Hypoxic injury (HI) in the prenatal period often causes neonatal neurological disabilities. Due to the difficulty in obtaining clinical samples, the molecular and cellular mechanisms remain unclear. Here we use vascularized cerebral organoids to investigate the hypoxic injury phenotype and explore the intercellular interactions between vascular and neural tissues under hypoxic conditions. Our results indicate that fused vascularized cerebral organoids exhibit broader hypoxic responses and larger decreases in panels of neural development-related genes when exposed to low oxygen levels compared to single cerebral organoids. Interestingly, vessels also exhibit neural protective effects on T-box brain protein 2⁺ intermediate progenitors (IPs), which are markedly lost in HI cerebral organoids. Furthermore, we identify the role of bone morphogenic protein signaling in protecting IPs. Thus, this study has established an in vitro organoid system that can be used to study the contribution of vessels to brain injury under hypoxic conditions and provides a strategy for the identification of intervention targets.
Organoids/pathology* ; Animals ; Mice ; Hypoxia, Brain/metabolism* ; Brain/blood supply* ; Neurons/metabolism*

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

OBJECTIVE: To elucidate the molecular mechanisms underlying sepsis-induced injury in mouse intestinal organoids and investigate the possible mechanisms or potential drug targets of myeloid differentiation factor 88 inhibitor [TJ-M2010-5 (TJ5)] on this condition. METHODS: Small intestinal organoids from C57BL/6 mice aged 6-8 weeks were established and characterized using immunofluorescence for cell growth and proliferation marker nuclear antigen Ki-67, goblet cell marker mucin-2 (MUC-2), epithelial cell marker E-cadherin, and Paneth cell marker lysozyme (Lyz). Small intestinal organoids after 3 days of passaging were divided into different groups: a normal control group treated with culture medium containing 0.2% dimethyl sulfoxide (DMSO) for 10 hours, a lipopolysaccharide (LPS) group treated with culture medium containing 200 mg/L LPS and 0.2% DMSO for 10 hours, and a TJ5 group pre-treated with 10 mmol/L TJ5 for 2 hours followed by treatment with culture medium containing 200 mg/L LPS for 10 hours. Real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was used to measure the expression levels of interleukin-6 (IL-6) and zonula occludens-1 (ZO-1) in the small intestinal organoids. RNA transcriptome sequencing was performed on the small intestinal organoids from each group to analyze differentially expressed genes between groups, and significant enrichment was analyzed using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). RESULTS: By the 7th day of primary culture, mature organoids had formed, and their growth rate increased after passaging. Immunofluorescence identification showed expressions of Ki-67, MUC-2, E-cadherin, and Lyz, indicating that the mouse small intestinal organoids maintained their cellular composition and functional characteristics under in vitro culture conditions. RT-qPCR results showed that compared with the normal control group, the mRNA expression of IL-6 in the small intestinal organoids of the LPS group was significantly increased (2^-ΔΔCT: 1.83±0.16 vs. 1.02±0.28, P < 0.05), while the mRNA expression of ZO-1 was significantly decreased (2^-ΔΔCT: 0.53±0.11 vs. 1.01±0.18, P < 0.05). In contrast, the mRNA expression trends of both IL-6 and ZO-1 were reversed in the TJ5 group, showing statistically significant differences as compared with the LPS group (2^-ΔΔCT: IL-6 mRNA was 1.24±0.01 vs. 1.83±0.16, ZO-1 mRNA was 1.97±0.29 vs. 0.53±0.11, both P < 0.05). RNA transcriptome sequencing showed 49 differentially expressed genes in the LPS group compared to the normal control group, with 42 upregulated and 7 downregulated. Compared to the LPS group, the TJ5 group showed 84 differentially expressed genes, with 47 upregulated and 37 downregulated. GO enrichment analysis of these differentially expressed genes showed that the significantly enriched biological processes of the differentially expressed genes between the normal control group and the LPS group included responses to LPS, responses to molecule of bacterial origin and responses to bacterium. The significantly enriched biological processes of the differentially expressed genes between the LPS group and the TJ5 group included glutathione metabolic processes, responses to stress cellular and responses to chemical stimulus. In molecular function groups, glutathione binding and oligopeptide binding were significantly enriched by the differentially expressed genes. In cellular component classifications, the enrichment of the differentially expressed genes was mainly observed in the cytoplasm, endoplasmic reticulum, and microsomes. KEGG pathway enrichment analysis indicated that the differentially expressed genes between the normal control group and LPS group were enriched in IL-17 signaling pathways, tumor necrosis factor (TNF) signaling pathways, viral protein interactions with cytokines and cytokine receptors signaling pathways, and cytokine-cytokine receptor interaction signaling pathways. In contrast, the differentially expressed genes between the LPS and TJ5 groups were mainly enriched in atherosclerosis signaling pathways, ferroptosis signaling pathways, glutathione metabolism signaling pathways, and cytochrome P450-mediated drug metabolism signaling pathways. CONCLUSIONS Mouse small intestinal organoids were successfully extracted and cultured. TJ5 may exert its protective effects by regulating gene expression and related signaling pathways (fluid shear stress and atherosclerosis, ferroptosis, glutathione metabolism, cytochrome P450 drug metabolism, etc.) in sepsis-injured mouse small intestinal organoids. These genes and signaling pathways may be key targets for treating sepsis-induced intestinal injury.
Animals ; Mice ; Sepsis/genetics* ; Organoids/drug effects* ; Mice, Inbred C57BL ; Intestine, Small/metabolism* ; Gene Expression Profiling ; Transcriptome ; Lipopolysaccharides

