摘要: Chemodynamic therapy (CDT) has garnered significant attention for treating diverse malignant tumours due to its minimally invasive nature, reduced damage to healthy tissues, and potential mitigation of side effects. However, its application in glioblastoma (GBM) is hindered by the diminished capacity of CDT agents to traverse the blood-brain barrier (BBB), inadequate tumour targeting efficiency, and restricted availability of H2O2 within the tumour microenvironment (TME). To address these challenges, we devised a novel CDT agent (Fe@tFNAs-ANG-3AT) based on a tetrahedral framework nucleic acids (tFNAs). Fe@tFNAs-ANG-3AT was constructed by anchoring iron ions (Fe3+) onto the dual appendages-modified tFNAs. Specifically, one appendage, Angiopep-2 (ANG, a penetrating peptide), facilitates Fe@tFNAs-ANG-3AT penetration across the BBB and selective targeting of tumour cells. Simultaneously, the second appendage, 3-Amino-1,2,4-triazole (3AT, a H2O2 enzyme inhibitor), augments the H2O2 levels required for effective CDT treatment. Upon tumour cell internalization, the loaded Fe3+ in Fe@tFNAs-ANG-3AT is reduced to Fe2+ by the overexpressed glutathione (GSH) in the TME, catalysing the generation of cytotoxic hydroxyl radicals (OH) and inducing tumour cell death via elevated oxidative stress levels within tumour cells. It is anticipated that Fe@tFNAs-ANG-3AT holds promise as a transformative treatment strategy for GBM. A novel CDT agent (Fe@tFNAs-ANG-3AT) is developed and demonstrates the capability to effectively cross the BBB and selectively accumulate in tumour cells. Upon tumour cell internalization, Fe@tFNAs-ANG-3AT can augment the H2O2 levels and react with GSH and H2O2 to generate center dot OH, thus leading to an effective CDT against GBM.image

摘要: Transglutaminase 2 (Tgm2) plays an essential role in hepatic repair following prolonged toxic injury. During cholestatic liver injury, the intrahepatic cholangiocytes undergo dynamic tissue expansion and remodelling, referred to as ductular reaction (DR), which is crucial for liver regeneration. However, the molecular mechanisms governing the dynamics of active cells in DR are still largely unclear. Here, we generated Tgm2-knockout mice (Tgm2(-/-)) and Tgm2(-CreERT2)-Rosa26-mTmG flox/flox (Tgm2(CreERT2-)R26T/G(f/f)) mice and performed a three-dimensional (3D) collagen gel culture of mouse hepatocytes to demonstrate how Tgm2 signalling is involved in DR to remodel intrahepatic cholangiocytes. Our results showed that the deletion of Tgm2 adversely affected the functionality and maturity of the proliferative cholangiocytes in DR, thus leading to more severe cholestasis during DDC-induced liver injury. Additionally, Tgm2 hepatocytes played a crucial role in the regulation of DR through metaplasia. We unveiled that Tgm2 regulated H3K4me3Q5ser via serotonin to promote BMP signalling activation to participate in DR. Besides, we revealed that the activation or inhibition of BMP signalling could promote or suppress the development and maturation of cholangiocytes in DDC-induced DR. Furthermore, our 3D collagen gel culture assay indicated that Tgm2 was vital for the development of cholangiocytes in vitro. Our results uncovered a considerable role of BMP signalling in controlling metaplasia of Tgm2 hepatocytes in DR and revealed the phenotypic plasticity of mature hepatocytes.

摘要: The objective of this study was to investigate the effects and molecular mechanisms of tetrahedral framework nucleic acids-microRNA22 (tFNAs-miR22) on inhibiting pathological retinal neovascularization (RNV) and restoring physiological retinal vessels. A novel DNA nanocomplex (tFNAs-miR22) was synthesised by modifying microRNA-22 (miR22) through attachment onto tetrahedral frame nucleic acids (tFNAs), which possess diverse biological functions. Cell proliferation, wound healing, and tube formation were employed for in vitro assays to investigate the angiogenic function of cells. Oxygen-induced retinopathy (OIR) model was utilised to examine the effects of reducing pathological neovascularization (RNV) and inhibiting vascular occlusion in vivo. In vitro, tFNAs-miR22 demonstrated the ability to penetrate endothelial cells and effectively suppress cell proliferation, tube formation, and migration in a hypoxic environment. In vivo, tFNAs-miR22 exhibited promising results in reducing RNV and promoting the restoration of normal retinal blood vessels in OIR model through modulation of the Wnt pathway. This study provided a theoretical basis for the further understanding of RNV, and highlighted the innovative and potential of tFNAs-miR22 as a therapeutic option for ischemic retinal diseases.

