METHODS: Cardiac organoids derived from the self-assembled human induced pluripotent stem cells were constructed by regulating the Wnt signaling pathway. Flow cytometry was used to detect the proportion of cardiomyocytes in the cardiac organoids, and RT-qPCR was employed to detect the mRNA expressions. Immunofluorescence staining was used to detect the protein expressions of TNNT2, CD31, and vimentin. The beating amplitude of the cardiac organoids was determined with calcium transient. In vitro myocardial injury models and ischemia-reperfusion models were established, and the cell injuries were examined using Masson staining. TUNEL staining and calcium transient detection were used to evaluate the adverse effects of doxorubicin and trastuzumab in the cardiac organoids. RESULTS: The cardiac organoids began to beat on the 8th day of culture and consisted of 32.4% cardiomyocytes with high expressions of the myocardial markers TNNT2, NKX2.5, RYR2 and KCNJ2. No significant differences in morphological size, beating frequency, proportion of cardiomyocytes, or myocardial contractility were observed in the cardiac organoids differentiated from different batches. These cardiac organoids could be maintained in in vitro culture conditions for at least 50 days. Captopril treatment could obviously alleviate liquid nitrogen-induced myocardial injury in the cardiac organoids. Hypoxia/reoxygenation induced ischemia-reperfusion injury and promoted myocardial fibrosis and apoptosis in the cardiac organoids. Treatment with doxorubicin for 24 h resulted in significantly increased cell death and reduced beating frequency and cell viability in the cardiac organoids in a dose-dependent manner. Trastuzumab significantly impaired the contractile and calcium handling abilities of the cardiac organoids. CONCLUSIONS Cardiac organoids derived from human induced pluripotent stem cells have been successfully constructed and can be used for cardiac disease modeling and drug evaluation.
Humans ; Induced Pluripotent Stem Cells/cytology* ; Organoids/cytology* ; Myocytes, Cardiac/cytology* ; Cell Differentiation ; Heart Diseases

Frostbite is the most common cold injury and is caused by both immediate cold-induced cell death and the gradual development of localized inflammation and tissue ischemia. Delayed healing of frostbite often leads to scar formation, which not only causes psychological distress but also tends to result in the development of secondary malignant tumors. Therefore, a rapid healing method for frostbite wounds is urgently needed. Herein, we used a mouse skin model of frostbite injury to evaluate the recovery process after frostbite. Moreover, single-cell transcriptomics was used to determine the patterns of changes in monocytes, macrophages, epidermal cells, and fibroblasts during frostbite. Most importantly, human-induced pluripotent stem cell (hiPSC)-derived skin organoids combined with gelatin-hydrogel were constructed for the treatment of frostbite. The results showed that skin organoid treatment significantly accelerated wound healing by reducing early inflammation after frostbite and increasing the proportions of epidermal stem cells. Moreover, in the later stage of wound healing, skin organoids reduced the overall proportions of fibroblasts, significantly reduced fibroblast-to-myofibroblast transition by regulating the integrin α5β1-FAK pathway, and remodeled the extracellular matrix (ECM) through degradation and reassembly mechanisms, facilitating the restoration of physiological ECM and reducing the abundance of ECM associated with abnormal scar formation. These results highlight the potential application of organoids for promoting the reversal of frostbite-related injury and the recovery of skin functions. This study provides a new therapeutic alternative for patients suffering from disfigurement and skin dysfunction caused by frostbite.
Animals ; Organoids/metabolism* ; Mice ; Humans ; Wound Healing ; Frostbite/metabolism* ; Skin/pathology* ; Induced Pluripotent Stem Cells/cytology* ; Cicatrix/pathology* ; Fibroblasts/metabolism* ; Disease Models, Animal ; Mice, Inbred C57BL ; Extracellular Matrix/metabolism* ; Male

