Mechanism of Reversal of Precancerous Lesions of Gastric Cancer by Celastrus orbiculatus Extract via Regulating Lgr5/Wnt/β-catenin Signaling Pathway / 中国实验方剂学杂志

ObjectiveThis study aims to investigate the mechanism in which Celastrus orbiculatus extract （COE） affects the proliferation and differentiation of gastric organoids and the expression of Lgr5 and thus reverses the precancerous lesions of gastric cancer （PLGC） by regulating the leucine-rich repeat containing G protein-coupled receptor 5 （Lgr5）/Wingless （Wnt）/β-catenin signaling pathway based on a gastric organoid injury model. MethodGastric organoids were established based on stem cells of the mouse gastric gland. Gastric organoid injury models were constructed by treating gastric organoids with N-methyl-N'-nitro-N-nitrosoguanidine （MNNG， 0.02 mg·L-1）. Gastric organoid injury models were randomly divided into normal group， model group （0.02 mg·L-1 MNNG）， low， medium， and high dose （5， 10， 20 mg·L-1） groups of COE， and Wnt inhibitor Dickkopf-related protein 1 （DKK1） （0.5 mg·L-1） group， and they were treated with respective agents for 24 h. The number and volume of gastric organoids under different drug concentrations were observed under a microscope. The viability of the gastric organoid injury models was detected by Methyl thiazolyl tetrazolium （MTT） assay. The morphology and pathology of gastric organoids were observed using Hematoxylin and Eosin （HE） staining. The expression levels of Lgr5， Mucin2 （MUC2）， Mucin5AC （MUC5AC）， Mucin6 （MUC6）， Wnt， and β-catenin in gastric organoids under different drug concentrations were detected by Western blot （WB）. ResultCompared with the normal group， the number， volume， and activity of gastric organoids in the model group were decreased （P<0.01）， while the expressions of Lgr5， MUC2， Wnt， and β-catenin were significantly increased （P<0.01）. The expressions of MUC5AC and MUC6 were significantly decreased （P<0.01）. Compared with the model group， the number and volume of gastric organoids in the low， medium， and high dose groups of COE were all improved （P<0.01）， and the vitality of gastric organoids was significantly enhanced （P<0.01）. The effect was the most significant at a COE concentration of 20 mg·L-1 （P<0.01）. The expressions of Lgr5 and MUC2 in the medium and high dose groups of COE were significantly reduced （P<0.01）， while the expression of MUC5AC and MUC6 were significantly increased in the low， medium， and high dose groups of COE （P<0.05， P<0.01）. Compared with the model group， Wnt inhibitors could promote the expression of MUC5AC and MUC6 in gastric organoids （P<0.05， P<0.01） and reduce the expression of MUC2， Wnt， and β-catenin. In addition， the combined use of COE at high concentrations and Wnt inhibitors could further promote this trend （P<0.01）. ConclusionCOE inhibits the Wnt/β-catenin pathway by inhibiting the expression of Lgr5， MUC2， Wnt， and β-catenin and promoting the expression of MUC5AC and MUC6， thus promoting the proliferation and differentiation of gastric organoids and reversing the PLGC process.

Advances in high-throughput automated organoid-on-a-chip system / 天津医药

Organoids are in vitro three-dimensional(3D)multicellular cultures that are generated through deploying the self-renewal and self-organizing capacities of stem cells.They recapitulate key structural and functional features of corresponding organs or tissues,providing an ideal in vitro model and research platform for the study of developmental biology,regenerative medicine,disease modeling and drug development.The conventional organoid culture system mainly relies on manual operations with lengthy and complicated procedures,which generate organoid cultures of individual variations and batch differences,limiting their translational applications.Therefore,to engineer the organoid culture system by introducing microfluidic chip technology to enhance the throughput and automation level,is of great significance for achieving large-scale,homogeneous,and standardized organoid cultures.This article reviews the current research progress of high-throughput and automated organoid chips and discusses the main limitations and potential challenges for the future study.

