韋余達(dá)，李爽，劉改改，張永賢，丁秋蓉

中國(guó)科學(xué)院上海生命科學(xué)研究院營(yíng)養(yǎng)科學(xué)研究所，上海 200031

基因組編輯技術(shù)在干細(xì)胞疾病模型建立和精準(zhǔn)醫(yī)療中的應(yīng)用

韋余達(dá)，李爽，劉改改，張永賢，丁秋蓉

中國(guó)科學(xué)院上海生命科學(xué)研究院營(yíng)養(yǎng)科學(xué)研究所，上海 200031

精準(zhǔn)醫(yī)療強(qiáng)調(diào)針對(duì)不同個(gè)體定制個(gè)性化治療方案，其推行需要精準(zhǔn)疾病模型的建立。人類(lèi)干細(xì)胞因其具有多能性而成為體外不同類(lèi)型的成體細(xì)胞和器官小體的潛在來(lái)源，其強(qiáng)增殖能力保證了充足原材料用于科研分析和大規(guī)模藥物篩選?；蚪M編輯技術(shù)(尤其是CRISPR/Cas9技術(shù))的快速發(fā)展使得在人多能干細(xì)胞和成體干細(xì)胞中進(jìn)行高效基因組編輯成為可能。兩者的有效結(jié)合能建立起針對(duì)不同遺傳致病背景的“個(gè)性化”疾病模型，有利于深入解析不同遺傳突變的致病機(jī)制和開(kāi)發(fā)高針對(duì)性的精準(zhǔn)醫(yī)療方案。本文對(duì)基因組編輯技術(shù)在人類(lèi)干細(xì)胞中的應(yīng)用以及利用干細(xì)胞疾病模型模擬罕見(jiàn)病和腫瘤發(fā)生的研究進(jìn)行了綜述。

CRISPR/Cas9技術(shù)；人多能干細(xì)胞；人成體干細(xì)胞；罕見(jiàn)病模型；腫瘤模型

2015年初隨著美國(guó)總統(tǒng)奧巴馬宣布開(kāi)展實(shí)施精準(zhǔn)醫(yī)療計(jì)劃(Precision medicine initiative)，精準(zhǔn)醫(yī)療立刻引起國(guó)內(nèi)外各界的高度關(guān)注，其基本概念是根據(jù)個(gè)體不同遺傳背景和健康狀態(tài)制定個(gè)體化的疾病預(yù)防和治療方案[1]。精準(zhǔn)醫(yī)療的實(shí)現(xiàn)需要大規(guī)?；蚪M測(cè)序支持，同時(shí)也需要有效的實(shí)驗(yàn)和藥物篩選平臺(tái)的建立，后者將有助于對(duì)遺傳測(cè)序數(shù)據(jù)的深入解析，和針對(duì)不同致病遺傳背景的個(gè)性化治療方案研發(fā)。