Embryo implantation involves a complex interaction between the embryo and the endometrium of the mother, the study of which faces a variety of problems. The modeling of endometrial epithelial organoids and endometrial assembloids provides a new way to study the process of embryo implantation in vitro. This paper summarized the latest research progress in embryo implantation, the regulation mechanism of endometrial receptivity by estrogen- progesterone coordination and embryo-derived signals, the establishment of endometrial organoids, and the development and application of endometrial assembloids in the research on mother-embryo interaction, providing new strategies for studying the communication between embryo and maternal uterus during implantation.
Endometrium/physiology* ; Organoids/cytology* ; Embryo Implantation/physiology* ; Female ; Animals ; Progesterone/pharmacology* ; Pregnancy ; Estrogens/metabolism* ; Humans

In order to establish a stable in vitro culture platform for chicken small intestine three-dimensional (3D) organoids, in this study, crypt cells were collected from the small intestine of 18-day-old embryos of AA broilers. On the basis of the L-WRN conditioned medium, we optimized the culture conditions of chicken small intestinal organoids by adjusting the proportions of nicotinamide, N-acetylcysteine, LY2157299, CHIR99021, Jagged-1, FGF, and other cytokines to select the medium suitable for the long-term stable growth of the organoids. The optimization results showed that the addition of 1.5 µmol/L CHIR99021 significantly improved the organoid formation efficiency and organoid diameter. When 0.5 µmol/L Jagged-1 was added, a small amount of bud-like tissue appeared in organoids. After the addition of 50 ng/mL FGF-2, the rate of organoid germination was significantly increased. The 1.5 µmol/L CHIR99021, 0.5 µmol/L Jagged-1, and 50 ng/mL FGF-2 added in the medium can cooperate with each other to improve the formation and speed up the proliferation and differentiation of organoids, while improving the stemness maintenance of cells. The morphology, cell types, and culture characteristics of chicken small intestinal organoids were studied by HE staining, transmission electron microscopy, reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), indirect immunofluorescence, and immunohistochemistry. The results showed that the 3D organoids of the chicken small intestine cultured in vitro were morphologically consistent with the chicken intestinal tissue and contained differentiated epithelial cells. In summary, we successfully established an in vitro culture system for chicken small intestinal organoids, providing a new method for the subsequent research on chicken intestinal physiology, pathology, and host-pathogen interaction mechanism and the development of relevant drugs.
Animals ; Organoids/metabolism* ; Intestine, Small/drug effects* ; Chickens ; Cell Culture Techniques/methods* ; Culture Media ; Chick Embryo ; Tissue Culture Techniques/methods*

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.
Humans ; Olfactory Mucosa/metabolism* ; Epithelial Cells ; Organoids/metabolism* ; Olfaction Disorders/metabolism*