In multiple areas such as science, technology, and economic activities, it is necessary to unify the management of repetitive tasks or concepts by standardization to obtain the best order and high efficiency. Organoids, as living tissue models, have rapidly developed in the past decade. Organoids can be used repetitively for in vitro culture, cryopreservation, and recovery for further utilization. Because organoids can recapitulate the parental tissues' morphological phenotypes, cell functions, biological behaviors, and genomic profiles, they are known as renewable "living biobanks". Organoids cover two mainstream fields: Adult stem cell-derived organoids (also known as patient-derived organoids) and induced pluripotent stem cell-derived and/or embryonic stem cell-derived organoids. Given the increasing importance of organoids in the development of new drugs, standardized operation, and management in all steps of organoid construction is an important guarantee to ensure the high quality of products. In this review, we systematically introduce the standardization of organoid construction operation procedures, the standardization of laboratory construction, and available standardization documents related to organoid culture that have been published so far. We also proposed the challenges and prospects in this field.
Organoids ; Humans ; Biological Specimen Banks/standards* ; Induced Pluripotent Stem Cells/cytology* ; Cryopreservation/methods*

At present, it is generally believed that the paracrine effect of stem cells in the repair of myocardial injury is one of the important ways for stem cell therapy. Exosomes are phospholipid bilayer-enclosed nanovesicles that secreted by cells under physiological and pathological conditions. Cargo loaded into exosomes including protein, lipids and nucleic acids can be delivered to recipient cells. Therefore, exosomes are recognized as important mediators for intercellular communication. It has been suggested that exosomes from stem cells (eg. embryonic stem cells, induced pluripotent stem cells, cardiac progenitor cells, mesenchymal stem cells and cardiosphere-derived cells) have protective effects against heart injury. In this review, we summarized recent research progresses on stem cell-derived exosomes in myocardial injury, including the therapeutic effects and mechanism.
Cell Communication ; Exosomes ; physiology ; Heart Injuries ; Humans ; Induced Pluripotent Stem Cells ; cytology ; Mesenchymal Stem Cells ; cytology

Mitochondrial diseases are maternally inherited heterogeneous disorders that are primarily caused by mitochondrial DNA (mtDNA) mutations. Depending on the ratio of mutant to wild-type mtDNA, known as heteroplasmy, mitochondrial defects can result in a wide spectrum of clinical manifestations. Mitochondria-targeted endonucleases provide an alternative avenue for treating mitochondrial disorders via targeted destruction of the mutant mtDNA and induction of heteroplasmic shifting. Here, we generated mitochondrial disease patient-specific induced pluripotent stem cells (MiPSCs) that harbored a high proportion of m.3243A>G mtDNA mutations and caused mitochondrial encephalomyopathy and stroke-like episodes (MELAS). We engineered mitochondrial-targeted transcription activator-like effector nucleases (mitoTALENs) and successfully eliminated the m.3243A>G mutation in MiPSCs. Off-target mutagenesis was not detected in the targeted MiPSC clones. Utilizing a dual fluorescence iPSC reporter cell line expressing a 3243G mutant mtDNA sequence in the nuclear genome, mitoTALENs displayed a significantly limited ability to target the nuclear genome compared with nuclear-localized TALENs. Moreover, genetically rescued MiPSCs displayed normal mitochondrial respiration and energy production. Moreover, neuronal progenitor cells differentiated from the rescued MiPSCs also demonstrated normal metabolic profiles. Furthermore, we successfully achieved reduction in the human m.3243A>G mtDNA mutation in porcine oocytes via injection of mitoTALEN mRNA. Our study shows the great potential for using mitoTALENs for specific targeting of mutant mtDNA both in iPSCs and mammalian oocytes, which not only provides a new avenue for studying mitochondrial biology and disease but also suggests a potential therapeutic approach for the treatment of mitochondrial disease, as well as the prevention of germline transmission of mutant mtDNA.
Animals ; DNA, Mitochondrial ; genetics ; Humans ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; MELAS Syndrome ; genetics ; Male ; Mice ; Microsatellite Repeats ; genetics ; Mitochondria ; genetics ; metabolism ; Mutation ; genetics

Tissue damage induces cells into reprogramming-like cellular state, which contributes to tissue regeneration. However, whether factors promoting the cell reprogramming favor tissue regeneration remains elusive. Here we identified combination of small chemical compounds including drug cocktails robustly promoting in vitro cell reprogramming. We then administrated the drug cocktails to mice with acute liver injuries induced by partial hepatectomy or toxic treatment. Our results demonstrated that the drug cocktails which promoted cell reprogramming in vitro improved liver regeneration and hepatic function in vivo after acute injuries. The underlying mechanism could be that expression of pluripotent genes activated after injury is further upregulated by drug cocktails. Thus our study offers proof-of-concept evidence that cocktail of clinical compounds improving cell reprogramming favors tissue recovery after acute damages, which is an attractive strategy for regenerative purpose.
Animals ; Cellular Reprogramming ; drug effects ; Cellular Reprogramming Techniques ; methods ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; Mice

