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A key goal of evolutionary genomics is to harness molecular data to draw inferences about selective forces that have acted on genomes. The field progresses in large part through the development of advanced molecular-evolution analysis methods. Here we explored the intersection between classical sequence-based tests for selection and an empirical expression-based approach, using stem cells from Mus musculus subspecies as a model. Using a test of directional, cis-regulatory evolution across genes in pathways, we discovered a unique program of induction of translation genes in stem cells of the Southeast Asian mouse M. m. castaneus relative to its sister taxa. We then mined population-genomic sequences to pursue underlying regulatory mechanisms for this expression divergence, finding robust evidence for alleles unique to M. m. castaneus at the upstream regions of the translation genes. We interpret our data under a model of changes in lineage-specific pressures across Mus musculus in stem cells with high translational capacity. Our findings underscore the rigor of integrating expression and sequence-based methods to generate hypotheses about evolutionary events from long ago.

Tumors can induce systemic disturbances in distant organs, leading to physiological changes that enhance host morbidity. In Drosophila cancer models, tumors have been known for decades to cause hypervolemic "bloating" of the abdominal cavity. Here we use allograft and transgenic tumors to show that hosts display fluid retention associated with autonomously defective secretory capacity of fly renal tubules, which function analogous to those of the human kidney. Excretion from these organs is blocked by abnormal cells that originate from inappropriate activation of normally quiescent renal stem cells (RSCs). Blockage is initiated by IL-6-like oncokines that perturb renal water-transporting cells and trigger a damage response in RSCs that proceeds pathologically. Thus, a chronic inflammatory state produced by the tumor causes paraneoplastic fluid dysregulation by altering cellular homeostasis of host renal units.

Wildlife biodiversity is essential for healthy, resilient and sustainable ecosystems. For biologists, this diversity also represents a treasure trove of genetic, molecular and developmental mechanisms that deepen our understanding of the origins and rules of life. However, the rapid decline in biodiversity reported recently foreshadows a potentially catastrophic collapse of many important ecosystems and the associated irreversible loss of many forms of life on our planet. Immediate action by conservationists of all stripes is required to avert this disaster. In this Spotlight, we draw together insights and proposals discussed at a recent workshop hosted by Revive & Restore, which gathered experts to discuss how stem cell technologies can support traditional conservation techniques and help protect animal biodiversity. We discuss reprogramming, in vitro gametogenesis, disease modelling and embryo modelling, and we highlight the prospects for leveraging stem cell technologies beyond mammalian species.

We previously showed that inhibition of glycolysis in cutaneous squamous cell carcinoma (SCC)-initiating cells had no effect on tumorigenesis, despite the perceived requirement of the Warburg effect, which was thought to drive carcinogenesis. Instead, these SCCs were metabolically flexible and sustained growth through glutaminolysis, another metabolic process frequently implicated to fuel tumorigenesis in various cancers. Here, we focused on glutaminolysis and genetically blocked this process through glutaminase (GLS) deletion in SCC cells of origin. Genetic deletion of GLS had little effect on tumorigenesis due to the up-regulated lactate consumption and utilization for the TCA cycle, providing further evidence of metabolic flexibility. We went on to show that posttranscriptional regulation of nutrient transporters appears to mediate metabolic flexibility in this SCC model. To define the limits of this flexibility, we genetically blocked both glycolysis and glutaminolysis simultaneously and found the abrogation of both of these carbon utilization pathways was enough to prevent both papilloma and frank carcinoma.