摘要: The decline in female fertility as age advances is intricately linked to the diminished developmental potential of oocytes. Despite this challenge, the strategies available to enhance the quality of aged oocytes remain limited. Epigallocatechin-3-gallate (EGCG), characterised by its anti-inflammatory, antioxidant and tissue protective properties, holds promise as a candidate for improving the quality of maternally aged oocytes. In this study, we explored the precise impact and underlying mechanisms of EGCG on aged oocytes. EGCG exhibited the capacity to enhance the quality of aged oocytes both in vitro and in vivo. Specifically, the application of EGCG in vitro resulted in noteworthy improvements, including an increased rate of first polar body extrusion, enhanced mitochondrial function, refined spindle morphology and a reduction in oxidative stress. These beneficial effects were further validated by the improved fertility observed among aged mice. In addition, our findings propose that EGCG might augment the expression of Arf6. This augmentation, in turn, contributes to the assembly of spindle-associated F-actin, which can contribute to mitigate the aneuploidy induced by the disruption of spindle F-actin within aged oocytes. This work thus contributes not only to understanding the role of EGCG in bolstering oocyte health, but also underscores its potential as a therapeutic intervention to address fertility challenges associated with advanced age. This study delves into the precise impact and underlying mechanisms of EGCG on aged oocytes. Both in vitro and in vivo experiments demonstrate EGCG's capacity to enhance the quality of aged oocytes. In vitro application of EGCG yields remarkable improvements, including heightened rates of first polar body extrusion, refined spindle morphology, enhanced mitochondrial function, and reduced oxidative stress. Besides, EGCG may enhance Arf6 expression through direct interaction in aged oocytes, consequently promoting the assembly of spindle-associated F-actin and mitigating the aneuploidy induced by the disruption of spindle F-actin. In addition, these positive outcomes are corroborated by enhanced fertility observed in aged mice, providing a therapeutic intervention to address fertility challenges associated with advanced age.image

摘要: Apoptotic vesicles (apoVs) are nanoscale vesicles derived from billions of apoptotic cells involved in the maintenance of the human body's homeostasis. Previous researches have shown that some apoVs, such as those derived from mesenchymal stem cells, contribute to bone formation. However, those apoVs cannot be extracted from patients in large quantities, and cell expansion is needed before apoV isolation, which limits their clinical translation. Mature RBCs, which have no nuclei or genetic material, are easy to obtain, showing high biological safety as a source of extracellular vesicles (EVs). Previous studies have demonstrated that RBC-derived EVs have multiple biological functions, but it is unknown whether RBCs produce apoVs and what effect these apoVs have on bone regeneration. In this study, we isolated and characterized RBC-derived apoVs (RBC-apoVs) from human venous blood and investigated their role in the osteogenesis of human bone mesenchymal stem cells (hBMSCs). We showed that RBCs could produce RBC-apoVs that expressed both general apoVs markers and RBC markers. RBC-apoVs significantly promoted osteogenesis of hBMSCs and enhanced bone regeneration in rat calvarial defects. Mechanistically, RBC-apoVs regulated osteogenesis by transferring carbonic anhydrase 1 (CA1) into hBMSCs and activating the P38 MAPK pathway. Our results indicated that RBC-apoVs could deliver functional molecules from RBCs to hBMSCs and promote bone regeneration, pointing to possible therapeutic use in bone tissue engineering.

摘要: Early embryonic loss, caused by reduced embryo developmental competence, is the major cause of subfertility in humans and animals. This embryo developmental competence is determined during oocyte maturation and the first embryo divisions. Therefore, it is essential to identify the underlying molecules regulating these critical developmental stages. Cathepsin L (CTSL), a lysosomal cysteine protease, is involved in regulating cell cycle progression, proliferation and invasion of different cell types. However, CTSL role in mammalian embryo development is unknown. Using bovine in vitro maturation and culture systems, we show that CTSL is a key regulator for embryo developmental competence. We employed a specific CTSL detection assay in live cells to show that CTSL activity correlates with meiotic progression and early embryo development. Inhibiting CTSL activity during oocyte maturation or early embryo development significantly impaired oocyte and embryo developmental competence as evidenced by lower cleavage, blastocyst and hatched blastocyst rates. Moreover, enhancing CTSL activity, using recombinant CTSL (rCTSL), during oocyte maturation or early embryo development significantly improved oocyte and embryo developmental competence. Importantly, rCTSL supplementation during oocyte maturation and early embryo development significantly improved the developmental competence of heat-shocked oocytes/embryos which are notoriously known for reduced quality. Altogether, these results provide novel evidence that CTSL plays a pivotal role in regulating oocyte meiosis and early embryonic development.

