Stem Cells Translational Medicine最新文献

We previously have shown the potential of human endomyocardial biopsy (EMB)-derived cardiac adherent proliferating cells (CardAPs) as a new cell-therapeutic treatment option for virus-induced myocarditis. To overcome the limited cell yield per EMB, CardAPs have been isolated from the human right atrial appendage (RAA) in view of allogeneic application and off-the-shelf use. We aimed to investigate the cardioprotective and immunomodulatory potential of RAA-CardAPs in experimental acute and chronic Coxsackievirus B3 (CVB3)-induced myocarditis upon injection in the viral and inflammatory phase. In the acute model, male C57BL6/J mice were intraperitoneally (i.p.) injected with the CVB3 Nancy strain or phosphate buffered saline (PBS). One day after infection, mice were intravenously (i.v.) injected with RAA-CardAPs, EMB-CardAPs (as reference cells) or PBS. For the chronic model, male Naval Medical Research Institute mice were i.p. injected with the CVB3 31-1-93 strain or PBS. Ten days after infection, mice were i.v. injected with RAA-CardAPs. Cardiac function was characterized, followed by harvest of the left ventricle (LV) and spleen for subsequent analysis, 7 and 28 days after CVB3 infection in the acute and chronic model, respectively. In the acute model, RAA-CardAPs decreased cardiac fibrosis and improved cardiac function in CVB3 mice. RAA-CardAPs mice exerted immunomodulatory effects as evidenced by lower LV chemokines expression (C-C motif ligand [CCL]2 and CCL7), CD68+ cells presence, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, tumor necrosis factor-α, and IL-6 mRNA expression. In the chronic model, RAA-CardAPs reduced cardiac fibrosis and the severity of myocarditis, associated with an improvement in LV function. We conclude that RAA-CardAPs represent a treatment strategy to reduce the development of acute and chronic CVB3-induced myocarditis.

The still young and developing space age, characterized by lunar and Martian exploration and the vision of extraterrestrial settlements, presents a unique environment to study the impact of microgravity (µg) on human physiology and disease development. Cancer research is currently a key focus of international space science, as µg fundamentally impacts cellular processes like differentiation, adhesion, migration, proliferation, survival, cell death, or growth of cancer cells as well as the cytoskeleton and the extracellular matrix (ECM). By creating three-dimensional (3D) tumor models in a µg-environment, like multicellular spheroids (MCS), researchers can expedite drug discovery and development, reducing the need for animal testing. This concise review analyses the latest knowledge on the influence of µg on cancer cells and MCS formation. We will focus on cells from brain tumors, lung, breast, thyroid, prostate, gastrointestinal, and skin cancer exposed to real (r-) and simulated (s-) µg-conditions.

Regenerative therapies are currently lacking for spinal cord injury (SCI). Neural progenitor cells (NPCs) have emerged as a promising therapeutic approach. To facilitate translation of NPCs into the clinic, studying human NPCs in rodent models is required. The preclinical study of human NPCs in rodent models of SCI necessitates an optimal selection of immunomodulatory strategies, requiring a balance between modulating the immune system and preserving its functionality.

Given the high heterogeneity of type 2 diabetes mellitus (T2DM), it is imperative to develop personalized stem cell infusion regimen for targeted metabolic phenotype in order to ensure optimal therapeutic efficacy. In this study, we conducted a comparative analysis of 4 infusion regimens involving single and repeated infusions of human umbilical cord Wharton's jelly-derived MSCs (hucMSCs), single infusions of umbilical cord blood mononuclear cells (UCB), and sequential infusions of hucMSCs and UCB in T2DM rats. Results showed all 4 infusion regimens exhibited comparable efficacy in lowering fasting blood glucose levels and suppressing glucagon secretion. Single and double infusions of hucMSCs exhibited a tendency to migrate to the liver, thereby better at ameliorating hepatic glucose metabolism by enhancing glycogen synthesis and storage, promoting glycolysis, inhibiting gluconeogenesis, and improving insulin signal transduction. The sequential infusion of hucMSCs and UCB demonstrated specific cell tropism toward the pancreas, leading to prolonged glucose-lowering effects following a glucose tolerance test, restoration of early-phase insulin secretion, stimulation of islet beta cell proliferation and improvement in the beta/alpha ratio. Multiple injections, regardless of cell type, reduced the expression of systemic chronic inflammatory markers such as IL-1β, IL-6, IL-17, IL-22, and IFN-γ. Finally, a single dose of UCB exhibited a greater tendency to target visceral fat and enhanced effectiveness in regulating levels of total cholesterol and triglycerides. In conclusion, our study provided personalized stem cell regimens for diverse T2DM metabolic phenotypes, thereby offering improved treatment alternatives for future clinical trials and applications.