基因組編輯技術(shù)(Genome editing technology)結(jié)合人多能干細(xì)胞(Human pluripotent stem cells, hPSCs)以及成體干細(xì)胞生物學(xué)，提供了一個(gè)獨(dú)特的實(shí)驗(yàn)平臺(tái)體系，可用于建立“個(gè)性化”疾病模型供遺傳突變分析和大規(guī)模藥物篩選。目前，常用的基因組編輯技術(shù)主要包括鋅指核酸酶(Zinc finger nucleases, ZFNs)[2]、類(lèi)轉(zhuǎn)錄激活因子效應(yīng)物核酸酶(Transcription activator-like effector nucleases, TALENs)[3～7]和成簇規(guī)律間隔短回文重復(fù)序列系統(tǒng)(Clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins, CRISPR/Cas)[8～11](圖1)。相比ZFN和TALEN，CRISPR技術(shù)由于載體構(gòu)建簡(jiǎn)單、靶向位點(diǎn)選擇靈活、靶向效率更高，被廣泛用于各類(lèi)細(xì)胞和模式動(dòng)物的基因組編輯[12]。在模擬人類(lèi)疾病方面，人多能干細(xì)胞和成體干細(xì)胞由于自身干細(xì)胞特性具有一些明顯優(yōu)勢(shì)：(1)擁有人類(lèi)基因組，結(jié)合基因組編輯技術(shù)，可用于精確模擬人類(lèi)疾病遺傳背景；(2)具有多能性，在外界合適的誘導(dǎo)條件下，可以定向分化為各種體細(xì)胞類(lèi)型和類(lèi)器官小體(Organoids)，并且一定程度上體外分化過(guò)程能反應(yīng)體內(nèi)正常發(fā)育過(guò)程，可用于觀(guān)察疾病發(fā)生的中間狀態(tài)；(3)具有無(wú)限增殖和自我更新能力，同時(shí)區(qū)別于各種轉(zhuǎn)化細(xì)胞系，具有正常核型，提供了大量更符合生理狀態(tài)的細(xì)胞用于研究和藥物篩選?！皞€(gè)性化”疾病模型的建立有助于深入解析不同遺傳突變的致病機(jī)制和開(kāi)發(fā)高針對(duì)性的精準(zhǔn)醫(yī)療方案。本文對(duì)基因組編輯技術(shù)在人類(lèi)干細(xì)胞中的應(yīng)用以及利用干細(xì)胞疾病模型模擬罕見(jiàn)病和腫瘤發(fā)生的研究展開(kāi)綜述。

圖1 常用基因組編輯工具

1 干細(xì)胞基因組編輯

各種基因組編輯技術(shù)在人多能干細(xì)胞和成體干細(xì)胞中的應(yīng)用目前已經(jīng)比較成熟。基因組編輯技術(shù)可以在基因組特定位點(diǎn)進(jìn)行精確的靶向性剪切，形成DNA雙鏈缺口(DNA double-stranded breaks, DSBs)，細(xì)胞通過(guò)非同源性末端連接(Non-homologous end joining, NHEJ)或者同源重組(Homology-directed repair, HDR)對(duì)斷裂DNA進(jìn)行修復(fù)。利用這一生物過(guò)程，研究人員可以：(1)通過(guò)在基因編碼區(qū)引入移碼突變進(jìn)行靶向敲除基因；(2)通過(guò)外源模板(單鏈或者雙鏈DNA)定點(diǎn)敲入點(diǎn)突變、小肽段序列(如FLAG小肽)、以及基因編碼框(如熒光報(bào)告基因)；(3)通過(guò)同時(shí)靶向多個(gè)位點(diǎn)引入染色體結(jié)構(gòu)變異，包括染色體區(qū)域缺失(Deletion)、插入(Insertion)、重復(fù)(Duplication)、易位(Translocation)和倒位(Inversion)(圖2)[13～25]。

圖2 干細(xì)胞基因組編輯

相比ZFN和TALEN，CRISPR技術(shù)的靶向效率更高。Ding等[14]同時(shí)利用TALEN和CRISPR兩種基因編輯平臺(tái)，在相同的干細(xì)胞株中對(duì)相同/相近基因組位點(diǎn)進(jìn)行靶向，并對(duì)不同平臺(tái)的靶向活性進(jìn)行了橫向比較。CRISPR顯示出比TALEN更高更穩(wěn)定的活性，實(shí)驗(yàn)中所有 CRISPRs的靶向效率均大于50%。相比通過(guò)NHEJ過(guò)程引入移碼突變進(jìn)行基因敲除的效率，通過(guò)HDR重組敲入特定點(diǎn)突變或者特定序列的效率低很多?？紤]到細(xì)胞在DNA修復(fù)過(guò)程中NHEJ和HDR是兩個(gè)相互拮抗的過(guò)程，多個(gè)研究組通過(guò)體外篩選找到小分子化合物對(duì) NHEJ過(guò)程進(jìn)行抑制，從而達(dá)到了增強(qiáng)HDR過(guò)程而提高定點(diǎn)敲入效率的目的[26～28]。