Ameloblasts are specialized cells derived from the dental epithelium that produce enamel, a hierarchically structured tissue comprised of highly elongated hydroxylapatite (OHAp) crystallites. The unique function of the epithelial cells synthesizing crystallites and assembling them in a mechanically robust structure is not fully elucidated yet, partly due to limitations with in vitro experimental models. Herein, we demonstrate the ability to generate mineralizing dental epithelial organoids (DEOs) from adult dental epithelial stem cells (aDESCs) isolated from mouse incisor tissues. DEOs expressed ameloblast markers, could be maintained for more than five months (11 passages) in vitro in media containing modulators of Wnt, Egf, Bmp, Fgf and Notch signaling pathways, and were amenable to cryostorage. When transplanted underneath murine kidney capsules, organoids produced OHAp crystallites similar in composition, size, and shape to mineralized dental tissues, including some enamel-like elongated crystals. DEOs are thus a powerful in vitro model to study mineralization process by dental epithelium, which can pave the way to understanding amelogenesis and developing regenerative therapy of enamel.
Mice ; Animals ; Durapatite/metabolism* ; Dental Enamel/metabolism* ; Ameloblasts/metabolism* ; Amelogenesis ; Stem Cells ; Organoids

The purpose of this study was to establish a three-dimensional (3D) organoid culture system for type 2 alveolar epithelial (AT2) cells in mice. AT2 cells were isolated from ICR mouse lung and purified by enzymatic digestion and MicroBeads sorting. The purity of AT2 cells was determined by immunofluorescence (IF) staining using an antibody against proSPC. The AT2 differentiation was examined by IF staining with proSPC/HopX and proSPC/T1α antibodies, and proliferation of AT2 cells was assessed by EdU incorporation assays after two-dimensional (2D) culture for 8 days. In addition, AT2 cells were co-cultured with mouse lung fibroblasts (Mlg) in three-dimensional (3D) culture system. After 13 days of co-culture, the organoids were fixed in 2% paraformaldehyde for histological analysis and IF staining. The results showed that the purity of the AT2 cells was over 95%, as assessed by proSPC staining. 2D cultured AT2 cells were negative for EdU staining, which indicates that no proliferation occurs. proSPC expression was gradually disappeared, whereas T1α and HopX expression was gradually increased after 3, 5 and 8 days of culture. In 3D culture system, the alveolar organoids were formed after co-culturing AT2 cells with Mlg for 4 days. Histological analysis showed that alveolar organoids displayed a hollow morphology. proSPC was highly expressed in the peripheral cells, whereas type 1 alveolar epithelial (AT1) cells transdifferentiated from AT2 cells expressing HopX were mainly located in the interior of organoid bodies after 13 days. Some of the proSPC-positive AT2 cells located in the outer circle of alveolar organoids were stained positive for both proSPC and EdU, indicating that the AT2 cells in the alveolar organoids were proliferative. These results showed that the 3D organoid culture system of mouse AT2 cells was successfully established.
Alveolar Epithelial Cells/metabolism* ; Animals ; Cell Differentiation ; Cells, Cultured ; Epithelial Cells ; Lung ; Mice ; Mice, Inbred ICR ; Organoids

Betacoronavirus ; isolation & purification ; pathogenicity ; Bile Acids and Salts ; metabolism ; Bile Ducts, Intrahepatic ; pathology ; virology ; Cell Culture Techniques ; Coronavirus Infections ; complications ; pathology ; Cytokine Release Syndrome ; etiology ; physiopathology ; Cytopathogenic Effect, Viral ; Epithelial Cells ; enzymology ; pathology ; virology ; Humans ; Hyperbilirubinemia ; etiology ; Liver ; pathology ; Organoids ; pathology ; virology ; Pandemics ; Peptidyl-Dipeptidase A ; analysis ; Pneumonia, Viral ; complications ; pathology ; Receptors, Virus ; analysis ; Serine Endopeptidases ; analysis ; Viral Load

Precision medicine emerges as a new approach that takes into account individual variability. Successful realization of precision medicine requires disease models that are able to incorporate personalized disease information and recapitulate disease development processes at the molecular, cellular and organ levels. With recent development in stem cell field, a variety of tissue organoids can be derived from patient specific pluripotent stem cells and adult stem cells. In combination with the state-of-the-art genome editing tools, organoids can be further engineered to mimic disease-relevant genetic and epigenetic status of a patient. This has therefore enabled a rapid expansion of sophisticated in vitro disease models, offering a unique system for fundamental and biomedical research as well as the development of personalized medicine. Here we summarize some of the latest advances and future perspectives in engineering stem cell organoids for human disease modeling.
Animals ; Biomedical Research ; Gene Editing ; methods ; Humans ; Models, Biological ; Organoids ; metabolism ; Pluripotent Stem Cells ; metabolism ; Precision Medicine ; methods