Construction of airway organoid microinjection and polarity reversal model / 天津医药

Objective To explore novel methods for efficient respiratory viral infection of organoids by microinjection and polarity inversion techniques.Methods Lung tissue samples were obtained from 8-week-old male C57BL/6 mouse,and respiratory epithelial cells were extracted to establish a transwell organoid culture model.The green fluorescent protein(GFP)labeled influenza virus PR8(GFP-PR8)was quantitatively injected into organoids by improving the traditional microinjection platform,and morphologic changes in organoids and the immunofluorescence staining characteristics of tight junction proteins and microtubule proteins were observed.Polarity inversion apical-out(AO)was induced by suspension culture,and the morphological characteristics of polarity inversion was determined by HE staining.Normal and inverted organoids were infected with PR8,and the infection efficiency and expression differences of key pathway genes under different virus concentrations were observed.Results Ordinary organoids showed a significant increase in volume after microinjection.Following PR8 injection,the efficiency of infection was significantly higher in the apical region of organoids,accompanied by noticeable damage,as evidenced by significant down-regulation of tight junction proteins and microtubule protein expression.After suspension culture of the organoids,the polarity of ciliated cells gradually inverted outward over time,and the proportion of AO organoids stabilized on the 6th day.The efficiency of viral infection significantly increased in the inverted organoids,accompanied by significant cellular damage.After PR8 infection at 0.01 MOI,AO organoids showed significant changes in the inflammatory pathway and differentiation-related genes,with the opposite trend observed after higher concentration of PR8 infection.Conclusion Both polarity inversion and microinjection techniques significantly enhance the efficiency of influenza virus infection in organoids,thereby facilitating organoid widespread application in the field of respiratory tract infections.

Study of Lkb1 regulates epithelial regeneration in asthma using airway organoid / 天津医药

Objective To explore the mechanism of Lkb1 regulated epithelial regeneration in asthma by airway organoid culture.Methods Lkb1f/f(the control group,n=10)and Scgb1a1CreER;Lkb1f/fmice(the Lkb1 knockout group,n=9)were taken to establish allergic asthma models by aerosol inhalation of ovalbumin(OVA).Bronchial lavage fluid(BALF)and lung tissue were collected.The number of inflammatory cells in BALF were counted.The amount of CLCA3 positive cells was compared by immunofluorescence staining of lung tissue sections.Club cells were selected by flow cytometry for organoid culture.The average diameter of organoids and organoid formation rate were calculated.Expression levels of goblet cell marker CLCA3,cilia cell markers FOXJ1 and AMPK in Club cells were detected by RT-PCR.Results There were no significant differences in the number of macrophages,eosinophils,neutrophils and lymphocytes in BALF between the control group and the Lkb1 knockout group.The number of CLCA3 positive cells were decreased after Lkb1 knockout.Results of organoid culture showed that the average diameter of organoids derived from Club cells and organoid formation rate were decreased after the absence of Lkb1.The expression of FOXJ1 was reduced.After Lkb1 deletion,the expression of AMPKα in Club cells were decreased and the proliferation of Club cells was inhibited.Activation of AMPK,the downstream signaling pathway of Lkb1,could attenuate the effect of Lkb1 deficiency on the regeneration of Club cells.Conclusion Lkb1 promotes the proliferation of airway progenitor cells by AMPK pathway.

Research progress of cerebral organoid technology and its application in stroke treatment / 天津医药

Cerebral organoids are three-dimensional nerve cultures induced by embryonic stem cells(ESCs)or induced pluripotent stem cells(iPSCs)that mimic the structure and function of human brain.With the continuous optimization of cerebral organoid culture technology and the combination with emerging technologies such as organ transplantation,gene editing and organoids-on-chip,complex brain tissue structures such as functional vascular structures and neural circuits have been produced,which provides new methods and ideas for studying human brain development and diseases.This article reviews the latest advances in brain organoid technology,describes its application in neurological diseases and advances in stroke modeling and transplantation treatment.

