胰岛类器官研究进展

类器官是将具有多向分化潜能的干细胞或组织细胞在特定环境下培养分化成为能够模拟原生器官结构和功能的三维结构。类器官在各种疾病模型研究及药物筛选中发挥至关重要的作用。近年来,通过体外诱导胰腺组织或多能干细胞分化形成具有胰岛细胞功能的胰岛类器官研究成为热点,为胰岛相关疾病模型、药物研究以及糖尿病的治疗提供了新的手段。本文针对胰岛类器官的体外诱导方法及应用前景作一综述。     

人源肝脏类器官的研究及应用进展

肝脏是人体的主要代谢器官,在维持人体内环境稳态过程中起着关键调控作用。近年来,肝脏疾病严重威胁着人类健康,然而使用目前体外培养的细胞系和体内动物模型均无法深入揭示人肝脏疾病的发病机制,探索出有效潜在治疗靶点。人源肝脏类器官(human liver organoids, HLOs)是从人源细胞经体外3D分化培养得到的细胞团,能在体外模拟人肝脏的结构和功能,为人们理解肝脏生理结构、体外模拟肝脏疾病和开发治疗肝脏疾病药物提供了新模型。总结近年来具有代表性的HLOs模型的建立策略及应用,探讨目前HLOs模型存在的缺陷,以期为推动HLOs向临床应用提供参考。     

皮肤类器官的构建、功能及其应用研究进展

皮肤类器官作为一种新型的类器官模型,不仅能高度模拟皮肤组织的生理结构和功能,更好地在不同体外环境下还原较真实的皮肤生态,还可以应用于皮肤发育研究、皮肤疾病病理研究及药物筛选等领域。在干细胞研究中,皮肤类器官模型可以在特殊的生境下对具有特定功能的皮肤细胞及其附属物进行重建和改造,以弥补现有体外皮肤模型在结构、功能等方面的不足。基于此,皮肤类器官将会在皮肤再生、组织修复、药物筛选及医学美容等方面扮演越来越重要的角色。本文详述了皮肤类器官构建中所参与的细胞来源及近年来的应用,并对未来皮肤类器官的发展与优化做出了展望。     

心脏类器官

类器官是体外构建的一类由多种类型细胞组成的,与体内器官或组织高度相似的三维培养物,它能够模拟细胞所属器官的某些结构和生理功能。心血管疾病患病率及死亡率一直处于上升阶段,相关基础研究主要基于细胞和动物模型。心脏类器官是对传统心血管疾病模型的有效补充,在体外更真实和准确地反映人体心脏的生物学特性和功能,使其在疾病机制研究、药物开发、精准医疗和再生医学等领域具有广泛应用前景和独特优势。该文主要介绍了心脏类器官作为新一代疾病模型在心肌梗死、心力衰竭、遗传性心脏病和心律失常等方面的应用,并探讨了类器官技术未来的发展方向和面临的挑战。     

类器官的研究进展及应用

随着人类生物学研究的不断深入,需建立新的模型系统为研究提供了有力的工具。虽然传统的研究模型已被广泛应用,但难以准确反映组织、器官在机体中的生理现象。类器官 (Organoid) 是来源于干细胞或器官祖细胞的三维细胞聚集体,可分化和自组织形成具有人体相应器官的部分特定功能和结构。由于类器官具有人源性,可模拟器官发育和形成,在体外长期扩增中具有基因组稳定性,并能够形成活体生物库进行高通量筛选等优势,成为近年来备受关注的体外模型。目前,利用类器官模型结合新兴的基因编辑、器官芯片、单细胞RNA测序技术等,能够突破传统模型的瓶颈,在器官水平上为疾病模型的建立、药物研发、精准医疗以及再生医学等提供有价值的信息。文中就类器官分类及特性、研究应用、与其他技术结合应用及展望这4个方面进行综述。     

消化系统类器官研究进展

类器官是一种近年来新发展的细胞三维培养系统。类器官与真实器官的三维结构相似,并具有自我更新和再现组织来源等特点,从而能够更好地模拟真实器官的功能。类器官为研究器官发生、再生、疾病发病机制以及药物筛选提供了一个崭新的研究和应用平台。消化系统在人体内发挥着重要功能,目前已成功建立多种消化器官的类器官模型。本文就近年来味蕾、食管、胃、肝和小肠类器官的研究进展及相关应用进行综述,并对这几种类器官的应用前景进行展望。     