The role of mitochondria in neurodegenerative diseases is crucial, and recent developments have highlighted its significance in cell therapy. Mitochondrial dysfunction has been implicated in various neurodegenerative disorders, including Alzheimers, Parkinsons, amyotrophic lateral sclerosis, and Huntingtons diseases. Understanding the impact of mitochondrial biology on these conditions can provide valuable insights for developing targeted cell therapies. This mini-review refocuses on mitochondria and emphasizes the potential of therapies leveraging mesenchymal stem cells, embryonic stem cells, induced pluripotent stem cells, stem cell-derived secretions, and extracellular vesicles. Mesenchymal stem cell-mediated mitochondria transfer is highlighted for restoring mitochondrial health in cells with dysfunctional mitochondria. Additionally, attention is paid to gene-editing techniques such as mito-CRISPR, mitoTALENs, mito-ZNFs, and DdCBEs to ensure the safety and efficacy of stem cell treatments. Challenges and future directions are also discussed, including the possible tumorigenic effects of stem cells, off-target effects, disease targeting, immune rejection, and ethical issues.

Our understanding of the transitions of human embryonic stem cells (hESCs) between distinct stages of pluripotency relies predominantly on regulation by transcriptional and epigenetic programs with limited insight on the role of established morphological changes. We report remodeling of the actin cytoskeleton of hESCs as they transition from primed to naïve pluripotency which includes assembly of a ring of contractile actin filaments encapsulating colonies of naïve hESCs. Activity of the Arp2/3 complex is required for formation of the actin ring, to establish uniform cell mechanics within naïve colonies, to promote nuclear translocation of the Hippo pathway effectors YAP and TAZ, and for effective transition to naïve pluripotency. RNA-sequencing analysis confirms that Arp2/3 complex activity regulates Hippo signaling in hESCs, and impaired naïve pluripotency with inhibited Arp2/3 complex activity is rescued by expressing a constitutively active, nuclear-localized YAP-S127A. Moreover, expression of YAP-S127A partially restores the actin filament fence with Arp2/3 complex inhibition, suggesting that actin filament remodeling is both upstream and downstream of YAP activity. These new findings on the cell biology of hESCs reveal a mechanism for cytoskeletal dynamics coordinating cell mechanics to regulate gene expression and facilitate transitions between pluripotency states.

In lactating mothers, the high calcium (Ca2+) demand for milk production triggers significant bone loss1. Although oestrogen normally counteracts excessive bone resorption by promoting bone formation, this sex steroid drops precipitously during this postpartum period. Here we report that brain-derived cellular communication network factor 3 (CCN3) secreted from KISS1 neurons of the arcuate nucleus (ARCKISS1) fills this void and functions as a potent osteoanabolic factor to build bone in lactating females. We began by showing that our previously reported female-specific, dense bone phenotype2 originates from a humoral factor that promotes bone mass and acts on skeletal stem cells to increase their frequency and osteochondrogenic potential. This circulatory factor was then identified as CCN3, a brain-derived hormone from ARCKISS1 neurons that is able to stimulate mouse and human skeletal stem cell activity, increase bone remodelling and accelerate fracture repair in young and old mice of both sexes. The role of CCN3 in normal female physiology was revealed after detecting a burst of CCN3 expression in ARCKISS1 neurons coincident with lactation. After reducing CCN3 in ARCKISS1 neurons, lactating mothers lost bone and failed to sustain their progeny when challenged with a low-calcium diet. Our findings establish CCN3 as a potentially new therapeutic osteoanabolic hormone for both sexes and define a new maternal brain hormone for ensuring species survival in mammals.

Although microglia are macrophages of the central nervous system, their involvement is not limited to immune functions. The roles of microglia during development in humans remain poorly understood due to limited access to fetal tissue. To understand how microglia can impact human neurodevelopment, the methyl-CpG binding protein 2 (MECP2) gene was knocked out in human microglia-like cells (MGLs). Disruption of the MECP2 in MGLs led to transcriptional and functional perturbations, including impaired phagocytosis. The co-culture of healthy MGLs with MECP2-knockout (KO) neurons rescued synaptogenesis defects, suggesting a microglial role in synapse formation. A targeted drug screening identified ADH-503, a CD11b agonist, restored phagocytosis and synapse formation in spheroid-MGL co-cultures, significantly improved disease progression, and increased survival in MeCP2-null mice. These results unveil a MECP2-specific regulation of human microglial phagocytosis and identify a novel therapeutic treatment for MECP2-related conditions.