Animals ; Cellular Reprogramming ; genetics ; DNA Transposable Elements ; genetics ; Genetic Vectors ; genetics ; Genome ; genetics ; Humans ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; Mutagenesis

The development of a cerebral organoid culture in vitro offers an opportunity to generate human brain-like organs to investigate mechanisms of human disease that are specific to the neurogenesis of radial glial (RG) and outer radial glial (oRG) cells in the ventricular zone (VZ) and subventricular zone (SVZ) of the developing neocortex. Modeling neuronal progenitors and the organization that produces mature subcortical neuron subtypes during early stages of development is essential for studying human brain developmental diseases. Several previous efforts have shown to grow neural organoid in culture dishes successfully, however we demonstrate a new paradigm that recapitulates neocortical development process with VZ, OSVZ formation and the lamination organization of cortical layer structure. In addition, using patient-specific induced pluripotent stem cells (iPSCs) with dysfunction of the Aspm gene from a primary microcephaly patient, we demonstrate neurogenesis defects result in defective neuronal activity in patient organoids, suggesting a new strategy to study human developmental diseases in central nerve system.
Action Potentials ; physiology ; Biomarkers ; metabolism ; Cell Culture Techniques ; Embryoid Bodies ; cytology ; metabolism ; Gene Expression ; Humans ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; Lateral Ventricles ; cytology ; growth & development ; metabolism ; Microcephaly ; genetics ; metabolism ; pathology ; Models, Biological ; Mutation ; Neocortex ; cytology ; growth & development ; metabolism ; Nerve Tissue Proteins ; deficiency ; genetics ; Neurogenesis ; genetics ; Neurons ; cytology ; metabolism ; Organoids ; cytology ; metabolism ; PAX6 Transcription Factor ; genetics ; metabolism ; Patch-Clamp Techniques ; SOXB1 Transcription Factors ; genetics ; metabolism ; Zonula Occludens-1 Protein ; genetics ; metabolism

Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), have the potential of differentiating into all types of adult cells. Today, mature functional sperm can be derived from mouse PSCs in vitro, and meanwhile primordial germ cells (PGCs) and meiotic prophase sperm cells can be generated from human ESCs/iPSCs (hESCs/hiPSCs). It is proposed that non-genetic azoospermia might be cured if functional sperm could be obtained from human PSCs (hPSCs) in vitro. It is also possible that healthy functional sperm could be derived from the patient with genetic factor-induced azoospermia by combining iPSCs and gene editing technology. IPSC-derived functional sperm have a higher clinical value for the avoidance of the sperm source and the issue of medical ethics. This article summarizes recent advances in the differentiation of PSCs into male germ cells in vitro, aiming to provide some reference for the treatment of male infertility with PSCs.
Animals ; Cell Differentiation ; Embryonic Stem Cells ; cytology ; Humans ; Induced Pluripotent Stem Cells ; cytology ; Infertility, Male ; therapy ; Male ; Meiosis ; Mice ; Pluripotent Stem Cells ; cytology ; Spermatozoa ; cytology

Muscle atrophy caused by nerve injury is a common and difficult clinical problem. The development of stem cell researches has opened up a new way for the treatment of nerve injury-induced muscle atrophy. The induced pluripotent stem cells(iPSCs)can differentiate into various types of cells and have more advantages than embryonic stem cells (ESCs). After being transplanted into the damaged area, iPSCs are guided by neurogenic signals to the lesion sites, to repair the damaged nerve, promote generation of axon myelination, rebuild neural circuits and restore physiological function. Meanwhile, iPSCs can also differentiate into muscle cells and promote muscle tissue regeneration. Therefore, it would be possible to attenuate muscle atrophy caused by nerve injury with iPSCs treatment.
Animals ; Disease Models, Animal ; Embryonic Stem Cells ; Humans ; Induced Pluripotent Stem Cells ; cytology ; transplantation ; Muscular Atrophy ; therapy