类器官及其应用的研究进展

类器官弥补了传统研究中细胞简单模型与动物复杂模型的不足,为生命体关键功能研究提供了重要实验基础,已成为当前研究热点,并在疾病机理研究、药物筛选、再生医学、生物材料评价等方面具有重大理论意义和应用前景.本文对近10年类器官研究进行了综述,阐述出类器官研究的发展历程和研究现状,重点综述了类器官的主要研究领域,并解析类器官研究中存在的关键科学问题,为类器官在生物医药、再生医学和疾病精准治疗领域的研究和应用提供新思路.     

多能干细胞诱导分化为肾脏类器官的研究进展与挑战

用于分化为多种类型细胞的多能干细胞(PSC)体外培养技术已被广泛应用于生物学领域中。由PSC分化而来的肾脏类器官可基本还原生物体内肾脏的组织结构和部分功能,在肾脏疾病模型研究和药物筛选中有重要作用,继续改善肾脏类器官的结构、功能和成熟度将会对肾脏再生治疗提供极大的帮助。研究肾脏类器官的重点在于体外准确模拟体内肾脏的发育过程。本文着重归纳了近十年来对胚胎肾发育过程研究的重点,对肾脏类器官分化技术的几个关键方案进行总结、分析和比较,并探讨肾脏类器官在分化研究和应用中将面临的挑战。     

骨类器官的构建及应用进展

骨骼疾病如骨质疏松、骨关节炎等已成为重要的人类健康问题,需要更深入地了解相关疾病的发病机制并开发更有效的治疗方法。由于2D细胞培养和动物实验等常规研究方法的局限性,近年来发展的类器官技术受到了极大关注。类器官作为干细胞衍生的自组织3D细胞簇,可以在体外更真实地模拟组织器官的复杂结构和生物功能。目前间充质干细胞、多能干细胞等衍生的骨类器官已逐步建立,不仅为疾病建模、药物筛选和生理病理基础研究提供了良好平台,还有望为骨缺损修复带来新希望。现对不同骨类器官模型的构建及主要应用进行概述,同时讨论了骨类器官培养面临的挑战,并对其未来发展进行展望,为构建结构功能更完善的骨类器官并将其应用于生物医学研究提供参考。     

肺成体干细胞体外培养模型的研究进展北大核心CSCD

目前,肺体外培养模型有肺类器官和肺芯片两种主要手段。肺类器官是离体的肺上皮干细胞在体外特定的三维培养环境中生长,自发形成具有自我更新能力的干细胞簇并成功分化出功能细胞。肺芯片是利用人工活性膜为细胞提供组织分层结构,模拟微环境和机械力的仿生微流体芯片。由于原有二维培养模式缺乏精确的微结构和功能,组织体外培养模型作为模拟肺部发育、稳态、损伤和再生机制的研究工具,为肺部纤维化、癌症等疾病的探索提供了新的手段和可能。本文就肺成体干细胞两种体外培养模型的分类、研发历史、建立方法、实际应用、优缺点等方面进行综述,期望为器官移植和再生、药物筛选等应用提供参考。     

类器官的应用研究进展

类器官是利用干细胞的自我更新和分化能力,在体外培养形成的一种微小组织器官类似物,在很大程度上具有体内相应器官的功能。迄今为止,在3D培养条件下,已经成功培养出多种类器官如肺、胃、肠、肝和肾等类器官。它们不仅可作为组织器官的替代品用于药物和临床研究,还可用于体内器官移植。本文综述了类器官在药物毒性检测、药效评价和新药筛选中的作用以及利用类器官建立疾病模型、研究组织器官发育和类器官在精准医疗、再生医学中的价值。     

Focus: Personalized Medicine: Value of Organoids from Comparative Epithelia Models

Organoids have tremendous therapeutic potential. They were recently defined as a collection of organ-specific cell types, which self-organize through cell-sorting, develop from stem cells, and perform an organ specific function. The ability to study organoid development and growth in culture and manipulate their genetic makeup makes them particularly suitable for studying development, disease, and drug efficacy. Organoids show great promise in personalized medicine. From a single patient biopsy, investigators can make hundreds of organoids with the genetic landscape of the patient of origin. This genetic similarity makes organoids an ideal system in which to test drug efficacy. While many investigators assume human organoids are the ultimate model system, we believe that the generation of epithelial organoids of comparative model organisms has great potential. Many key transport discoveries were made using marine organisms. In this paper, we describe how deriving organoids from the spiny dogfish shark, zebrafish, and killifish can contribute to the fields of comparative biology and disease modeling with future prospects for personalized medicine.     