Endometriosis is a chronic inflammatory and neoangiogenic disease. Endostatin is one of the most effective inhibitors of angiogenesis. Mesenchymal stem cells (MSCs) have been investigated as compelling options for cell therapy. However, the effect and mechanism of action of endostatin-expressing endometrial MSCs (EMSCs) in endometriosis are unclear. Here, EMSCs were genetically modified to overexpress endostatin (EMSCs-Endo). A reduction in the angiogenic capacity of HUVECs was observed in vitro after treatment with EMSCs-Endo. EMSCs-Endo significantly suppressed endometriotic lesion growth in vivo. The limited efficacy was associated with suppressed angiogenesis. The miRNA-21-5p level and the levels of p-PI3K, p-mTOR, and p-Akt in HUVECs and mouse endometriotic lesions significantly decreased after treatment with EMSCs-Endo, whereas TIMP3 expression significantly increased. In summary, targeted gene therapy with EMSCs-Endo is feasible, and its efficacy in regulating endometriosis can be attributed to the inhibition of angiogenesis, suggesting that EMSCs could be used as promising vehicles for targeted gene therapy.

The use of dental implants to replace lost or damaged teeth has become increasingly widespread due to their reported high survival and success rates. In reality, the long-term survival of dental implants remains a health concern, based on their short-term predicted survival of ~15 years, significant potential for jawbone resorption, and risk of peri-implantitis. The ability to create functional bioengineered teeth, composed of living tissues with properties similar to those of natural teeth, would be a significant improvement over currently used synthetic titanium implants. To address this possibility, our research has focused on creating biological tooth substitutes. The study presented here validates a potentially clinically relevant bioengineered tooth replacement therapy for eventual use in humans. We created bioengineered tooth buds by seeding decellularized tooth bud (dTB) extracellular matrix (ECM) scaffolds with human dental pulp cells, porcine tooth bud-derived dental epithelial cells, and human umbilical vein endothelial cells. The resulting bioengineered tooth bud constructs were implanted in the mandibles of adult Yucatan minipigs and grown for 2 or 4 months. We observed the formation of tooth-like tissues, including tooth-supporting periodontal ligament tissues, in cell-seeded dTB ECM constructs. This preclinical translational study validates this approach as a potential clinically relevant alternative to currently used dental implants.

Acute myeloid leukemia (AML) is a devastating hematologic malignancy with high rates of relapse, which can, in part, be attributed to the dysregulation of chromatin modifications. These epigenetic modifications can affect the capacity of hematopoietic cells to self-renew or differentiate, which can lead to transformation. Aberrant histone modifications contribute to the derepression of self-renewal genes such as HOXA/B and MEIS1 in committed hematopoietic progenitors, which is considered a key mechanism of leukemogenesis in MLL-rearranged (MLL-r) and NPM1-mutated AML. As regulators of some of the key histone modifications in this disease, the menin-KMT2A and polycomb repressive (PRC1/2) complexes have been identified as promising targets for the treatment of AML. This review explores recent discoveries of how leukemic cells hijack these complexes and their interactions with other chromatin regulators to promote disease progression. We also discuss inhibitors targeting these complexes that have demonstrated therapeutic efficacy in preclinical and clinical studies and propose novel therapeutic combinations targeting the KMT2A and PRC1/2 broader interacting networks to overcome issues of resistance to existing monotherapies.

Epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) is responsible for the development of fibrotic cataracts, which contribute to severe visual impairment. Recent evidence has shown that mesenchymal stem cell-derived exosomes (MSC-Exo) can attenuate EMT in several tissues. However, the effect of MSC-Exo on EMT in LECs (LECs-EMT) has not been determined. In this study, we isolated exosomes from human umbilical cord MSCs (hucMSC-Exo) and evaluated their effect on LECs-EMT both in vitro and in vivo. HucMSC-Exo application significantly suppressed the expression of mesenchymal cell-associated genes while increasing the expression of epithelial cell-associated genes. Cell proliferation and migration of LECs undergoing EMT were inhibited after hucMSC-Exo treatment. The volume of EMT plaques in mice with injury-induced anterior subcapsular cataract (ASC) was significantly reduced in the hucMSC-Exo-treated group. Furthermore, miR-148a-3p was abundant in hucMSC-Exo. After transfection with miR-148a-3p inhibitor, the anti-fibrotic effect of hucMSC-Exo was attenuated in LECs-EMT. A dual-luciferase reporter assay identified PRNP as a direct target gene of miR-148a-3p. Furthermore, we verified that hucMSC-Exo inhibited LECs-EMT through the miR-148a-3p/PRNP axis and the potential downstream ERK signaling pathway. Taken together, our work reveals the inhibitory effect of hucMSC-Exo on LECs-EMT and the underlying mechanism involved, which may provide potential therapeutic options for fibrotic cataracts.

Background: In our previous study, we demonstrated that cartilage-derived stem cells (CDSCs) possess multi-differentiation potential, enabling direct bone-to-tendon structure regeneration after transplantation in a rat model. Therefore, the objective of this study is to investigate whether CDSCs are a suitable candidate for achieving biological regeneration of tendon injuries.

Methods: Tenogenic differentiation was evaluated through cell morphology observation, PCR, and Western blot (WB) analysis. Autophagic flux, transmission electron microscopy, and WB analysis were employed to elucidate the role of autophagy during CDSC tenogenic differentiation. Cell survival and tenogenesis of transplanted CDSCs were assessed using fluorescence detection of gross and frozen section images. Heterotopic ossification and quality of tendon healing were evaluated by immunofluorescence, hematoxylin-eosin (H&E), and Safrinin O/Fast Green stains.

Results: We found autophagy is activated in CDSCs when treated with cyclic tensile stress, which facilitates the preservation of their chondrogenic potential while impeding tenogenic differentiation. Inhibiting autophagy with chloroquine promoted tenogenic differentiation of CDSCs in response to cyclic tensile stress through activation of the Fgf2/Fgfr2 signaling pathway. This mechanism was further validated by 2 mouse transplantation models, revealed that autophagy inhibition could enhance the tendon regeneration efficacy of transplanted CDSCs at the patellar tendon resection site.

Conclusion: Our findings provide insights into CDSC transplantation for achieving biological regeneration of tendon injuries, and demonstrate how modulation of autophagy in CDSCs can promote tenogenic differentiation in response to tensile stress both in vivo and in vitro.

Mesenchymal stromal cells (MSCs) have been tested in multiple clinical trials to treat peripheral artery disease, especially the more severe form called critical limb ischemia. However, MSCs have often not met the expected efficacy endpoints. We developed a more potent therapeutic by genetically modifying MSCs to overexpress Vascular Endothelial Growth Factor (VEGF-A165). Here, we report preclinical studies submitted to the Food and Drug Administration (FDA) as part of our Investigational New Drug submission package. In vitro studies included the characterization of cell banks, transcriptome and secretome analysis, and in vitro potency assays. In vivo studies using immune-deficient NSG mice include dose-finding efficacy studies using a Matrigel plug model, cell retention studies, measurements of circulating VEGF, and toxicology studies to rule out severe adverse events. Our results suggest both the safety and efficacy of MSC/VEGF and support a first-in-human clinical trial to test this new combined cell/gene therapy.