Bibliometric analysis of researches on liver organoids / 中国组织工程研究

BACKGROUND:In recent years,the development of liver organoids has made it a hot spot in the field of international liver disease research,but there is still no article on the bibliometric analysis of liver organoids. OBJECTIVE:To explore the hot trends in liver organoids in the last 20 years based on bibliometrics and visualization analysis. METHODS:We searched the articles about liver organoids in the Web of Science Core Collection from January 1,2002 to November 12,2022.Origin,Office,and CiteSpace software were used for bibliometrics and visualization analysis.We statistically analyzed the number of annually published articles,countries,institutions,authors,journals,and keywords of the articles by generating charts. RESULTS AND CONCLUSION:The number of articles,citation frequency,institutions and personnel involved in the research about liver organoids showed an overall upward trend in the last 20 years,indicating that the field was growing rapidly and attention was increasing.The USA had published the most papers and had the strongest influence in this field.Although it had invested a lot of time and energy,the number of papers published by a single research institution in the USA was not the highest among many research institutions.China was second only to the USA in the number of publications,with the Chinese Academy of Sciences and Fudan University leading the list.Utrecht University in the Netherlands was the institution with the most publications.Clevers H was the author with the highest number of articles.The article with the highest co-citation frequency was"Long-term culture of genome-stable bipotent stem cells from adult human liver".The main fields of study for liver organoids were Molecular Science,Biology,and Immunology.The most frequently occurring keywords were stem cell,in vitro,and culture.The research hotspots in the liver organoids field were mainly focused on in vitro stem cell three-dimensional culture,differentiation and gene expression.

Effect of cell mechanics on morphogenesis of MDCK lobular organoid / 中国组织工程研究

BACKGROUND:The development of tissues and organs in the body is a precise and autonomously regulated process,and the function of biomechanical factors at this macroscale is a basic scientific question worth exploring. OBJECTIVE:To investigate the roles of cell mechanics in morphogenesis of the lobular organoid of 3D Madin-Darby canine kidney(MDCK). METHODS:The formation of MDCK lobular organoid was visualized by fluorescence resonance energy transfer technology,and the influence of different cellular mechanical signals and extracellular matrix environment on lobular organoid formation and corresponding changes in extracellular regulated protein kinases(ERK)activity were examined. RESULTS AND CONCLUSION:(1)Inhibition of ERK signaling pathway can inhibit the growth of MDCK lobular organoid.(2)Inhibition of cell contractile force signals such as ROCK pathway and Myosin Ⅱ activity,reduced ERK activity and lobular organoid size.(3)Selective inhibition of calcium channels in plasma membrane and endoplasmic reticulum led to reduced ERK activity and lobular organoid growth.(4)By inhibiting the mechanically-sensitive receptor Piezo ion channel or integrin signal on the cell membrane,the lobular organoid became smaller or MDCK cells could not generate tissue morphology.(5)Extracellular matrix compositions affected the morphogenesis of lobular organoid.The addition of type I collagen in Matrigel changed the lobular organoid to elongated shape.(6)The results of this study preliminarily show that mechanical signals in the cells and extracellular matrix environment play an important role in culturing MDCK lobular organoid,and provides certain molecular mechanisms.

Mechanism of Qingre Huayu Jianpi Prescription Inhibiting Development of Colitis-associated Colorectal Cancer in Mice / 中国实验方剂学杂志

ObjectiveTo explore the effect of Qingre Huayu Jianpi prescription （QHJ） on colitis-associated colorectal cancer （CAC） in mice， and its related mechanism. MethodC57BL/6 mice were randomly divided into four groups including the normal， model， QHJ low-dose （QHJ-L， 10 g·kg-1）， and QHJ high-dose （QHJ-H， 40 g·kg-1） groups. Azoxymethane （AOM） and dextran sodium sulfate （DSS） were combined to chemically build a CAC mouse model for 14 weeks. Each drug group was given intragastrically from the 5th week to the 14th week， once per day. An equal volume of water was fed to the normal and model groups. The mouse survival rate， colon length， weight， and pathological alterations were assessed. The protein expressions of Wnt-3a protein signaling （Wnt3a）， β-catenin， Non-phosphor-β-catenin （Non-p-β-catenin）， and cholesterol-binding glycoproteins 133 （CD133） were detected by Western blot. The localization and expression of the cluster of differentiation （CD） 80 and CD11 antigen-like family member B （CD11b） were detected by immunohistochemistry （IHC）. The colon organoids derived from CAC mice were isolated and cultured to detect the expression of Wnt signaling pathway-related proteins. ResultThe survival rate of the CAC mice was improved by QHJ treatment and the number of colon tumors was inhibited significantly. Compared with those in the normal group， the expression levels of Wnt3a， β-catenin， Non-p-β-catenin， and CD133 in colon tissues in the model group were significantly increased （P<0.05， P<0.01）. Compared with those in the model group， the levels of Wnt3a and β-catenin in the QHJ-L group were significantly decreased （P<0.01）， and the protein levels of Wnt3a， β-catenin， Non-p-β-catenin， and CD133 in the QHJ-H group were significantly decreased （P<0.05， P<0.01）. Meanwhile， the expression level of CD11b in the model group was significantly increased compared with that in the normal group while the CD80 level was significantly decreased （P<0.05， P<0.01）. Compared with those in the model group， CD11b in QHJ-L and QHJ-H groups was significantly decreased， and CD80 was significantly increased（P<0.05， P<0.01）. The expressions of Non-p-β-catenin and CD133 in colonic organoids of CAC model mice were significantly increased， while QHJ treatment could inhibit the expressions of Non-p-β-catenin and CD133 in colonic organoids （P<0.01）. ConclusionQHJ could inhibit the inflammation-cancer development in CAC mice， the mechanism of which might be related to regulating the microenvironment and inhibiting the over-activation of Wnt signaling.

