Stem Cell Research & Therapy最新文献

Neurodegenerative diseases including Alzheimer's and Parkinson's disease are age-related disorders which severely impact quality of life and impose significant societal burdens. Cellular senescence is a critical factor in these disorders, contributing to their onset and progression by promoting permanent cell cycle arrest and reducing cellular function, affecting various types of cells in brain. Recent advancements in regenerative medicine have highlighted "R3" strategies-rejuvenation, regeneration, and replacement-as promising therapeutic approaches for neurodegeneration. This review aims to critically analyze the role of cellular senescence in neurodegenerative diseases and organizes therapeutic approaches within the R3 regenerative medicine paradigm. Specifically, we examine stem cell therapy, direct lineage reprogramming, and partial reprogramming in the context of R3, emphasizing how these interventions mitigate cellular senescence and counteracting aging-related neurodegeneration. Ultimately, this review seeks to provide insights into the complex interplay between cellular senescence and neurodegeneration while highlighting the promise of cell-based regenerative strategies to address these debilitating conditions.

Background: Photoreceptor (PR) enriched retinal organoid (RO) sheets (human embryonic stem cell [hESC]-derived ROs) resulted in restoration of visual acuity in immunocompromised retinal degenerate (RD) animal models after transplantation. Further assessment of their clinical potential requires evaluation in immunocompetent RD disease models with effective immune suppression. We characterized safety and efficacy profiles of both donor tissues and prospective immunosuppressive treatments in vitro; and in vivo in immunocompetent RD rats (strain SD-foxn1 Tg(S334ter)3Lav).

Methods: Retinal identity of ROs was validated by histology, flow cytometry and gene expression profiling, and their immunogenicity to sensitized human immune cells was measured by mixed lymphocyte reactions (MLR). We measured the effect of RO exposure for 1-4 weeks to therapeutic concentrations of our immunosuppressant drugs of choice on gene expression and metabolic function using quantitative PCR (qPCR) and functional and structural fluorescence lifetime imaging (FLIM), respectively. Immunocompetent RD graft recipients were immunosuppressed by implanted tacrolimus (TAC) pellets and mycophenolate mofetil (MMF) in food. In vivo, LCMS aided assessments of drug pharmacodynamics. Flow cytometry immunophenotyping and assay of post-surgery cytokines were used to assess and monitor drug efficacy. Retinal transplants were imaged in situ using optical coherence tomography (OCT) at defined time points post-surgery. Visual function was assessed by optokinetic tests (OKT) and superior colliculus electrophysiology recording. At study endpoints, immune cell infiltration and donor photoreceptor engraftment into host retinal architecture was evaluated by immunohistochemistry.

Results: Immunosuppressive drugs have no negative effects on RO development and metabolism in vitro; and low alloreactivity of ROs determined by MLR may be predictive to that of human graft recipients. In vivo, minimum effective dosing ranges of TAC and MMF were determined. We characterized the mechanisms and critical immune populations implicated in rejection; and subsequently demonstrated their effective suppression in our xenograft RD model. OKT measured significant visual improvement after RO transplantation. Transplants developed most retinal cell types including photoreceptors; and integrated with the host retina. However, immunosuppression induced higher sensitivity to ketamine anesthesia.

Conclusions: This study proves the concept that immunosuppression is likely tolerable in retinal transplantation and human stem cell therapy for retinal degeneration patients.

Background: Patients ineligible for lung transplant with end-stage Interstitial Lung Disease (ILD) on Extra-Corporeal Membrane Oxygenation (ECMO) face an appalling prognosis with limited therapeutic options. Due to the beneficial effect of Mesenchymal Stromal Cells (MSC) on inflammatory, immunological and infectious diseases, cell therapy has been proposed as an option, but administration is hampered by the ECMO.

Methods: Cryopreserved Wharton-jelly derived MSC (WJ-MSC) were conveniently diluted and directly applied consecutively on each lobule (5,1 ml = 10⁷ cells) at a continuous slow rate infused over one hour via flexible bronchoscopy (Consecutive IntraBronchial Administration method, CIBA method).

Results: Intrabronchial administration of MSC to a patient on ECMO was well tolerated by the patient even though it did not reverse the patient's ILD. This manuscript presents preliminary evidence from ongoing clinical trials program on Cell Therapy of Inflammatory, Immune and Infectious Diseases and, to our knowledge, is the first report of intrabronchial administration of MSC in a paediatric ECMO patient with ILD. Even more, MSC administered by this method do not reach the systemic circulation and do get blocked on ECMO membrane.

Conclusions: Direct intrabronchial administration of MSC in a patient on ECMO is feasible and safe, and may be a new avenue to be assayed in ECMO patients with inflammatory, immunological and infectious diseases of the lung.

Background: NF2-related Schwannomatosis (previously referred to as Neurofibromatosis Type 2, or NF2) is a genetic-associated disease resulting from mutations in the gene, NF2. NF2 encodes the Merlin protein, which acts as a tumor suppressor. Bilateral vestibular schwannoma (VS) is a hallmark of NF2. Although the exactly molecular mechanism mediating NF2-driven schwannomatosis is not fully understood, it is known that defective Merlin protein functionality leads to abnormal cell proliferation.

