3D肝脏类器官 给肝病诊疗和医药科研带来无限遐想原创医生频道健康报医生频道11月8日肝脏类器官如果,3D打印的肝脏类器官可以批量生产并在体外大量存活,白蛋白、凝血因子等昂贵的生物制剂就可以让它们去制造了。如果,3D打印能够快速、完美复制肿瘤组织,药敏试验必然事半功倍,肿瘤精准治疗可能就不远了。这些设想都是由中国医学科学院北京协和医院肝胆外科毛一雷团队最新成果引发的。急性肝功能衰竭是由于各种因素引起的肝细胞大面积坏死或严重肝脏损伤,死亡率超过80%。肝移植是终末期肝病或急性肝衰竭病人唯一有效的治疗手段,但是由于供体缺乏、免疫排斥等因素限制了临床上的应用。因此寻找新的肝衰竭治疗方式,对于潜在的终末期肝病患者有着重要的意义。这是毛一雷教授和他的团队迈入3D打印的世界,制作肝脏类器官和肝癌活体模型的初衷。令人期盼的肝脏类器官肝细胞在体内有几乎无限的再生能力,当切除2/3健康的肝脏时,肝内剩余肝细胞会进行快速增殖,很快可以完全恢复至正常肝脏的体积和功能。如果在体外肝细胞依然具有这些特性,那么不仅有望解决肝移植的供体短缺问题,还会让肝病机制研究和药物研究发生翻天覆地的变化。但现实情况是,肝细胞一旦从身体中取出,仅能存活2~3天,而且其特有的复制功能也迅速消失。尽管人们通过加入各种生长因子延长了肝细胞的存活时间,但功能依然难以保持。随着细胞生物学领域的快速发展,近期有研究发现,三维培养体系能明显促进体外肝细胞的成熟功能,这提示三维培养环境提供给细胞的空间位置、压力信号和基质的黏附信息等,对肝细胞存活和发挥功能有重要作用。受此启发,毛一雷团队尝试用肝细胞作为“生物墨水”,借助3D生物打印技术制造肝脏类器官。毛一雷教授介绍,近年来3D生物打印技术在组织工程学中精确构建支架、细胞、组织以及器官方面展现出很大的潜力。国内外有不少团队都在尝试3D肝组织模型的构建,为的是应用在早期的药物研究以及疾病模型中,他们也是想要实现肝脏类器官构建的团队之一。类器官是指体外构建一个与体内结构和功能相似的组织体,由于可以产生与器官类似的生理作用、药物反应、疾病过程。因此,它被认为是疾病动物模型与人体器官结构和功能研究的桥梁。肝脏类器官活得很精彩尽管3D打印技术早已成熟,但肝脏生物3D打印却几乎没有经验可循。毛一雷团队首先探索了用于打印肝脏类器官的细胞、“墨水”以及诱导分化的条件。在实验中对比了原代肝细胞、胎肝细胞以及多种肝细胞系。综合考虑对3D打印的耐受性和肝功能之后,最终选择了一种人肝祖细胞进行3D生物打印。生物墨水也是反复测试后才最终敲定了5%明胶和1%海藻酸盐用作生物墨水组合。一系列的难点逐个破解后,团队利用3D生物打印技术,在明确细胞空间构型的情况下,进行干细胞定向分化研究,这有别于传统细胞研究中的平面培养和立体培养。结果显示,3D打印的肝脏类器官构成团簇,并具有了积累肝糖原、转运吲哚绿和乙酰化的低密度脂蛋白的能力。将这个肝脏类器官(他们自己命名的3DP-HO)移植到肝衰的小鼠体内后,小鼠寿命延长了数倍以上,体重减轻现象也显著下降。并且由于移植的肝脏类器官具有足量的肝细胞,所以移植后小鼠的血清肝功能指标显著改善,且具有人类肝细胞特有的异哇胍代谢功能。更令人振奋的是,小鼠肝脏在移植14天后自发构建出血管网络系统,毛一雷教授说:“这提示3D打印肝脏类器官在移植后的体内不仅能够‘干活’,还通过迅速搭建血管网络,做好了‘长期驻扎’的准备。相信随着技术的不断精进,我们距离生物打印完整功能器官又更近一步。今后,若这一技术能够顺利转化用于临床,有望为肝衰竭患者提供全新的治疗思路。”这一研究成果已于2020年5月20日在线发表在GUT杂志上。“复制”肿瘤为用药“指路”肝细胞癌是世界上最致命的肿瘤之一,但目前选择肝癌特异性药物缺乏明确依据,肿瘤位点检测又常因为其异质性受到影响,建立一个可靠的、可用的体外筛选模型至关重要,这也是该领域的绝对热点。既然肝脏类器官能够成功构建,肝细胞癌是不是也可以体外“复制”呢?毛一雷团队再一次使用了3D打印,并成功构建了肝细胞癌个性化模型,在对4种常用的肝癌靶向药物进行体外个体化筛选中,取得了精准的结果。研究近日发表在生物材料界排名第一的期刊Biomaterials上。文章被录用时,审稿人额外点评:所有以往的热门技术,成功率低且耗时长。毛等报道的方法达到了快速成瘤、高效的结果。这种方法显然要比目前的类器官等更有优点,该研究对于世界上该领域的各研究组都会有帮助或者促使他们思考转换方向。在这项研究中,毛一雷团队采用6名患者手术切除的HCC肿瘤样本用于模型构建,将患者原代HCC肿瘤细胞与明胶海藻酸钠生物墨水混合打印成型。3D打印构建体外模型简单高效,HCC细胞消化分离后2小时即可完成构建。相比之下,类器官和PDX模型的形成需要几个星期。并且,由于亲本肿瘤增殖能力有限,类器官产生成功率仅有26%,且形状、细胞数量、密度均不可控。使用患者原代肝细胞癌细胞构建的多个3D打印个体化HCC模型,在长期培养过程中生长良好。这些模型保留了肝癌的亲本特征,包括生物标志物、遗传改变和表达谱的稳定表达和维持。3D打印HCC模型在长期培养中十分可靠,在这6名患者的模型中测试了4种常用的经验性靶向药物,通过基因突变谱与药物靶标的对比测试,证实药物敏感性与突变靶标具有良好的一致性。毛一雷团队目前正把肿瘤的药敏研究拓展到结直肠癌肝转移、乳腺癌等肿瘤中,初步结果喜人。若能转化发展空间巨大提及上述两项研究的应用前景,毛一雷教授说:“我们还需要逐步完善这一系列研究,并努力推动它们向临床转化。目前看来,3D打印肝脏类器官还是很有发展前景的。肝脏具有众多内分泌功能,当我们能够在体外复制拥有同样功能的肝脏类器官时,或许就可以建造一个现代化的生物加工厂,让肝脏类器官为我们制造大量的各种凝血因子、白蛋白等生物制剂,拯救更多患者。肝细胞癌患者众多,如果用这一方法在药物检测方面为他们提供帮助,可以给临床治疗带来更加明确的指引。同时,我们或许也可以把这个方法扩展到更多其他实体肿瘤中,让肿瘤的精准治疗更早实现。” 毛一雷教授 文:健康报记者 郑颖璠制作:郑颖璠审核:方彤热文精选热点微创治疗胰腺癌如何让患者更获益?这些“功课”要做足热点查明!青岛此次疫情为患者共用CT室引发关注解读:为什么今年的诺贝尔奖生理学或医学奖颁给了他们?关注解读:她们凭借这把“剪刀”,斩获2020年诺贝尔化学奖热点从1.0到4.0,未来的互联网医院什么样?科普牙龈出血是预警?洗牙会让牙缝宽?智齿到底拔不拔?你关心的口腔问题一文全打尽
