Graphene oxide quantum dots (GOQDs) are usually prepared using expensive carbon precursors such as carbon nanotubes (CNT) or graphene under the strong acidic condition, which requires an additional ...purifying process. Here, we first develop a facile pulsed laser ablation in liquid (PLAL) technique for preparing GOQDs using earth-abundant and low-cost coal as a precursor. Only ethanol and coal are used to produce GOQDs with excellent optical properties. The prepared GOQDs exhibit excellent optoelectronic properties which can be successfully utilized in bioimaging applications.
Human pluripotent stem cell (hPSC)-derived intestinal organoids (hIOs) form 3D structures organized into crypt and villus domains, making them an excellent in vitro model system for studying human ...intestinal development and disease. However, hPSC-derived hIOs still require in vivo maturation to fully recapitulate adult intestine, with the mechanism of maturation remaining elusive. Here, we show that the co-culture with human T lymphocytes induce the in vitro maturation of hIOs, and identify STAT3-activating interleukin-2 (IL-2) as the major factor inducing maturation. hIOs exposed to IL-2 closely mimic the adult intestinal epithelium and have comparable expression levels of mature intestinal markers, as well as increased intestine-specific functional activities. Even after in vivo engraftment, in vitro-matured hIOs retain their maturation status. The results of our study demonstrate that STAT3 signaling can induce the maturation of hIOs in vitro, thereby circumventing the need for animal models and in vivo maturation.
Akkermansia muciniphila has received great attention because of its beneficial roles in gut health by regulating gut immunity, promoting intestinal epithelial development, and improving barrier ...integrity. However, A. muciniphila-derived functional molecules regulating gut health are not well understood. Microbiome-secreted proteins act as key arbitrators of host-microbiome crosstalk through interactions with host cells in the gut and are important for understanding host-microbiome relationships. Herein, we report the biological function of Amuc_1409, a previously uncharacterised A. muciniphila-secreted protein. Amuc_1409 increased intestinal stem cell (ISC) proliferation and regeneration in ex vivo intestinal organoids and in vivo models of radiation- or chemotherapeutic drug-induced intestinal injury and natural aging with male mice. Mechanistically, Amuc_1409 promoted E-cadherin/β-catenin complex dissociation via interaction with E-cadherin, resulting in the activation of Wnt/β-catenin signaling. Our results demonstrate that Amuc_1409 plays a crucial role in intestinal homeostasis by regulating ISC activity in an E-cadherin-dependent manner and is a promising biomolecule for improving and maintaining gut health.
Abstract
Human pluripotent stem cell (hPSC)-derived organoids and cells have similar characteristics to human organs and tissues. Thus, in vitro human organoids and cells serve as a superior ...alternative to conventional cell lines and animal models in drug development and regenerative medicine. For a simple and reproducible analysis of the quality of organoids and cells to compensate for the shortcomings of existing experimental validation studies, a quantitative evaluation method should be developed. Here, using the GTEx database, we construct a quantitative calculation system to assess similarity to the human organs. To evaluate our system, we generate hPSC-derived organoids and cells, and detected organ similarity. To facilitate the access of our system by researchers, we develop a web-based user interface presenting similarity to the appropriate organs as percentages. Thus, this program could provide valuable information for the generation of high-quality organoids and cells and a strategy to guide proper lineage-oriented differentiation.
► B-doped GOs are fabricated by annealing the films, which were obtained from the suspensions with GO and H3BO3. ► Raman spectra revealed more graphitization of the B-doped GO, due to B-doping ...effect. ► PL intensity of GO was decreased by B doping, presumably due to the B-induced graphitization.
We prepared boron (B)-doped graphene oxides (GOs) by means of annealing the films, which were obtained from the suspensions of GO and H3BO3 in N,N-Dimethylformamide solvent. The interplanar spacing of as-synthesized GO in X-ray diffraction spectra has been reduced by the thermal annealing at 1100°C. First-order Raman spectra revealed that the intensity ratio of the D and G bands of B-doped GO was significantly lower than those of as-synthesized and annealed GOs, suggesting more graphitization of the B-doped GO due to doping effect. The C1s X-ray photoelectron spectroscopy (XPS) of B-doped GO films not only indicated that considerable amount of functional groups has been removed but also exhibited the peak of CB band at around 283.7eV. Additionally, the B1s XPS spectrum of B-doped GOs could be deconvoluted into several peaks centered at 187.2, 188.9, 190.3, 192.0 and 193.7eV, being attributed to the presence of B atom in B4C, B-sub-C, BC2O, BCO2 and B2O3, respectively. Comparison of the photoluminescence spectra of B-doped GO with that of 1100°C-annealed GO indicated that the overall intensity was decreased, presumably due to the B-induced graphitization. An additional band at around 600–700nm from B-doped GO is attributed to the generated boron carbide phases.