Photoreceptor degeneration is a major cause of untreatable blindness worldwide and has recently been targeted by emerging technologies, including cell- and gene-based therapies. Cell types of neural lineage have shown promise for replacing either photoreceptors or retinal pigment epithelial cells following delivery to the subretinal space, while cells of bone marrow lineage have been tested for retinal trophic effects following delivery to the vitreous cavity. Here we explore an alternate approach in which cells from the immature neural retinal are delivered to the vitreous cavity with the goal of providing trophic support for degenerating photoreceptors. Rat and human retinal progenitor cells were transplanted to the vitreous of rats with a well-studied photoreceptor dystrophy, resulting in substantial anatomical preservation and functional rescue of vision. This work provides scientific proof-of-principle for a novel therapeutic approach to photoreceptor degeneration that is currently being evaluated in clinical trials.

Fibroblasts are present throughout the body and function to maintain tissue homeostasis. Recent studies have identified diverse fibroblast subsets in healthy and injured tissues1,2, but the origins and functional roles of injury-induced fibroblast lineages remain unclear. Here we show that lung-specialized alveolar fibroblasts take on multiple molecular states with distinct roles in facilitating responses to fibrotic lung injury. We generate a genetic tool that uniquely targets alveolar fibroblasts to demonstrate their role in providing niches for alveolar stem cells in homeostasis and show that loss of this niche leads to exaggerated responses to acute lung injury. Lineage tracing identifies alveolar fibroblasts as the dominant origin for multiple emergent fibroblast subsets sequentially driven by inflammatory and pro-fibrotic signals after injury. We identify similar, but not completely identical, fibroblast lineages in human pulmonary fibrosis. TGFβ negatively regulates an inflammatory fibroblast subset that emerges early after injury and stimulates the differentiation into fibrotic fibroblasts to elicit intra-alveolar fibrosis. Blocking the induction of fibrotic fibroblasts in the alveolar fibroblast lineage abrogates fibrosis but exacerbates lung inflammation. These results demonstrate the multifaceted roles of the alveolar fibroblast lineage in maintaining normal alveolar homeostasis and orchestrating sequential responses to lung injury.

In vitro gametogenesis (IVG), the reconstitution of germ cell development in vitro, is an emerging stem cell-based technology with profound implications for reproductive science. Despite researchers' long-term goals for future clinical applications, little is currently known about the views of IVG held by the stakeholders potentially most affected by its introduction in humans. We conducted focus groups and interviews with 80 individuals with lived experience of infertility and/or LGBTQ+ family formation in the US, two intersecting groups of potential IVG users. Respondents expressed hope that IVG would lead to higher reproductive success than current assisted reproductive technology (ART), alleviate suffering associated with ART use, and promote greater social inclusion, while expressing concerns predominantly framed in terms of equity and safety. These findings underscore the importance of sustained engagement with stakeholders with relevant experience to anticipate the implications of IVG for research and clinical translation.

Tissue regeneration after damage is generally thought to involve the mobilization of adult stem cells that divide and differentiate into progressively specialized progeny. However, recent studies indicate that tissue regeneration can be accompanied by reversion to a fetal-like state. During this process, cells at the injury site reactivate programs that operate during fetal development but are typically absent in adult homeostasis. Here, we summarize our current understanding of the molecular signals and epigenetic mediators that orchestrate "fetal-like reversion" during intestinal regeneration. We also explore evidence for this phenomenon in other organs and species and highlight open questions that merit future examination.

