據(jù)悉,英國(guó)加的夫大學(xué)的研究人員利用生物工程技術(shù)制造了強(qiáng)大免疫細(xì)胞,,其威力勝過(guò)我們體內(nèi)產(chǎn)生的常規(guī)“殺手”T細(xì)胞,可找尋和摧毀HIV,。這種超級(jí)殺手T細(xì)胞讓分子受體在實(shí)驗(yàn)室出現(xiàn)了進(jìn)化,,從而讓人體能抵抗導(dǎo)致我們免疫系統(tǒng)失敗的艾滋病毒(HIV)。
負(fù)責(zé)此項(xiàng)研究的加的夫大學(xué)的免疫學(xué)家安德魯·塞威爾說(shuō):“當(dāng)人體感染HIV時(shí),,人體免疫系統(tǒng)不知道此病毒將會(huì)干什么,,但我們知道。” HIV能扛過(guò)我們的免疫系統(tǒng),、藥物和疫苗對(duì)其打擊的原因之一是此病毒具有變色龍似的行為,,即其基因變異相當(dāng)容易,因此HIV能快速變換其外觀來(lái)逃避T細(xì)胞的攻擊,。但HIV的一些部件如此重要,,以至于其功能可以改變HIV病毒的結(jié)果。塞威爾小組針對(duì)此類蛋白的部件進(jìn)行了研究,。
HIV病毒通常將此蛋白隱藏于我們的免疫系統(tǒng)之下,,但當(dāng)HIV感染上正常細(xì)胞時(shí),此蛋白的小部件就會(huì)截留在所感染細(xì)胞的表面,,警告免疫系統(tǒng)這里潛伏有危險(xiǎn),。問(wèn)題是人體內(nèi)產(chǎn)生的殺手T細(xì)胞只做普普通通的工作,僅僅識(shí)別SL9,,塞威爾表示,。因此他的小組設(shè)計(jì)了超級(jí)T細(xì)胞,不僅能識(shí)別此蛋白名叫SL9的部件,,還能摧毀受感染的細(xì)胞,,從而防止HIV病毒的擴(kuò)散。
科學(xué)家從利用1996年收集到的具有獨(dú)特潛力的T細(xì)胞開始,,重新設(shè)計(jì)了能識(shí)別SL9的受體分子,,于是科學(xué)家選擇此變異受體來(lái)緊緊抓住SL9。在培養(yǎng)皿中,,這種定制的T細(xì)胞勝過(guò)正常的T細(xì)胞,,能輕易殺死感染HIV的細(xì)胞??茖W(xué)家發(fā)現(xiàn)此超級(jí)T細(xì)胞產(chǎn)生高濃度的化合物,,叫細(xì)胞因子(cytokines),這是成功免疫反應(yīng)的一種預(yù)示,。此超級(jí)T細(xì)胞還能識(shí)別SL9上的變異,,而正常T細(xì)胞常常被這種變異所迷惑。
該小組準(zhǔn)備測(cè)試基因改良的老鼠細(xì)胞,此老鼠細(xì)胞能產(chǎn)生人類免疫細(xì)胞,,也能感染HIV,。如果一切順利,他們希望再測(cè)試感染愛(ài)滋病病毒的人群,。但有些科學(xué)家擔(dān)心這種超級(jí)T細(xì)胞太強(qiáng)大,,可能存在副作用。此研究成果發(fā)表在最新出版的《自然—醫(yī)學(xué)》(Nature Medicine)雜志上,。(生物谷Bioon.com)
生物谷推薦原始出處:
Nature Medicine,,doi:10.1038/nm.1779,Andrew K Sewell,,James L Riley
Control of HIV-1 immune escape by CD8 T cells expressing enhanced T-cell receptor
Angel Varela-Rohena1, Peter E Molloy2, Steven M Dunn2, Yi Li2, Megan M Suhoski1, Richard G Carroll1, Anita Milicic3, Tara Mahon2, Deborah H Sutton2, Bruno Laugel3, Ruth Moysey2, Brian J Cameron2, Annelise Vuidepot2, Marco A Purbhoo2, David K Cole4, Rodney E Phillips3, Carl H June1, Bent K Jakobsen5, Andrew K Sewell3,4,6 & James L Riley1,6
HIV's considerable capacity to vary its HLA-I-restricted peptide antigens allows it to escape from host cytotoxic T lymphocytes (CTLs). Nevertheless, therapeutics able to target HLA-I-associated antigens, with specificity for the spectrum of preferred CTL escape mutants, could prove effective. Here we use phage display to isolate and enhance a T-cell antigen receptor (TCR) originating from a CTL line derived from an infected person and specific for the immunodominant HLA-A*02-restricted, HIVgag-specific peptide SLYNTVATL (SL9). High-affinity (KD < 400 pM) TCRs were produced that bound with a half-life in excess of 2.5 h, retained specificity, targeted HIV-infected cells and recognized all common escape variants of this epitope. CD8 T cells transduced with this supraphysiologic TCR produced a greater range of soluble factors and more interleukin-2 than those transduced with natural SL9-specific TCR, and they effectively controlled wild-type and mutant strains of HIV at effector-to-target ratios that could be achieved by T-cell therapy.