脫靶率是基因靶向過(guò)程中受到廣泛關(guān)注的另外一個(gè)問(wèn)題。值得注意的是，脫靶率的高低不僅取決于不同的基因編輯平臺(tái)，也同樣受靶向序列、細(xì)胞類(lèi)型、基因編輯工具在細(xì)胞內(nèi)的表達(dá)時(shí)間和強(qiáng)度，以及脫靶率的檢測(cè)方法等影響。目前對(duì)于各種基因組編輯平臺(tái)脫靶率的比較還沒(méi)有確切的結(jié)論，而在各種轉(zhuǎn)化細(xì)胞系中對(duì)脫靶率的研究結(jié)果不能直接反應(yīng)正常細(xì)胞系(如hPSCs)中的脫靶情況。對(duì)CRISPR 和TALEN靶向后得到的若干單克隆干細(xì)胞株進(jìn)行的全基因組測(cè)序分析提示兩者在hPSCs中的脫靶率均很低[29～31]。由于受測(cè)序單克隆的數(shù)量限制，該結(jié)果不能全面反映脫靶情況，但提示脫靶現(xiàn)象是可以通過(guò)提高靶向序列的保守性、控制基因編輯蛋白表達(dá)強(qiáng)度和時(shí)間來(lái)避免。有意思的是，雖然沒(méi)有脫靶造成的非特異性突變，但相比干細(xì)胞母株，編輯后的單克隆(包括野生型和基因突變型)仍然被發(fā)現(xiàn)存在若干新的點(diǎn)突變。這些點(diǎn)突變附近序列和靶向序列沒(méi)有相似性，因此推測(cè)是在細(xì)胞培養(yǎng)和傳代中隨機(jī)發(fā)生，其中少數(shù)點(diǎn)突變被發(fā)現(xiàn)位于基因編碼區(qū)從而造成氨基酸突變[13,29～31]。這種隨機(jī)點(diǎn)突變的發(fā)生提示真正意義上的“isogenic”對(duì)照組是不存在的。為降低這種隨機(jī)突變對(duì)后期疾病表型檢測(cè)的影響，利用干細(xì)胞進(jìn)行體外疾病模擬時(shí)，需要多個(gè)野生型和突變型克隆同時(shí)比對(duì)，并利用多種對(duì)照組設(shè)計(jì)(如在基因敲除克隆中通過(guò)引入外源質(zhì)?；謴?fù)基因表達(dá)等)綜合分析致病遺傳因素對(duì)疾病的影響。

2 干細(xì)胞“個(gè)性化”疾病模型的建立

干細(xì)胞疾病模型的“個(gè)性化”主要表現(xiàn)在致病遺傳背景的“個(gè)性化”。同樣的疾病表型可以是多種不同的遺傳致病突變產(chǎn)生，而不同的致病突變由于其發(fā)病機(jī)理不盡相同而需要相應(yīng)的預(yù)防和治療方案，即所謂的“個(gè)性化”治療。干細(xì)胞疾病模型的建立可以通過(guò)兩種途徑：一種途徑是獲得患者的誘導(dǎo)性多能干細(xì)胞(Induced pluripotent stem cells, iPSCs)或者成體干細(xì)胞，體外直接分化培養(yǎng)后進(jìn)行疾病模擬。這種疾病模型的建立往往需要通過(guò)基因組編輯技術(shù)修復(fù)原細(xì)胞株中的致病突變獲得更為嚴(yán)格的野生型對(duì)照組細(xì)胞。另一種途徑是在野生型干細(xì)胞株中引入已知的致病突變進(jìn)行疾病模擬。后者可以跳過(guò)前者操作過(guò)程中可能需要的極其漫長(zhǎng)的患者篩選(尤其是罕見(jiàn)病患者)、體細(xì)胞重編程和iPSCs質(zhì)量檢測(cè)等過(guò)程，而可以直接通過(guò)基因組編輯技術(shù)快速引入致病突變，并且可以在同一株細(xì)胞中(即在同一個(gè)遺傳背景下)并行引入不同的致病突變，對(duì)不同致病突變導(dǎo)致的疾病表型進(jìn)行橫向比較。