Comment on "Intraoperative Increase of Portal Venous Pressure is anImmediate Predictor of Posthepatectomy Liver Failure After MajorHepatectomy": A Prospective Study. Ann Surg. 2020 Mar 27. IF:10.13
Radiomics based on artificial intelligence in liver diseases: where weare? Gastroenterol Rep (Oxf). 2020 Apr 7;8(2):90-97. IF:2.96
Three-dimensional bioprinted hepatorganoids prolong survival of micewith liver failure. Gut. 2020 May 20:gutjnl-2019-319960. IF:19.819AbstractObjective:Shortage of organ donors, a critical challenge for treatment of end-stage organfailure, has motivated the development of alternative strategies to generateorgans in vitro. Here, we aim to describe the hepatorganoids, which is a livertissue model generated by three-dimensional (3D) bioprinting of HepaRG cellsand investigate its liver functions in vitro and in vivo.Design:3D bioprinted hepatorganoids (3DP-HOs) were constructed using HepaRG cells andbioink, according to specific 3D printing procedures. Liver functions of3DP-HOs were detected after 7 days of differentiation in vitro, which werelater transplanted into Fah-deficient mice. The in vivo liver functions of3DP-HOs were evaluated by survival time and liver damage of mice, human liverfunction markers and human-specific debrisoquine metabolite production.Results:3DP-HOs broadly acquired liver functions, such as ALBUMIN secretion, drugmetabolism and glycogen storage after 7 days of differentiation. Aftertransplantation into abdominal cavity of Fah-/-Rag2-/- mouse model of liverinjury, 3DP-HOs further matured and displayed increased synthesis ofliver-specific proteins. Particularly, the mice acquired human-specific drugmetabolism activities. Functional vascular systems were also formed intransplanted 3DP-HOs, further enhancing the material transport and liverfunctions of 3DP-HOs. Most importantly, transplantation of 3DP-HOssignificantly improved the survival of mice.Conclusions:Our results demonstrated a comprehensive proof of principle, which indicatedthat 3DP-HO model of liver tissues possessed in vivo hepatic functions andalleviated liver failure after transplantation, suggesting that 3D bioprintingcould be used to generate human liver tissues as the alternativetransplantation donors for treatment of liver diseases.