Application of brain organoids in environmental toxicology / 环境与职业医学

Since the 19th century, the emergence of model systems has helped researchers further understand cellular signaling pathways, identify potential drug targets, and conduct environmental toxicological studies. Exogenous chemicals, such as pollutants, drugs, and industrial chemicals, may affect brain biological processes and functions and eventually lead to neurological diseases. However, the brain is a complex and well-organized human organ, which is fundamentally different from any existing model system. Animal models may not be able to completely simulate the human brain in testing the neurotoxicity of environmental pollutants due to species differences. Human brain organoids, generated from human pluripotent stem cells, are emerging model systems for neurotoxicological research in line with the real situation of human body at the level of genome, transcriptome, and metabolome, and provide an effective platform for testing neurotoxicity of environmental toxins. We reviewed the latest development of brain organoids technology and its application in the evaluation of environmental neurotoxins, and provided new insights into the application of brain organoids in environmental neurotoxicology.

Advances in research on the application of organoids in radiotherapy / 中华放射医学与防护杂志

With the extensive applications of nuclear energy in the military, scientific research, and medical fields, radiological medicine has developed into a significant discipline. So far, studies of radiology have been conducted mostly using cell and animal models, both of which have limitations. Organoids, as 3D in vitro culture systems derived from tissue stem cells, have filled the gap left by these conventional models. They have been widely applied in review, disease research, drug development, and cancer modeling since their structures, functions, and genetic characteristics are akin to those of primary tissues. This review presents the applications of organoid models of various organ types in radiotherapy, as well as the limitations and prospects of organoids.

Advances in research of heart organoid and its application in drug discovery / 药学学报

Cardiovascular diseases are fatal threats to human health and also important fields in drug discovery. Organoid is a miniature with the structure and function similar to the organ, which is formed by the self-updating and specific differentiation of stem cells during the in vitro culture. Considering its characteristics of human origin, physical features, self-assembling and genetic stability, heart organoid has attracted much attention in the study of cardiogenesis, cardiovascular diseases modeling and related drug research. Hence, this article will review the development of heart organoids and its construction strategies, highlighting its application and prospects in drug discovery.

Advances in organoids of the digestive system / 生物工程学报

Organoid is a newly developed cellular there-dimensional culture system in recent years. Organoids have a three-dimensional structure, which is similar to that of the real organs. Together with the characteristics of self-renewal and reproduction of tissue origin, organoids can better simulate the function of real organs. Organoids provide a new platform for the study of organogenesis, regeneration, disease pathogenesis, and drug screening. The digestive system is an essential part of the human body and performs important functions. To date, organoid models of various digestive organs have been successfully established. This review summarizes the latest research progress of organoids of taste buds, esophagi, stomachs, livers and intestines, and prospects future application of organoids.