2.1 罕見(jiàn)病疾病模型建立

罕見(jiàn)病是指那些發(fā)病率極低、多數(shù)由于特定基因缺陷導(dǎo)致的疾病，對(duì)它的研究屬于典型的精準(zhǔn)醫(yī)學(xué)研究范疇。針對(duì)罕見(jiàn)病的研究，將有助于提高人們對(duì)基礎(chǔ)疾病致病機(jī)理的認(rèn)識(shí)，發(fā)現(xiàn)新的治療方案。

目前，干細(xì)胞罕見(jiàn)病模型主要是模擬單基因突變疾病。建立成功的罕見(jiàn)病模型需要通過(guò)基因組編輯技術(shù)獲得嚴(yán)格的對(duì)照組，即對(duì)照組和實(shí)驗(yàn)組細(xì)胞株遺傳背景之間的差異只存在于致病基因的突變；隨后實(shí)驗(yàn)組和對(duì)照組細(xì)胞同時(shí)體外分化為疾病相關(guān)體細(xì)胞類(lèi)型，用于致病機(jī)理研究和藥物篩選(圖 3)。典型的例子包括：AKT2基因突變引起的肥胖低血糖代謝病癥模擬[13]；PLIN1基因突變引起的脂肪發(fā)育不良病癥模擬[13]；LMNA基因突變引起的早衰癥(Huntchinson-Gilford Progeria syndrome, HGPS)和維爾納綜合征(Atypical Werner syndrome, AWS)模擬[18]；A1AT基因突變引起的 alpha1-抗胰蛋白酶缺乏癥模擬[19]；LRRK2基因G2019S突變引起的帕金森病模擬[22]；SOD1基因突變引起的運(yùn)動(dòng)神經(jīng)元退化疾病模擬[32]等。Musunuru[33]在另一篇綜述中對(duì)上述疾病模型進(jìn)行了詳細(xì)討論。

圖3 干細(xì)胞罕見(jiàn)病模型

2.2 腫瘤疾病模型建立

腫瘤誘因往往是多種基因突變的同時(shí)發(fā)生，而不同類(lèi)型腫瘤，甚至不同個(gè)體的同類(lèi)型腫瘤，都具有自身的基因印記、腫瘤標(biāo)記物和基因突變類(lèi)型。針對(duì)特定的基因突變類(lèi)型設(shè)計(jì)相應(yīng)的治療方案在一些腫瘤治療中已經(jīng)取得顯著成效，如針對(duì) HER2突變的乳腺癌治療、針對(duì)EGFR突變的肺癌治療等?，F(xiàn)有的大規(guī)模癌癥基因組學(xué)數(shù)據(jù)為人們更全面分析腫瘤發(fā)生的遺傳因素提供了海量信息，而如何綜合解析這些信息，從中篩選出腫瘤發(fā)生的主要驅(qū)動(dòng)分子作為藥物靶點(diǎn)成為腫瘤精準(zhǔn)治療的關(guān)鍵。因此，建立和人體腫瘤發(fā)生高相似度、高特異性的體外腫瘤模型至關(guān)重要，一方面可以提供更直接準(zhǔn)確的平臺(tái)用于腫瘤發(fā)生機(jī)理研究和早期腫瘤診斷標(biāo)識(shí)物篩選；另一方面也可以提供更有效的體外細(xì)胞平臺(tái)用于抗癌藥物篩選。