Practical choice for robust and efficient differentiation of human pluripotent stem cells

Human pluripotent stem cells (hPSCs) have the distinct advantage of being able to differentiate into cells of all three germ layers. Target cells or tissues derived from hPSCs have many uses such as drug screening, disease modeling, and transplantation therapy. There are currently a wide variety of differentiation methods available. However, most of the existing differentiation methods are unreliable, with uneven differentiation efficiency and poor reproducibility. At the same time, it is difficult to choose the optimal method when faced with so many differentiation schemes, and it is time-consuming and costly to explore a new differentiation approach. Thus, it is critical to design a robust and efficient method of differentiation. In this review article, we summarize a comprehensive approach in which hPSCs are differentiated into target cells or organoids including brain, liver, blood, melanocytes, and mesenchymal cells. This was accomplished by employing an embryoid body-based three-dimensional (3D) suspension culture system with multiple cells co-cultured. The method has high stable differentiation efficiency compared to the conventional 2D culture and can meet the requirements of clinical application. Additionally, ex vivo co-culture models might be able to constitute organoids that are highly similar or mimic human organs for potential organ transplantation in the future.     

Liver diseases in the dish: iPSC and organoids as a new approach to modeling liver diseases

Liver diseases negatively impact the quality of life and survival of patients, and often require liver transplantation in cases that progress to organ failure. Understanding the cellular and molecular mechanisms of liver development and pathogenesis has been a challenging task, in part for the lack of adequate cellular models directly relevant to the human diseases.Recent technological advances in the stem cell field have shown the potentiality of induced pluripotent stem cells (iPSC) and liver organoids as the next generation tool to model in vitro liver diseases. Hepatocyte-like cells and cholangiocyte are currently being generated from skin fibroblasts and mononuclear blood cells reprogrammed into iPSC and have been successfully used for disease modeling, drug testing and gene editing, with the hope to be able to find application also in regenerative medicine. Protocols to generate other liver cell types are still under development, but the field is advancing rapidly. On the other end, liver cells can now be isolated from liver specimens (liver explants or liver biopsies) and cultured in specific conditions to form polarized 3D organoids. The purpose of this review is to summarize all these recent technological advances and their potential applications but also to analyze the current issues to be addressed before the technology can reach its full potential.     

The science and engineering of stem cell-derived organoids-examples from hepatic,biliary, and pancreatic tissues

The field of organoid engineering promises to revolutionize medicine with wide-ranging applications of scientific, engineering, and clinical interest, including precision and personalized medicine, gene editing, drug development, disease modelling, cellular therapy, and human development. Organoids are a three-dimensional (3D) miniature representation of a target organ, are initiated with stem/progenitor cells, and are extremely promising tools with which to model organ function. The biological basis for organoids is that they foster stem cell self-renewal, differentiation, and self-organization, recapitulating 3D tissue structure or function better than two-dimensional (2D) systems. In this review, we first discuss the importance of epithelial organs and the general properties of epithelial cells to provide a context and rationale for organoids of the liver, pancreas, and gall bladder. Next, we develop a general framework to understand self-organization, tissue hierarchy, and organoid cultivation. For each of these areas, we provide a historical context, and review a wide range of both biological and mathematical perspectives that enhance understanding of organoids. Next, we review existing techniques and progress in hepatobiliary and pancreatic organoid engineering. To do this, we review organoids from primary tissues, cell lines, and stem cells, and introduce engineering studies when applicable. We discuss non-invasive assessment of organoids, which can reveal the underlying biological mechanisms and enable improved assays for growth, metabolism, and function. Applications of organoids in cell therapy are also discussed. Taken together, we establish a broad scientific foundation for organoids and provide an in-depth review of hepatic, biliary and pancreatic organoids.     