Development of an olfactory epithelial organoid culture system based on small molecule screening / 生物工程学报

Olfactory epithelium, which detects and transmits odor signals, is critical for the function of olfactory system. Olfactory epithelium is able to recover spontaneously after injury under normal circumstances, but this ability is dampened in certain diseases or senility, which causes olfactory dysfunction. The olfactory epithelium consists of basal cells, sustentacular cells and olfactory sensory neurons. In order to develop an olfactory epithelial organoid containing multiple olfactory cell types in vitro, we used three-dimensional culture model and small molecules screening. This organoid system consists of horizontal basal-like cells, globose basal-like cells, sustentacular-like cells and olfactory sensory neurons-like cells. Through statistical analysis of clone diameter, immunofluorescence staining and qPCR detection of the expression level of related marker genes. We identified a series of growth factors and small molecule compounds that affected the proliferation, composition and gene expression of the organoids. CHIR-99021, an activator of Wnt signaling pathway, increased the colony formation and proliferation rate of olfactory epithelial organoids and the expression level of marker genes of olfactory sensory neurons-like cells. In addition, each factor in the culture system increased the proportion of c-Kit-positive globose basal-like cell colonies in organoids. Moreover, EGF and vitamin C were both beneficial to the expression of horizontal basal-like cell marker genes in organoids. The established olfactory epithelial organoid system mimicked the process of olfactory epithelial stem cells differentiating into various olfactory epithelial cell types, thus providing a research model for studying olfactory epithelial tissue regeneration, the pathological mechanism of olfactory dysfunction and drug screening for olfactory dysfunction treatment.

Establishment and Evaluation of Intestinal Injury Model of Mouse Acute Graft Versus Host Disease Based on An Organoid Technology / 中国实验血液学杂志

OBJECTIVE@#To establish an intestinal organoid model that mimic acute graft versus host disease (aGVHD) caused intestinal injuries by using aGVHD murine model serum and organoid culture system, and explore the changes of aGVHD intestine in vitro by advantage of organoid technology.@*METHODS@#20-22 g female C57BL/6 mice and 20-22 g female BALB/c mice were used as donors and recipients for bone marrow transplantation, respectively. Within 4-6 h after receiving a lethal dose (8.0 Gy) of γ ray total body irradiation, a total of 0.25 ml of murine derived bone marrow cells (1×107/mice, n=20) and spleen nucleated cells (5×106/mice, n=20) was infused to establish a mouse model of aGVHD (n=20). The aGVHD mice were anesthetized at the 7th day after transplantation, and the veinal blood was harvested by removing the eyeballs, and the serum was collected by centrifugation. The small intestinal crypts of healthy C57BL/6 mice were harvested and cultivated in 3D culture system that maintaining the growth and proliferation of intestinal stem cells in vitro. In our experiment, 5%, 10%, 20% proportions of aGVHD serum were respectively added into the organoid culture system for 3 days. The formation of small intestinal organoids were observed under an inverted microscope and the morphological characteristics of intestinal organoids in each groups were analyzed. For further evaluation, the aGVHD intestinal organoids were harvested and their pathological changes were observed. Combined with HE staining, intestinal organ morphology evaluation was performed. Combined with Alcian Blue staining, the secretion function of aGVHD intestinal organoids was observed. The distribution and changes of Lgr5+ and Clu+ intestinal stem cells in intestinal organoids were analyzed under the conditions of 5%, 10% and 20% serum concentrations by immunohistochemical stainings.@*RESULTS@#The results of HE staining showed that the integrity of intestinal organoids in the 5% concentration serum group was better than that in the 10% and 20% groups. The 5% concentration serum group showed the highest number of organoids, the highest germination rate and the lowest pathological score among experimental groups, while the 20% group exhibited severe morphological destruction and almost no germination was observed, and the pathological score was the highest among all groups(t=3.668, 4.334,5.309,P<0.05). The results of Alican blue staining showed that the secretion function of intestinal organoids in serum culture of aGVHD in the 20% group was weaker than that of the 5% group and 10% of the organoids, and there was almost no goblet cells, and mucus was stainned in the 20% aGVHD serum group. The immunohistochemical results showed that the number of Lgr5+ cells of intestinal organoids in the 5% group was more than that of the intestinal organoids in the 10% aGVHD serum group and 20% aGVHD serum group. Almost no Clu+ cells were observed in the 5% group. The Lgr5+ cells in the 20% group were seriously injuried and can not be observed. The proportion of Clu+ cells in the 20% group significantly increased.@*CONCLUSION@#The concentration of aGVHD serum in the culture system can affect the number and secretion function of intestinal organoids as well as the number of intestinal stem cells in organoids. The higher the serum concentration, the greater the risk of organoid injury, which reveal the characteristics of the formation and functional change of aGVHD intestinal organoids, and provide a novel tool for the study of intestinal injury in aGVHD.