圖4 干細(xì)胞腫瘤模型

在最近的多項(xiàng)研究中，干細(xì)胞疾病模型被用于模擬腫瘤發(fā)生(圖 4)。一種方案是利用病人來(lái)源的iPSCs對(duì)遺傳突變相對(duì)清晰的腫瘤或者腫瘤前期病癥進(jìn)行模擬。一項(xiàng)研究來(lái)自Kotini等[34]對(duì)骨髓增生異常綜合征(Myelodysplastic syndrome，MDS)的疾病模擬和解析[34]。MDS主要致病因素是發(fā)生在第7號(hào)染色體上20 Mb的染色體大片段缺失。他們從MDS病人中獲得突變的造血細(xì)胞，經(jīng)重編程得到攜帶片段缺失的MDS iPSCs；并且同時(shí)利用病人體內(nèi)依然存在的正常造血細(xì)胞獲得野生型 iPSCs對(duì)照組。相對(duì)正常iPSCs，突變型細(xì)胞在體外分化后表現(xiàn)出造血干細(xì)胞的分化功能異常。他們進(jìn)一步在野生型細(xì)胞株中引入相同的20 Mb染色體片段缺失，并觀(guān)察到類(lèi)似的疾病表型；隨后對(duì)缺失的20 Mb染色體片段中包含的多個(gè)基因進(jìn)行了表型回復(fù)篩選，找出了其中多個(gè)關(guān)鍵致病基因。這個(gè)研究充分展示了基于人多能干細(xì)胞的疾病模型在模擬疾病和探究疾病發(fā)病機(jī)制中的應(yīng)用價(jià)值。另一項(xiàng)工作來(lái)自 Lee等[35]對(duì)p53基因突變導(dǎo)致的李-佛美尼綜合癥(Li-Fraumeni syndrome，LFS)研究。他們將病人來(lái)源的 iPSCs以及相對(duì)應(yīng)的野生型對(duì)照組 iPSCs體外分化得到間充質(zhì)干細(xì)胞(Mesenchymal stem cells, MSCs)和成骨細(xì)胞(Osteoblasts, OBs)。對(duì)細(xì)胞進(jìn)行表達(dá)譜和功能分析后，他們發(fā)現(xiàn)LFS是由p53基因過(guò)度活化導(dǎo)致，并且p53的過(guò)度活化引起突變成骨細(xì)胞中H19印跡基因表達(dá)顯著下降，抑制干細(xì)胞向成骨細(xì)胞的分化。研究成果揭示了LFS的致病分子機(jī)制，并提示H19 和p53可以作為潛在藥物靶點(diǎn)。同時(shí)因?yàn)長(zhǎng)FS是骨肉瘤(Osteosarcoma，OS)發(fā)生的前期病癥，LFS iPSCs疾病模型可用于觀(guān)察在相對(duì)遺傳背景更復(fù)雜的骨肉瘤發(fā)生早期時(shí)的細(xì)胞內(nèi)變化，為尋找骨肉瘤的早期診斷標(biāo)志物和發(fā)生機(jī)制提供了一個(gè)獨(dú)特的細(xì)胞模型。