Aging coincides with the progressive loss of muscle mass and strength, increased adiposity, and diminished physical function. Accordingly, interventions aimed at improving muscle, metabolic, and/or physical health are of interest to mitigate the adverse effects of aging. In this study, we tested a stem cell secretome product, which contains extracellular vesicles and growth, cytoskeletal remodeling, and immunomodulatory factors. We examined the effects of 4 weeks of 2×/week unilateral intramuscular secretome injections (quadriceps) in ambulatory aged male C57BL/6 mice (22-24 months) compared to saline-injected aged-matched controls. Secretome delivery substantially increased whole-body lean mass and decreased fat mass, corresponding to higher myofiber cross-sectional area and smaller adipocyte size, respectively. Secretome-treated mice also had greater whole-body physical function (grip strength and rotarod performance) and had higher energy expenditure and physical activity levels compared to control mice. Furthermore, secretome-treated mice had greater skeletal muscle Pax7+ cell abundance, capillary density, collagen IV turnover, reduced intramuscular lipids, and greater Akt and hormone sensitive lipase phosphorylation in adipose tissue. Finally, secretome treatment in vitro directly enhanced muscle cell growth and IL-6 production, and in adipocytes, it reduced lipid content and improved insulin sensitivity. Moreover, indirect treatment with secretome-treated myotube culture media also enhanced muscle cell growth and adipocyte size reduction. Together, these data suggest that intramuscular treatment with a stem cell secretome improves whole-body metabolism, physical function, and remodels skeletal muscle and adipose tissue in aged mice.

Dorsal interneurons (dIs) in the spinal cord encode the perception of touch, pain, heat, itchiness and proprioception. Previous studies using genetic strategies in animal models have revealed important insights into dI development, but the molecular details of how dIs arise as distinct populations of neurons remain incomplete. We have developed a resource to investigate dI fate specification by combining a single-cell RNA-Seq atlas of mouse embryonic stem cell-derived dIs with pseudotime analyses. To validate this in silico resource as a useful tool, we used it to first identify genes that are candidates for directing the transition states that lead to distinct dI lineage trajectories, and then validated them using in situ hybridization analyses in the developing mouse spinal cord in vivo. We have also identified an endpoint of the dI5 lineage trajectory and found that dIs become more transcriptionally homogeneous during terminal differentiation. This study introduces a valuable tool for further discovery about the timing of gene expression during dI differentiation and demonstrates its utility in clarifying dI lineage relationships.

Neural stem cells (NSCs) are multipotent and correct fate determination is crucial to guarantee brain formation and homeostasis. How NSCs are instructed to generate neuronal or glial progeny is not well understood. Here, we addressed how murine adult hippocampal NSC fate is regulated and described how scaffold attachment factor B (SAFB) blocks oligodendrocyte production to enable neuron generation. We found that SAFB prevents NSC expression of the transcription factor nuclear factor I/B (NFIB) by binding to sequences in the Nfib mRNA and enhancing Drosha-dependent cleavage of the transcripts. We show that increasing SAFB expression prevents oligodendrocyte production by multipotent adult NSCs, and conditional deletion of Safb increases NFIB expression and oligodendrocyte formation in the adult hippocampus. Our results provide novel insights into a mechanism that controls Drosha functions for selective regulation of NSC fate by modulating the post-transcriptional destabilization of Nfib mRNA in a lineage-specific manner.

Working in a stem cell laboratory necessitates a thorough understanding of complex cell culture protocols, the operation of sensitive scientific equipment, adherence to safety standards, and general laboratory etiquette. For novice student researchers, acquiring the necessary specialized knowledge before their initial laboratory experience can be a formidable task. Similarly, for experienced laboratory personnel, efficiently and uniformly training new trainees to a rigorous standard presents a significant challenge. In response to these issues, we have developed an educational and interactive virtual cell culture environment. This interactive virtual lab aims to equip students with foundational knowledge in maintaining cortical brain organoids and to instill an understanding of pertinent safety procedures and laboratory etiquette. The gamification of this training process seeks to provide laboratory supervisors in highly specialized fields with an effective tool to integrate students into their work environments more rapidly and safely.