In vivo transplantation of eye organoids and application of tissue engineering scaffolds / 器官移植

Eye organoid refers to a structure that possesses resembling cell types and functions to intraocular tissues, which is induced by stem cells in vitro. Transplanting it into the body for eye repair and regeneration is one of the key research directions in regenerative medicine, which also provides a novel direction and strategy for the treatment of major blinding diseases. As a carrier of biological tissue or cell growth, tissue engineering scaffold could support in vivo transplantation of eye organoids and promote their maturation. Organic combination of eye organoids and tissue engineering is a critical approach to realize in vivo integration of eye organoids and reconstruct corresponding structures and functions. In this review, the latest research status of eye organoids and in vivo transplantation were summarized, and relevant studies of tissue engineering scaffold-assisted eye organoid transplantation were highlighted, aiming to provide ideas and reference for subsequent inter-disciplinary research of eye organoids and tissue engineering.

Establishment and application of hepatic organoid model of hepatitis B virus infection / 中华传染病杂志

Objective:To establish the hepatic organoid of hepatitis B virus (HBV) infection on the basis of induced pluripotent stem cells (iPSC) and an inverted colloidal crystal polyethylene glycol scaffold (ICC), and to evaluate the antiviral effect of nucleoside drugs.Methods:iPSC was differentiated into hepatocyte-like cells (HLC), and inoculated into ICC to construct a hepatic organoid. The relative mRNA expressions of Nanog homeobox (NANOG), sex determining region Y-box (SOX) 2, SOX17, forkhead box protein A2 (FOXA2), alpha fetoprotein (AFP) and albumin (ALB) were detected by real time quantitative polymerase chain reaction (RT-qPCR). Confocal laser microscopy was used to photograph the three-dimension (3D) structure of organs. The expression of sodium taurocholate cotransporting polypeptide (NTCP) in HLC was analyzed by Western blot and immunofluorescence. HepG2.2.15 cells were used to extract HBV virus particles to infect hepatic organoid. The relative expression of HBV pregenome RNA (pgRNA) in cells was detected by RT-qPCR. The expressions of hepatitis B core antigen (HBcAg) and hepatitis B surface antigen (HBsAg) in cytoplasm were observed under confocal laser microscopy. A total of 0.5 μmol/L entecavir and 0.5 μmol/L lamivudine were used to treat the infected cells respectively. The relative expression of HBV pgRNA in infected and uninfected cells was detected by RT-qPCR. Independent sample t test and one-way analysis of variance were used for statistical analysis. Results:Within 21 days of iPSC differentiation, the mRNA expressions of NANOG and SOX2 in stem cells markers decreased ( F=158.90 and 8.31, respectivley; P<0.001 and P=0.002, respectively), while the mRNA expressions of SOX17 and FOXA2 in the endoderm increased first and then decreased ( F=37.23 and 82.57, respectively, both P<0.001). In the later stage of differentiation, the mRNA expressions of AFP and ALB in liver cells increased ( F=4.65 and 34.64, respectively, P=0.012 and P<0.001, respectively), and all differences were statistically significant. NTCP was highly expressed in differentiated cells detected by Western blot and fluorescence microscopy, the protein expression level was 0.803±0.099. Confocal laser microscopy confirmed that the differentiated cells expressed ALB and presented spherical structure in ICC. The expression of HBV pgRNA and the immunostaining of HBsAg and HBcAg confirmed that HBV successfully infected hepatic organoid. Three days after the application of entecavir and lamivudine, the HBV pgRNA level decreased significantly both in entecavir group (0.665±0.220) and lamivudine group (0.503±0.117) compared to the uninfected cells (3.347±0.454), and the differences were both statistically significant ( t=10.53 and 12.72, respectively, both P<0.001). Conclusions:HLC display hepatic specific genes ALB and NTCP. Hepatic organoids constructed with iPSC and ICC have human liver function and can be infected by HBV. Entecavir and lamivudine could effectively inhibit the replication of HBV in hepatic organoids.