對(duì)遺傳突變背景復(fù)雜的腫瘤的體外模擬相對(duì)更具挑戰(zhàn)，尤其目前對(duì)大多數(shù)腫瘤的遺傳誘發(fā)因素研究仍處于探索階段。作為驗(yàn)證性實(shí)驗(yàn)，兩個(gè)研究組同時(shí)選擇了對(duì)誘發(fā)基因突變相對(duì)清晰的結(jié)直腸癌(Colorectal cancer, CRC)進(jìn)行模擬[36,37]。他們?cè)隗w外培養(yǎng)的人類(lèi)正常腸道成體干細(xì)胞中通過(guò) CRISPR/Cas技術(shù)陸續(xù)引入4個(gè)結(jié)腸癌基因突變(APC、P53、KRAS 和 SMAD4)后建立了結(jié)直腸癌類(lèi)器官模型。研究發(fā)現(xiàn)獲得四重突變的細(xì)胞能耐受抑癌藥物Nutlin-3，發(fā)生染色體數(shù)量異常，體外能不依賴(lài)于任何干細(xì)胞巢蛋白因子(Niche factor)生長(zhǎng)，并且在植入小鼠體內(nèi)后形成浸潤(rùn)性腫瘤，某種程度上反映了人類(lèi)結(jié)直腸癌的體內(nèi)發(fā)展。在另一個(gè)驗(yàn)證性實(shí)驗(yàn)中，Kim等[38]對(duì)從病人癌組織中獲得的原代胰腺導(dǎo)管癌細(xì)胞(Pancreatic ductaladenocarcinoma, PDAC)進(jìn)行重編程獲得PDAC iPSCs，同時(shí)利用癌旁組織細(xì)胞獲得野生型iPSC對(duì)照組。隨后他們將癌變和癌旁iPSCs注射入小鼠中形成畸胎瘤，在PDAC iPSCs形成的畸胎瘤中成功觀(guān)察到胰腺上皮內(nèi)瘤變(Pancreatic intraepithelial neoplasia, PanIN)等PDAC的癌前病變現(xiàn)象。另外，癌變的成體干細(xì)胞也可被直接用于腫瘤模型的建立。在最近的一項(xiàng)研究中，van de Wetering等[39]通過(guò)直接培養(yǎng)腫瘤病人的癌變腸道成體干細(xì)胞，體外誘導(dǎo)分化后獲得具有病人特定癌變遺傳背景的結(jié)直腸癌類(lèi)器官模型。初步的分析顯示病人來(lái)源的類(lèi)器官腫瘤模型能真實(shí)反應(yīng)患者體內(nèi)腫瘤的多個(gè)重要特征，而這些具有病人“個(gè)性化”遺傳背景的類(lèi)器官模型可以被直接用于基因突變研究和針對(duì)性的藥物篩選。隨著體外類(lèi)器官培養(yǎng)技術(shù)的進(jìn)步，這樣的腫瘤模型將會(huì)廣泛的應(yīng)用到對(duì)更多腫瘤類(lèi)型的研究中。

2.3 目前存在的問(wèn)題

干細(xì)胞疾病模擬體系目前存在的問(wèn)題主要體現(xiàn)在各種現(xiàn)有的體細(xì)胞分化平臺(tái)不夠成熟和穩(wěn)定[40～42]體外分化得到的體細(xì)胞一方面大都處于發(fā)育過(guò)程中的前體細(xì)胞階段，不能完全反應(yīng)體內(nèi)細(xì)胞的生理狀態(tài)；另一方面不是均一的細(xì)胞群體。在嚴(yán)格細(xì)胞對(duì)照組之間，甚至同一株干細(xì)胞株在不同批次、不同操作者處理之間，分化得到的細(xì)胞群體都存在較大差異，因此給疾病表型的觀(guān)察和實(shí)驗(yàn)重復(fù)帶來(lái)困難。因而實(shí)驗(yàn)設(shè)計(jì)時(shí)需要考慮多種對(duì)照組設(shè)計(jì)，并且盡可能通過(guò)細(xì)胞分子標(biāo)識(shí)物分選等方式篩選出相對(duì)單一類(lèi)型的細(xì)胞群體進(jìn)行研究，控制體外分化帶來(lái)的系統(tǒng)誤差對(duì)實(shí)驗(yàn)結(jié)果的影響。

干細(xì)胞疾病模擬系統(tǒng)存在的另一個(gè)局限性在于目前的體細(xì)胞分化只能覆蓋一小部分細(xì)胞類(lèi)型，體外培養(yǎng)方式也大都是單個(gè)細(xì)胞類(lèi)型的2D培養(yǎng)?？紤]到疾病的發(fā)生涉及多個(gè)細(xì)胞類(lèi)型、多個(gè)組織器官的交互影響，現(xiàn)有的干細(xì)胞疾病模擬平臺(tái)需要向3D培養(yǎng)、多細(xì)胞、多組織器官等更符合生理狀態(tài)的方向發(fā)展。