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摘要: To date, generating viable and functional hepatocytes in large scale remains challenge. By employing 3D suspension condition with the support of low concentration Matrigel, a novel culture system was developed to generate expandable hepatoblast organoids (HB-orgs) and mature polarised hepatocyte organoids (P-hep-orgs) from human embryonic stem cells (hESCs) in both dishes and bioreactors. scRNA-seq and functional assays were used to characterise HB-orgs and P-hep-orgs. hESC-derived HB-orgs could proliferate at least for 15 passages, leading to 1012 in total cells in 4 weeks. P-hep-orgs differentiated from HB-orgs displayed characteristics of mature hepatocytes with polarisation. Moreover, single-cell RNA sequencing exhibited that over 40% of cells in P-hep-orgs were highly fidelity with human primary hepatocytes. Eventually, large-scale production of P-hep-orgs could be generated from massively expanded HB-orgs within 1 week with similar number in bioreactors, which were achieved by the enhancements in energy metabolism contribute to the expansion of HB-orgs and maturation of P-hep-orgs in bioreactors. By providing a cost-efficient and robust platform, our study represents a significant step toward manufacturing large-scale functioning hESC-derived hepatocytes for cell-based therapeutics, disease modelling, pharmacology and toxicology studies.

摘要: Interleukin-12 (IL-12) holds significant potential in cancer therapy; however, its clinical applicability is hindered by dose-limiting toxicity. Delivery of the IL-12 gene directly to tumours for constitutive IL-12 expression is a possible strategy to enhance its effectiveness while minimizing systemic toxicity. In this study, we investigate the potential of red blood cell-derived extracellular vesicles (RBCEVs) as a carrier for Il-12 plasmid delivery. We demonstrate that RBCEVs can be loaded with minicircle plasmid encoding IL-12 and delivered to MB49 bladder cancer cells for IL-12 expression. The expression of transgenes from minicircles was significantly higher than from the parental plasmids. RBCEV-mediated IL-12 expression stimulated immune responses in mouse splenocytes. Intratumoral delivery of Il-12 plasmid-loaded RBCEVs suppressed bladder cancer tumour growth, stimulated immune responses and promoted immune cell infiltration. In conclusion, our study demonstrates the promising potential of RBCEVs as an effective, safe and redosable nucleic acid drug delivery platform for IL-12.

摘要: Memory inflation is confirmed as the most commonly dysregulation of host immunity with antigen-independent manner in mammals after viral infection. By generating large numbers of effector/memory and terminal differentiated effector memory CD8+ T cells with diminished na & iuml;ve subsets, memory inflation is believed to play critical roles in connecting the viral infection and the onset of multiple diseases. Here, we reviewed the current understanding of memory inflated CD8+ T cells in their distinct phenotypic features that different from exhausted subsets; the intrinsic and extrinsic roles in regulating the formation of memory inflation; and the key proteins in maintaining the expansion and proliferation of inflationary populations. More importantly, based on the evidences from both clinic and animal models, we summarized the potential mechanisms of memory inflation to trigger autoimmune neuropathies, such as Guillain-Barr & eacute; syndrome and multiple sclerosis; the correlations of memory inflation between tumorigenesis and resistance of tumour immunotherapies; as well as the effects of memory inflation to facilitate vascular disease progression. To sum up, better understanding of memory inflation could provide us an opportunity to beyond the acute phase of viral infection, and shed a light on the long-term influences of CD8+ T cell heterogeneity in dampen host immune homeostasis. This review highlights the definition of virus-induced CD8+ T cell memory inflation, as well as the impacts on multi-diseases progression. By summarizing current understandings, an opportunity is provided for shedding a light on the long-term influences of memory inflation in host-immune homeostasis thus beyond the acute phase of infection. image