Methods: Herein, we utilized a human induced pluripotent stem cell (hiPSC)-based Schwann cell (SC) model to investigate the role of Merlin in human SCs. SCs were derived from hiPSCs carrying a NF2 mutation (c.191 T > C; p. L64P), its isogenic wild-type control cell line, and a NF2 patient-derived hiPSC line. Phenotypes were determined via immunocytochemistry and various bioassays. Different proteins interacting with Merlin in wild-type and NF2 mutation SCs were identified using co-immunoprecipitation followed by mass spectrometry.

Results: SC derived from NF2^L64P hiPSCs showed significantly higher proliferation and abnormal morphology compared to NF2^WT SCs. Phenotypes that could be restored by wildtype NF2 overexpression. Interactome profiling of Merlin (NF2) in SCs derived from NF2^WT- and NF2^L64P- hiPCSs identified differential protein binding levels. Among identified proteins, we validated the interaction among Merlin, an E3 ubiquitin ligase (Arkadia), and a SKI family co-repressor (SKOR2). This complex plays a significant role for this interaction in SC proliferation. Our findings were further validated by SCs derived from the patient-derived hiPSCs carrying a deletion in the chromosome 22 which spans the NF2 gene.

Conclusions: Our results presented a hiPSC-derived SC system for SC-related disease modeling and established a new model in which Merlin interacts with Arkadia and SKOR2. This interaction is required for the proper cell proliferation in human SCs.

Background: Osteoarthritis (OA) is a common and incurable disease in humans and animals. To gain a better understanding of the pathogenesis and identify potential treatments, miRNAs will be extracted and analysed from extracellular vesicles (EVs) of equine adipose derived mesenchymal stem cells (AdMSCs).

Methods: For this purpose we cultivated and pretreated AdMSCs under different conditions: interleukin 1β, shock wave, chondrogenic differentiation, chondrogenic differentiation under hypoxia, or after senescence. After treatment, EVs were harvested from the cell culture supernatants. Next-generation sequencing (NGS) was used to sequence the miRNAs from the EVs.

Results: A total of 89 miRNAs whose expression was significantly altered compared with that of an untreated negative control were identified. On average, 53 miRNAs were upregulated and 6 miRNAs were downregulated. Among others, the miRNAs eca-miR-101, eca-miR-143, eca-miR-145, eca-miR-146a, eca-miR-27a, eca-miR-29b, eca-miR-93, eca-miR-98, and eca-miR-221 were significantly increased after the stimulations, which, as known anti-inflammatory miRNAs, could be candidates for therapeutic use in the treatment of OA.

Conclusion: These results lay the foundation for further research into the significance and efficacy of these miRNAs so that this knowledge can be improved in further experiments and, ideally, translated into therapeutic use.

Background: Olfactory epithelial stem cells hold significant potential for treating olfactory dysfunction by facilitating tissue maintenance and repair. Understanding the inherent qualities of these stem cells is crucial for optimizing their therapeutic efficacy.

Methods: Olfactory epithelial samples were collected from patients with deviated nasal septum (DNS) and chronic rhinosinusitis (CRS). These were cultured to form olfactory neurospheres (ONS), which were then analyzed for neural stem cell markers, neurotrophic factor production, and their ability to differentiate into olfactory sensory neurons (OSNs). The regenerative efficacy of these ONS was tested in a methimazole-induced hyposmic mouse model, with the effects on cellular senescence, apoptosis, and proliferation in the olfactory epithelium assessed.

Results: Both DNS- and CRS-derived ONS exhibited neural stem cell characteristics. DNS-ONS displayed superior self-renewal capacity and higher neurotrophic factor production compared to CRS-ONS, which showed impaired OSN maturation and lower neurotrophic factor levels. In vivo, DNS-ONS were more effective in restoring olfaction, as evidenced by reduced cellular senescence, decreased apoptosis, and increased cell proliferation in the OE of methimazole-induced hyposmic mice.

Conclusions: These findings highlight the importance of selecting the appropriate ONS source for therapeutic applications, with DNS-ONS showing greater promise for olfactory epithelium repair and olfactory function restoration.

Recent studies have shown that mechanical properties such as extracellular matrix stiffness, fluid flow, weight loading, compression, and stretching can affect cellular functions. Some examples of cell responses to mechanical properties could be the migration of cancer cells from rigid to soft surfaces or the differentiation of fibroblasts into myofibroblasts. Cellular responses to mechanical changes can modify the insertion of proteins in the extracellular matrix (ECM), causing an increase in tissue stiffness with functional consequences. In general, mechanical and physical factors can affect any kind of cell phenotype in culture conditions and in vivo tissues. Cells sense mechanical stimuli by applying force and restructuring their shape and functions in response to the resistance of the stimuli. Furthermore, mechanical triggers can develop a "memory" for altering cellular plasticity and adaptation. This phenomenon is called cellular mechanical memory (CMM), a singular feature of mesenchymal stem cells (MSCs). Controlled targeting of CMM may resolve the scarcity of viable cells needed for cell based therapy (CBT) and implement studies concerning cancer research, fibrosis, and senescence. This review focusses on cells from the mesodermal lineage, such as MSCs, fibroblasts and chondrocytes, and the role of CMM as a potential target for CBT.