值得慶幸的是，目前多能干細(xì)胞或者成體干細(xì)胞在體外進(jìn)行類(lèi)器官小體培養(yǎng)的體系發(fā)展迅速。在體外3D培養(yǎng)條件下，通過(guò)合適生長(zhǎng)因子誘導(dǎo)后，細(xì)胞可以通過(guò)自組織(self-organization)的方式形成多種器官小體，如腸小體[43]，視杯結(jié)構(gòu)[44]，肝臟小體[45]，腦小體[46]，腎臟小體[47,48]和胃小體[49]等。這樣的器官小體培養(yǎng)體系會(huì)日益成熟，而更多的成體細(xì)胞分化平臺(tái)也會(huì)被研發(fā)建立，相信未來(lái)干細(xì)胞疾病模擬系統(tǒng)將能從器官水平更真實(shí)的模擬人體疾病發(fā)生。

3 展 望

精確疾病模型的建立在疾病機(jī)理探究和新的治療方案開(kāi)發(fā)過(guò)程中至關(guān)重要?；蚪M編輯技術(shù)和多能干細(xì)胞結(jié)合建立的干細(xì)胞疾病模型，為疾病研究提供了一個(gè)全新的研究平臺(tái)，能在人的特定遺傳背景下(相對(duì)小鼠等其他模式生物)，在更切合生理狀態(tài)的正常細(xì)胞體系中(相對(duì)其他各種轉(zhuǎn)化細(xì)胞系)，更加精確的再現(xiàn)人類(lèi)疾病的發(fā)生過(guò)程。隨著各種干細(xì)胞體外分化平臺(tái)的建立和成熟，體外培養(yǎng)體系的優(yōu)化，基因組編輯技術(shù)的進(jìn)一步發(fā)展，針對(duì)不同遺傳致病背景的干細(xì)胞“個(gè)性化”疾病模型將為精準(zhǔn)醫(yī)療提供獨(dú)特的研發(fā)平臺(tái)，助力于新的更具針對(duì)性的藥物開(kāi)發(fā)。

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(責(zé)任編委: 王曉群)

Use of genome editing tools in human stem cell-based disease modeling and precision medicine

Yuda Wei, Shuang Li, Gaigai Liu, Yongxian Zhang, Qiurong Ding
Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Shanghai 200031, China

Precision medicine emerges as a new approach that takes into account individual variability. The successful conduct of precision medicine requires the use of precise disease models. Human pluripotent stem cells (hPSCs), as well as adult stem cells, can be differentiated into a variety of human somatic cell types that can be used for research and drug screening. The development of genome editing technology over the past few years, especially the CRISPR/Cas system, has made it feasible to precisely and efficiently edit the genetic background. Therefore, disease modeling by using a combination of human stem cells and genome editing technology has offered a new platform to generate “ personalized ” disease models, which allow the study of the contribution of individual genetic variabilities to disease progression and the development of precise treatments. In this review, recent advances in the use of genome editing in human stem cells and the generation of stem cell models for rare diseases and cancers are discussed.

CRISPR/Cas9; human pluripotent stem cells; adult stem cells; rare disease modeling; cancer modeling

2015-05-29;

2015-07-01

上海市浦江人才計(jì)劃(編號(hào)：15PJ1409200)資助

韋余達(dá)，碩士研究生，專(zhuān)業(yè)方向：干細(xì)胞腫瘤疾病模型。E-mail: ydwei@sibs.ac.cn

丁秋蓉，博士，研究員，研究方向：干細(xì)胞與轉(zhuǎn)化醫(yī)學(xué)。E-mail: qrding@sibs.ac.cn

10.16288/j.yczz.15-239

時(shí)間:2015-7-2 15:28:35

URL:http://www.cnki.net/kcms/detail/11.1913.R.20150702.1528.001.html