Three-dimensional human intestinal organoids (hIO) are widely used as a platform for biological and biomedical research. However, reproducibility and challenges for large-scale expansion limit their ...applicability. Here, we establish a human intestinal stem cell (ISC) culture method expanded under feeder-free and fully defined conditions through selective enrichment of ISC populations (ISC
) within hIO derived from human pluripotent stem cells. The intrinsic self-organisation property of ISC
, combined with air-liquid interface culture in a minimally defined medium, forces ISC
to differentiate into the intestinal epithelium with cellular diversity, villus-like structure, and barrier integrity. Notably, ISC
is an ideal cell source for gene editing to study ISC biology and transplantation for intestinal diseases. We demonstrate the intestinal epithelium differentiated from ISC
as a model system to study severe acute respiratory syndrome coronavirus 2 viral infection. ISC
culture technology provides a biological tool for use in regenerative medicine and disease modelling.
Nitrogen (N) was doped into graphene oxide (GO) films at temperatures of 600–900°C under the flow of a mixture of NH3 and Ar. The N (atomic) concentration was varied in the range of 3.63–7.45%. XPS ...and FTIR spectra show that there are mainly single C–N and double CN bonds in the GO sheet. Raman spectra indicate that the G band becomes closer to the position of the G band of graphite with increasing doping temperature, and thus reveal that N doping produces a blue-shift of the G-band. In room-temperature photoluminescence (PL) spectra, N-doping produces an increase not only in the overall PL intensity, but also in the wavelength of the peak maxima. The shift of the induced PL of N-doped graphene is attributed mainly to the increased number of graphitic (or quaternary) N.
Cardiac fibrosis is the most common pathway of many cardiac diseases. To date, there has been no suitable in vitro cardiac fibrosis model that could sufficiently mimic the complex environment of the ...human heart. Here, a three-dimensional (3D) cardiac sphere platform of contractile cardiac microtissue, composed of human embryonic stem cell (hESC)-derived cardiomyocytes (CMs) and mesenchymal stem cells (MSCs), is presented to better recapitulate the human heart.
We hypothesized that MSCs would develop an in vitro fibrotic reaction in response to treatment with transforming growth factor-β1 (TGF-β1), a primary inducer of cardiac fibrosis. The addition of MSCs improved sarcomeric organization, electrophysiological properties, and the expression of cardiac-specific genes, suggesting their physiological relevance in the generation of human cardiac microtissue model in vitro. MSCs could also generate fibroblasts within 3D cardiac microtissues and, subsequently, these fibroblasts were transdifferentiated into myofibroblasts by the exogenous addition of TGF-β1. Cardiac microtissues displayed fibrotic features such as the deposition of collagen, the presence of numerous apoptotic CMs and the dissolution of mitochondrial networks. Furthermore, treatment with pro-fibrotic substances demonstrated that this model could reproduce key molecular and cellular fibrotic events.
This highlights the potential of our 3D cardiac microtissues as a valuable tool for manifesting and evaluating the pro-fibrotic effects of various agents, thereby representing an important step forward towards an in vitro system for the prediction of drug-induced cardiac fibrosis and the study of the pathological changes in human cardiac fibrosis.
Advanced technologies are required for generating human intestinal epithelial cells (hIECs) harboring cellular diversity and functionalities to predict oral drug absorption in humans and study normal ...intestinal epithelial physiology. We developed a reproducible two-step protocol to induce human pluripotent stem cells to differentiate into highly expandable hIEC progenitors and a functional hIEC monolayer exhibiting intestinal molecular features, cell type diversity, and high activities of intestinal transporters and metabolic enzymes such as cytochrome P450 3A4 (CYP3A4). Functional hIECs are more suitable for predicting compounds metabolized by CYP3A4 and absorbed in the intestine than Caco-2 cells. This system is a step toward the transition from three-dimensional (3D) intestinal organoids to 2D hIEC monolayers without compromising cellular diversity and function. A physiologically relevant hIEC model offers a novel platform for creating patient-specific assays and support translational applications, thereby bridging the gap between 3D and 2D culture models of the intestine.
Human intestinal organoids (hIOs), which resemble the human intestine structurally and physiologically, have emerged as a new modality for the study of the molecular and cellular biology of the ...intestine in vitro. We recently developed an in vitro maturation technique for generating functional hIOs from human pluripotent stem cells (hPSCs). Here, we investigated the function of STAT3 for inducing in vitro maturation of hIOs. This was accompanied by the tyrosine phosphorylation of STAT3, whereas treatment with pharmacological inhibitors of STAT3 suppressed the phosphorylation of STAT3 and the expression of intestinal maturation markers. We generated and characterized STAT3 knockout (KO) human embryonic stem cell (hESC) lines using CRISPR/Cas9-mediated gene editing. We found that STAT3 KO does not affect the differentiation of hESCs into hIOs but rather affects the in vitro maturation of hIOs. STAT3 KO hIOs displayed immature morphologies with decreased size and reduced budding in hIOs even after in vitro maturation. STAT3 KO hIOs showed markedly different profiles from hIOs matured in vitro and human small intestine. Additionally, STAT3 KO hIOs failed to maintain upon in vivo transplantation. This study reveals a core signaling pathway consisting of STAT3 controlling the in vitro maturation of hIOs derived from hPSCs.
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