病跡象，比如,，飽受艾滋病病毒攻擊的某些白血球數(shù)量的下降,。科學(xué)家認(rèn)為,，這些人天生就攜帶有抵抗HIV的免疫系統(tǒng),，所以能做到“百毒不侵”。
科學(xué)家研究了這些病人血液內(nèi)發(fā)現(xiàn)的抵抗HIV的抗體,，結(jié)果顯示,，利用這些“長(zhǎng)壽”的艾滋病患者體內(nèi)產(chǎn)生的幾個(gè)抗體制造的一種疫苗能夠阻止HIV感染人體細(xì)胞。
納森茲維革說(shuō),，這些“長(zhǎng)壽”者的免疫系統(tǒng)能產(chǎn)生一套抗體，這些抗體能“同仇敵愾”地“抵消”艾滋病病毒,，阻止它感染免疫系統(tǒng)的血細(xì)胞,，使免疫系統(tǒng)能夠不斷自我復(fù)制。
納森茲維革說(shuō)：“病人體內(nèi)有不同的抗體,，每個(gè)抗體對(duì)HIV都有有限的抵消能力,，但如果它們結(jié)合在一起，就有可能威力無(wú)窮,。所以,，我們應(yīng)該復(fù)制天然的抗體。”
科學(xué)家將上述疫苗用于實(shí)驗(yàn)室試管中培育出來(lái)的人體細(xì)胞,，取得了成功,。科學(xué)家已經(jīng)鑒定出了這些“長(zhǎng)壽者”產(chǎn)生的500個(gè)抗體,，并且使用基因技術(shù)在實(shí)驗(yàn)室進(jìn)行了大規(guī)模的生產(chǎn),。科學(xué)家希望能在實(shí)驗(yàn)室動(dòng)物和志愿者身上進(jìn)行進(jìn)一步的測(cè)試,。
科學(xué)家都認(rèn)為,，疫苗是控制肆虐全球并每年殺死200萬(wàn)人的艾滋病的唯一有效的方式。過(guò)去幾十年中,，尋找艾滋病疫苗的研究遭遇了一系列挫折,。2007年,，美國(guó)制藥巨頭默克公司的研究被認(rèn)為最有可能研制出疫苗，有幾千個(gè)志愿者參與試驗(yàn),，但后來(lái)也因?yàn)閾?dān)心試驗(yàn)的疫苗可能實(shí)際上使參與者更容易受到感染而宣告失敗,。
許多人都會(huì)在感染艾滋病毒的幾年內(nèi)死去，有些人能應(yīng)付更長(zhǎng)時(shí)間,，也不必求助于藥物,，但很少有人（或許5000人中只有一個(gè)人）攜帶著艾滋病毒的天然免疫系統(tǒng)。
納森茲維革說(shuō),，新方法用自然的方式抵擋艾滋病病毒,，人體自身產(chǎn)生抗體，而不是使用傳統(tǒng)艾滋病疫苗使用的合成的“魔彈”抗體來(lái)刺激免疫力,，科學(xué)家已經(jīng)證明,，“魔彈”抗體并不成功。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature,，doi:10.1038/nature07930,，Johannes F. Scheid，Michel C. Nussenzweig
Broad diversity of neutralizing antibodies isolated from memory B cells in HIV-infected individuals
Johannes F. Scheid1,6, Hugo Mouquet1, Niklas Feldhahn1, Michael S. Seaman7, Klara Velinzon1, John Pietzsch1,8, Rene G. Ott2, Robert M. Anthony2, Henry Zebroski3, Arlene Hurley4, Adhuna Phogat9, Bimal Chakrabarti9, Yuxing Li9, Mark Connors10, Florencia Pereyra11, Bruce D. Walker11, Hedda Wardemann12, David Ho13, Richard T. Wyatt9, John R. Mascola9, Jeffrey V. Ravetch2 & Michel C. Nussenzweig1,5
1 Laboratory of Molecular Immunology,
2 Laboratory of Molecular Genetics and Immunology,
3 Proteomics Resource Center,
4 Rockefeller University Hospital, and,
5 Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
6 Charite Universitaetsmedizin, D-10117 Berlin, Germany
7 Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
8 Institute of Chemistry and Biochemistry, Freie Universit?t Berlin, D-14195 Berlin, Germany
9 Vaccine Research Center, and,
10 Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health Bethesda, Maryland 20892, USA
11 Partners AIDS Research Center, Mass General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
12 Max Planck Institute for Infection Biology, D-10117 Berlin, Germany
13 Aaron Diamond Aids Research Center; New York, New York 10065, USA
Antibodies to conserved epitopes on the human immunodeficiency virus (HIV) surface protein gp140 can protect against infection in non-human primates, and some infected individuals show high titres of broadly neutralizing immunoglobulin (Ig)G antibodies in their serum. However, little is known about the specificity and activity of these antibodies1, 2, 3. To characterize the memory antibody responses to HIV, we cloned 502 antibodies from HIV envelope-binding memory B cells from six HIV-infected patients with broadly neutralizing antibodies and low to intermediate viral loads. We show that in these patients, the B-cell memory response to gp140 is composed of up to 50 independent clones expressing high affinity neutralizing antibodies to the gp120 variable loops, the CD4-binding site, the co-receptor-binding site, and to a new neutralizing epitope that is in the same region of gp120 as the CD4-binding site. Thus, the IgG memory B-cell compartment in the selected group of patients with broad serum neutralizing activity to HIV is comprised of multiple clonal responses with neutralizing activity directed against several epitopes on gp120.