Trophoblast stem cells (TSCs) are a proliferative multipotent population derived from the trophectoderm of the blastocyst, which will give rise to all the functional cell types of the trophoblast compartment of the placenta. The isolation and culture of TSCs in vitro represent a robust model to study mechanisms of trophoblast differentiation into mature cells both in successful and diseased pregnancy. Despite the highly conserved functions of the placenta, there is extreme variability in placental morphology, fetal-maternal interface, and development among eutherian mammals. This review aims to summarize the establishment and maintenance of TSCs in mammals such as primates, including human, rodents, and nontraditional animal models with a primary emphasis on epigenetic regulation of their origin while defining gaps in the current literature and areas of further development. FGF signaling is critical for mouse TSCs but dispensable for derivation of TSCs in other species. Human, simian, and bovine TSCs have much more complicated requirements of signaling pathways including activation of WNT and inhibition of TGFβ cascades. Epigenetic features such as DNA and histone methylation as well as histone acetylation are dynamic during development and are expressed in cell- and gestational age-specific pattern in placental trophoblasts. While TSCs from different species seem to recapitulate some select epigenomic features, there is a limitation in the comprehensive understanding of TSCs and how well TSCs retain placental epigenetic marks. Therefore, future studies should be directed at investigating epigenomic features of global and placental-specific gene expression in primary trophoblasts and TSCs.

Spermatogonial stem cells functionality reside in the slow-cycling and heterogeneous undifferentiated spermatogonia cell population. This pool of cells supports lifelong fertility in adult males by balancing self-renewal and differentiation to produce haploid gametes. However, the molecular mechanisms underpinning long-term stemness of undifferentiated spermatogonia during adulthood remain unclear. Here, we discover that an epigenetic regulator, Polycomb repressive complex 1 (PRC1), shields adult undifferentiated spermatogonia from differentiation, maintains slow cycling, and directs commitment to differentiation during steady-state spermatogenesis in adults. We show that PRC2-mediated H3K27me3 is an epigenetic hallmark of adult undifferentiated spermatogonia. Indeed, spermatogonial differentiation is accompanied by a global loss of H3K27me3. Disruption of PRC1 impairs global H3K27me3 deposition, leading to precocious spermatogonial differentiation. Therefore, PRC1 directs PRC2-H3K27me3 deposition to maintain the self-renewing state of undifferentiated spermatogonia. Importantly, in contrast to its role in other tissue stem cells, PRC1 negatively regulates the cell cycle to maintain slow cycling of undifferentiated spermatogonia. Our findings have implications for how epigenetic regulators can be tuned to regulate the stem cell potential, cell cycle and differentiation to ensure lifelong fertility in adult males.

Peripheral artery disease is an atherosclerotic disease associated with limb ischemia that necessitates limb amputation in severe cases. Cell therapies comprised of adult mononuclear or stromal cells have been clinically tested and show moderate benefits. Bioengineering strategies can be applied to modify cell behavior and function in a controllable fashion. Using mechanically tunable or spatially controllable biomaterials, we highlight examples in which biomaterials can increase the survival and function of the transplanted cells to improve their revascularization efficacy in preclinical models. Biomaterials can be used in conjunction with soluble factors or genetic approaches to further modulate the behavior of transplanted cells and the locally implanted tissue environment in vivo. We critically assess the advances in bioengineering strategies such as 3-dimensional bioprinting and immunomodulatory biomaterials that can be applied to the treatment of peripheral artery disease and then discuss the current challenges and future directions in the implementation of bioengineering strategies.

Individuals with Williams syndrome (WS), a neurodevelopmental disorder caused by hemizygous loss of 26-28 genes at 7q11.23, characteristically portray a hypersocial phenotype. Copy-number variations and mutations in one of these genes, GTF2I, are associated with altered sociality and are proposed to underlie hypersociality in WS. However, the contribution of GTF2I to human neurodevelopment remains poorly understood. Here, human cellular models of neurodevelopment, including neural progenitors, neurons, and three-dimensional cortical organoids, are differentiated from CRISPR-Cas9-edited GTF2I-knockout (GTF2I-KO) pluripotent stem cells to investigate the role of GTF2I in human neurodevelopment. GTF2I-KO progenitors exhibit increased proliferation and cell-cycle alterations. Cortical organoids and neurons demonstrate increased cell death and synaptic dysregulation, including synaptic structural dysfunction and decreased electrophysiological activity on a multielectrode array. Our findings suggest that changes in synaptic circuit integrity may be a prominent mediator of the link between alterations in GTF2I and variation in the phenotypic expression of human sociality.