Induced pluripotent stem cells for therapy personalization in pediatric patients:Focus on drug-induced adverse events

Adverse drug reactions(ADRs) are major clinical problems, particularly in special populations such as pediatric patients. Indeed, ADRs may be caused by a plethora of different drugs leading, in some cases, to hospitalization, disability or even death. In addition, pediatric patients may respond differently to drugs with respect to adults and may be prone to developing different kinds of ADRs,leading, in some cases, to more severe consequences. To improve the comprehension, and thus the prevention, of ADRs, the set-up of sensitive and personalized assays is urgently needed. Important progress is represented by the possibility of setting up groundbreaking patient-specific assays. This goal has been powerfully achieved using induced pluripotent stem cells(iPSCs). Due to their genetic and physiological species-specific differences and their ability to be differentiated ideally into all tissues of the human body, this model may be accurate in predicting drug toxicity, especially when this toxicity is related to individual genetic differences. This review is an up-to-date summary of the employment of iPSCs as a model to study ADRs, with particular attention to drugs used in the pediatric field. We especially focused on the intestinal, hepatic,pancreatic, renal, cardiac, and neuronal levels, also discussing progress in organoids creation. The latter are three-dimensional in vitro culture systems derived from pluripotent or adult stem cells simulating the architecture and functionality of native organs such as the intestine, liver, pancreas, kidney, heart,and brain. Based on the existing knowledge, these models are powerful and promising tools in multiple clinical applications including toxicity screening,disease modeling, personalized and regenerative medicine.     

类器官在乳腺癌相关研究中的应用进展

乳腺癌是女性最常见的癌症,目前乳腺癌的研究主要借助体内模型和传统细胞培养方法,然而研究表明,由于人类和动物之间固有的物种差异,以及器官和细胞之间组织结构的差异,使用上述两种研究方法研制出的药物,在临床试验中失败率高达90%,因此,类器官三维培养应运而生。类器官是一种具有空间结构的三维细胞复合体,它作为一种新的肿瘤研究模型,在精准医疗、器官移植、建立难治疾病模型、基因治疗和药物研发等方向具有广阔的应用前景,是未来生命科学研究的理想载体之一。乳腺癌作为一种表型复杂的异质性疾病,其患者生存率较低,而乳腺癌类器官可以重现人类乳腺癌的许多关键特征,故构建乳腺癌类器官生物库,将会为研究乳腺癌的发生、发展、转移和耐药机制提供一个新的平台。文中将系统介绍类器官的培养条件及其在乳腺癌相关研究中的应用,并对类器官的应用前景进行展望。     

胸腺类器官培养及应用进展

胸腺是人体重要的免疫器官,是T细胞分化成熟的场所,受损后容易引发自身免疫性疾病甚至恶性肿瘤。多年来,研究人员主要通过T细胞体外单层培养系统探索T细胞的发育过程,揭示胸腺损伤和再生的机制。但单层培养系统既不能重现胸腺独特的三维上皮性网状结构,也无法充分提供造血干细胞定向分化为T细胞所需的细胞因子和生长因子。胸腺类器官技术利用具有干细胞潜能的细胞,在体外通过三维培养模拟胸腺的解剖结构和胸腺上皮细胞介导的信号通路,与体内胸腺微环境十分接近。在研究T细胞分化和发育、胸腺相关疾病、重建机体免疫功能以及细胞治疗等方面,胸腺类器官呈现出巨大潜力。文中系统介绍了胸腺类器官的培养方法,比较了培养所用支架的优缺点;同时探讨了胸腺类器官在疾病建模、肿瘤靶向治疗、再生医学和器官移植等领域的应用,并对其前景进行展望。     

肠道类器官在肠疾病机制研究中的运用

肠道类器官由来自肠道的隐窝或干细胞在培养基质的三维（3D）支撑下构建形成,含有肠道的所有成熟细胞,已经成为研究肠道疾病机制全新且高效的平台。相较于二维（2D）细胞培养,肠道类器官不仅可以更加有效地模拟肠道的生理结构与功能,还可以在不同体外环境下更好地还原肠道的真实生态,因此在不同肠道疾病的发病机制研究中应用更为广泛。本文介绍了肠道类器官培养方式的新进展,综述了近年来肠道类器官在炎症性肠道疾病、结肠直肠癌和乳糜泻发病机制研究中的运用及进展,同时讨论了肠道类器官在药物研发与筛选方面的应用。