Recommendations formedical care of oncological patients during the COVID-19 epidemic: experiencesfrom China. Updates Surg. 2020 Jun;72(2):235-236. IF:2.587
Primary hepatic perivascular epithelioid cell neoplasm (PEComa) withfever in a 53-year-old man. Postgrad Med J. 2020 Aug;96(1138):505-506. IF:1.911
Response letter to: letter to the editor: three-dimensional bioprintedhepatorganoids in liver failure. Gut. 2020 Aug 14:gutjnl-2020-322471. IF:19.819
Liver injury in COVID-19: What do we know now? Hepatobiliary PancreatDis Int. 2020 Oct;19(5):407-408. IF:2.428
Liver stiffness: A novel predictor of postoperative complications inpatients with hepatocellular carcinoma. J Hepatol. 2020 Oct;73(4):987. IF:20.582
Identification ofRASSF1Apromoter hypermethylation as abiomarker for hepatocellular carcinoma.Cancer Cell Int20,547(2020). IF:4.175AbstractBackground:RAS association domain family protein 1A (RASSF1A) promoter hypermethylation issuggested to be linked to hepatocellular carcinoma (HCC), but the resultsremained controversial.Methods:We evaluated how RASSF1A promoter hypermethylation afects HCC risk and itsclinicopathological characteristics through meta-analysis. Data on DNAmethylation in HCC and relevant clinical data were also collected based on TheCancer Genome Atlas (TCGA) database to investigate the prognostic role ofRASSF1A promoter hypermethylation in HCC.Results:Forty-four articles involving 4777 individuals were enrolled in the pooledanalyses. The RASSF1A promoter methylation rate was notably higher in the HCCcases than the non-tumor cases and healthy individuals, and was signifcantlyrelated to hepatitis B virus (HBV) infection-positivity and large tumor size.Kaplan–Meier survival analysis revealed that HCC cases with RASSF1A promoterhypermethylation had worse outcomes. Receiver operating characteristic curvesconfrmed that RASSF1A promoter methylation may be a marker of HCC-relatedprognoses.Conclusions:RASSF1A promoter hypermethylation is a promising biomarker for the diagnosis ofHCC from tissue and peripheral blood, and is an emerging therapeutic targetagainst HCC.