Current status of applying matrigel to in vitro models for cancer reseach / 肿瘤

The components of the tumor microenvironment have a complex composition and play an important regulatory role in tumor evolution.The extracellular matrix(ECM)serves as a vital mediator in regulating cancer advancement within the TME.Incorporating ECM into tumor modeling allows for a more comprehensive simulation of the TME in vitro.As a medium for organoid growth,the matrix gel fulfills the functions of ECM.ECM is normally derived from the recombinant basement membrane of mouse sarcoma(Matrigel);however,batch-to-batch variations in Matrigel affect experiment reproducibility.To overcome such issues,researchers have designed synthetic matrix gels.This paper provides an overview of the current research in the application of matrix gels for tumor organoid modeling,offering insights for continuous optimization of organoid culture,thereby achieving more efficient and cost-effective organoid construction and advancing the translation of basic research to clinical applications.

Implications on the Development of Animal Disease Models from FDA Modernization Act 2.0 / 实验动物与比较医学

Laboratory animals are the foundational conditions and indispensable technical support in life science research and biomedical industry development. The scientific development of animal models of diseases is of great significance to biomedical research and industrial development. In light of the booming development of multiple emerging in vitro modelling technologies over the past decade, in 2022, the U.S. Senate unanimously passed the bill FDA Modernization Act 2.0. This bill rescinded the requirement for animal testing in investigating the safety and effectiveness of a drug—a federal mandate since 1938, and highlighted the potential of various in vitro disease modeling approaches in future biomedical fields. This paper provides a comprehensive review of the latest advances and applications of in vitro disease modeling approaches in academia and industry followed by an interpretation of the FDA bill, namely cell culture, organoid, organ-on-a-chip, 3D bio-printing model and computer-based model. The paper next introduces the crossed applications of various disease models and discusses the advantages and disadvantages of each system, thereby providing insights into future trends in the use of animal disease models in China.

Developmental comparison between cerebral organoids in vitro and body's cortices in vivo / 解剖学报

Objective To understand the characteristics and developmental differences between cerebral organoids in vitro and normal cerebral cortices in vivo. Methods 1. Grouping: cerebral cortices in vivo group and cultured cerebral organoids in vitro group. 2. Sample collection: cortical tissues were collected from Kunming mouse embryos at embryonic day 7.5(E7.5), E9.5, E11.5, E14.5, and postnatal day 3 (P3) or P7. Three specimens were taken from each group. Meanwhile, cerebral organoids were cultured with mouse induced pluripotent stem cells (iPSCs), and samples at different culture time point were collected, and more than 3 samples were collected at each time point. 3. Detection method: the distribution of different types of cells in each group of specimens was analyzed by immunofluorescent staining. Results While relative similarities between in vivo cerebral cortical development and the cerebral organoids in vitro were observed, including the histogenesis, and the morphological differentiation of nerve cells and glial cells, the lamellar architecture of cerebral cortex in mouse brain was not observed in cerebral organoids. Conclusion The development of cerebral organoids in vitro has some similarity with body's cortical development. Therefore, cerebral organoids can be used to a substitution of cortex and diseases' models, but improvement of the existing technologies is necessary.

The past, present and future of heart transplantation / 器官移植

Heart transplantation is one of the most effective strategies to treat end-stage heart failure. Multiple challenges, such as difficulty in preservation of heart allograft, rejection and postoperative complications, emerge in heart allotransplantation. After decades of research and practice, most problems have been resolved. Nevertheless, the shortage of donor organs has become increasingly prominent. To alleviate the shortage of donor organs, artificial heart and heart xenotransplantation have captivated attention, and obtained significant progress in recent years. The application of artificial heart in clinical practice has significantly enhanced the survival rate of patients with end-stage heart failure, which is expected to become the standard treatment for end-stage heart failure. Heart xenotransplantation still faces many challenges, which is still far from clinical application. In this article, the history of heart transplantation, development of heart allotransplantation, use of artificial heart and research progress on heart xenotransplantation were reviewed, and the future development direction of heart transplantation was predicted.