Human pluripotent stem cell-derived neural progenitor cells (NPCs) are an essential tool for the study of brain development and developmental disorders such as autism. Here, we present a protocol to generate NPCs rapidly and reproducibly from human stem cells using dual-SMAD inhibition coupled with a brief pulse of mouse neurogenin-2 (Ngn2) overexpression. We detail the 48-h induction scheme deployed to produce these cells-termed stem cell-derived Ngn2-accelerated progenitor cells-followed by steps for expansion, purification, banking, and quality assessment. For complete details on the use and execution of this protocol, please refer to Wells et al.1.

The fetal brain of the mouse is thought to be dependent upon the placenta as a source of serotonin (5-hydroxytryptamine; 5-HT) and other factors. How factors reach the developing brain remains uncertain but are postulated here to be part of the cargo carried by placental extracellular vesicles (EV). We have analyzed the protein, catecholamine, and small RNA content of EV from mouse trophoblast stem cells (TSC) and TSC differentiated into parietal trophoblast giant cells (pTGC), potential primary purveyors of 5-HT. Current studies examined how exposure of mouse neural progenitor cells (NPC) to EV from either TSC or pTGC affect their transcriptome profiles. The EV from trophoblast cells contained relatively high amounts of 5-HT, as well as dopamine and norepinephrine, but there were no significant differences between EV derived from pTGC and from TSC. Content of miRNA and small nucleolar (sno)RNA, however, did differ according to EV source, and snoRNA were upregulated in EV from pTGC. The primary inferred targets of the microRNA (miRNA) from both pTGC and TSC were mRNA enriched in the fetal brain. NPC readily internalized EV, leading to changes in their transcriptome profiles. Transcripts regulated were mainly ones enriched in neural tissues. The transcripts in EV-treated NPC that demonstrated a likely complementarity with miRNA in EV were mainly up- rather than downregulated, with functions linked to neuronal processes. Our results are consistent with placenta-derived EV providing direct support for fetal brain development and being an integral part of the placenta-brain axis.

In single-cell RNA sequencing (scRNA-Seq), gene expression is assessed individually for each cell, allowing the investigation of developmental processes, such as embryogenesis and cellular differentiation and regeneration, at unprecedented resolution. In such dynamic biological systems, cellular states form a continuum, e.g., for the differentiation of stem cells into mature cell types. This process is often represented via a trajectory in a reduced-dimensional representation of the scRNA-Seq dataset. While many methods have been suggested for trajectory inference, it is often unclear how to handle multiple biological groups or conditions, e.g., inferring and comparing the differentiation trajectories of wild-type and knock-out stem cell populations. In this manuscript, we present condiments, a method for the inference and downstream interpretation of cell trajectories across multiple conditions. Our framework allows the interpretation of differences between conditions at the trajectory, cell population, and gene expression levels. We start by integrating datasets from multiple conditions into a single trajectory. By comparing the cells conditions along the trajectorys path, we can detect large-scale changes, indicative of differential progression or fate selection. We also demonstrate how to detect subtler changes by finding genes that exhibit different behaviors between these conditions along a differentiation path.