Background: Mesenchymal stem cell exosomes are the most extensively researched type of Extracellular vesicles (EVs) that offer novel avenues for hair regeneration. However, their use in the field of hair regeneration was limited by their poor production of exosomes. It has been discovered that intracellular vesicles (IVs), which are produced at a higher rate than exosomes, play a comparable biological purpose. As a result, we developed HTMI-MN, a microneedle that uses tremella, a type of Tremella polysaccharide (TPS), and hyaluronic acid (HA) as matrix materials. It has magnetic intracellular vesicles (Mag-IVs), which work in concert to treat androgenic alopecia (AGA) and encourage hair growth.

Methods: After characterization of the Mag-IVs, we evaluated the effect on angiogenesis by scratch assay, angiogenesis assay, Western Blot and ELISA assay. In addition, we tested the protective effect of Human hair papillary cells (HHDPCs) by CCK-8 method, Western Blot and flow cytometry. Finally, the effects of tremella polysaccharide on M1/M2 polarization of macrophages were detected by fluorescence staining, Western Blot and flow cytometry. AGA model was established in vivo by DHT, and treatment was given by microneedle injection.

Results: Our study found that Mag-IVs have greater power to promote angiogenesis and protect HHDPCs from apoptosis compared to other vesicles. Besides, tremella polysaccharide can make the transformation of macrophages to anti-inflammatory phenotype. Taken together, in vivo experiments showed that hair regeneration was faster in HTMI-MN-treated mice.

Conclusion: These results indicate that Mag-IVs and tremella polysaccharide can synergistically improve the hair microenvironment, which has a promising future for AGA treatment.

The search for an effective cell replacement therapy for diabetes has driven the development of "perfect" pancreatic islets from human pluripotent stem cells (hPSCs). These hPSC-derived pancreatic islet-like β cells can overcome the limitations for disease modelling, drug development and transplantation therapies in diabetes. Nevertheless, challenges remain in generating fully functional and mature β cells from hPSCs. This review underscores the significant efforts made by researchers to optimize various differentiation protocols aimed at enhancing the efficiency and quality of hPSC-derived pancreatic islets and proposes methods for their improvement. By emulating the natural developmental processes of pancreatic embryogenesis, specific growth factors, signaling molecules and culture conditions are employed to guide hPSCs towards the formation of mature β cells capable of secreting insulin in response to glucose. However, the efficiency of these protocols varies greatly among different human embryonic stem cell (hESC) and induced pluripotent stem cell (hiPSC) lines. This variability poses a particular challenge for generating patient-specific β cells. Despite recent advancements, the ultimate goal remains to develop a highly efficient directed differentiation protocol that is applicable across all genetic backgrounds of hPSCs. Although progress has been made, further research is required to optimize the protocols and characterization methods that could ensure the safety and efficacy of hPSC-derived pancreatic islets before they can be utilized in clinical settings.

Breast cancer remains the most frequently diagnosed cancer globally, exerting a profound impact on women's health and healthcare systems. Central to its pathogenesis and therapeutic resistance are breast cancer stem cells (BCSCs), which possess unique properties such as self-renewal, differentiation, and resistance to conventional therapies, contributing to tumor initiation, metastasis, and recurrence. This comprehensive review elucidates the pivotal role of the mechanistic target of rapamycin (mTOR) pathway in regulating BCSCs and its implications for breast cancer progression and treatment resistance. We explore the cellular mechanisms by which mTOR influences metastasis, metabolism, autophagy, and ferroptosis in BCSCs, highlighting its contribution to epithelial-to-mesenchymal transition (EMT), metabolic reprogramming, and survival under therapeutic stress. On a molecular level, mTOR interacts with key signaling pathways including PI3K/Akt, Notch, IGF-1R, AMPK, and TGF-β, as well as regulatory proteins and non-coding RNAs, orchestrating a complex network that sustains BCSC properties and mediates chemoresistance and radioresistance. The review further examines various therapeutic strategies targeting the mTOR pathway in BCSCs, encompassing selective PI3K/Akt/mTOR inhibitors, monoclonal antibodies, natural products, and innovative approaches such as nanoparticle-mediated drug delivery. Clinical trials investigating mTOR inhibitors like sirolimus and combination therapies with agents such as everolimus and trastuzumab are discussed, underscoring their potential in eradicating BCSCs and improving patient outcomes. Additionally, natural compounds and repurposed drugs offer promising adjunctive therapies by modulating mTOR activity and targeting BCSC-specific vulnerabilities. In conclusion, targeting the mTOR pathway presents a viable and promising avenue for enhancing breast cancer treatment efficacy by effectively eliminating BCSCs, reducing tumor recurrence, and improving overall patient survival. Continued research and clinical validation of mTOR-targeted therapies are essential to translate these insights into effective clinical interventions, ultimately advancing personalized cancer management and therapeutic outcomes for breast cancer patients.