The Murphy Roths Large (MRL) mouse strain has super-healing properties that enhance recovery from injury. In mice, the DBA/2J strain intensifies many aspects of muscular dystrophy, so we evaluated the ability of the MRL strain to suppress muscular dystrophy in the Sgcg-null mouse model of limb girdle muscular dystrophy. A comparative analysis of Sgcg-null mice in the DBA/2J versus MRL strains showed greater myofiber regeneration, with reduced structural degradation of muscle in the MRL strain. Transcriptomic profiling of dystrophic muscle indicated strain-dependent expression of extracellular matrix (ECM) and TGF-β signaling genes. To investigate the MRL ECM, cellular components were removed from dystrophic muscle sections to generate decellularized myoscaffolds. Decellularized myoscaffolds from dystrophic mice in the protective MRL strain had significantly less deposition of collagen and matrix-bound TGF-β1 and TGF-β3 throughout the matrix. Dystrophic myoscaffolds from the MRL background, but not the DBA/2J background, were enriched in myokines like IGF-1 and IL-6. C2C12 myoblasts seeded onto decellularized matrices from Sgcg-/- MRL and Sgcg-/- DBA/2J muscles showed the MRL background induced greater myoblast differentiation compared with dystrophic DBA/2J myoscaffolds. Thus, the MRL background imparts its effect through a highly regenerative ECM, which is active even in muscular dystrophy.

Hair follicle stem cells (HFSCs) and dermal papilla cells (DPCs) are crucial in the biogenesis and maintenance of hair follicles (HFs). This study demonstrated that a fragment derived from aminoacyl-tRNA synthetase-interacting multifunctional protein1 (AIMP1) secreted from HFSCs activated DPCs and maintained HF homeostasis. A histological analysis revealed that AIMP1 levels in HF decreased with hair loss. Hair regrowth in AIMP1-induced mice was faster than in non-induced mice. Deletion mapping revealed 41 amino acids (TN41, aa 6-46) as the active region of AIMP1. The N-terminal peptide fragment of AIMP1 generated by MMP1 was secreted from Wnt-treated HFSCs to activate DPCs. TN41 activated Akt and ERK, increased β-catenin, and enhanced DPC activation. TN41 promoted hair shaft elongation in cultured human HFs and improved the hair-inducing activity of cultured DPC spheroids. Our findings suggest that the AIMP1 fragment secreted from HFSCs stimulates active hair regrowth through activating DPCs.

Vascular cells self-organize into unique structures guided by cell proliferation, migration, and/or differentiation from neighboring cells, mechanical factors, and/or soluble signals. However, the relative contribution of each of these factors remains unclear. Our objective was to develop a computational model to explore the different factors affecting the emerging micropatterns in 2D. This was accomplished by developing a stochastic on-lattice population-based model starting with vascular progenitor cells with the potential to proliferate, migrate, and/or differentiate into either endothelial cells or smooth muscle cells. The simulation results yielded patterns that were qualitatively and quantitatively consistent with experimental observations. Our results suggested that post-differentiation cell migration and proliferation when balanced could generate between 30-70% of each cell type enabling the formation of vascular patterns. Moreover, the cell-to-cell sensing could enhance the robustness of this patterning. These findings computationally supported that 2D patterning is mechanistically similar to current microfluidic platforms that take advantage of the migration-directed self-assembly of mature endothelial and mural cells to generate perfusable 3D vasculature in permissible hydrogel environments and suggest that stem or progenitor cells may not be fully necessary components in many tissue formations like those formed by vasculogenesis.

LMNA-related dilated cardiomyopathy (DCM) is an autosomal-dominant genetic condition with cardiomyocyte and conduction system dysfunction often resulting in heart failure or sudden death. The condition is caused by mutation in the Lamin A/C (LMNA) gene encoding Type-A nuclear lamin proteins involved in nuclear integrity, epigenetic regulation of gene expression, and differentiation. The molecular mechanisms of the disease are not completely understood, and there are no definitive treatments to reverse progression or prevent mortality. We investigated possible mechanisms of LMNA-related DCM using induced pluripotent stem cells derived from a family with a heterozygous LMNA c.357-2A>G splice-site mutation. We differentiated one LMNA-mutant iPSC line derived from an affected female (Patient) and two non-mutant iPSC lines derived from her unaffected sister (Control) and conducted single-cell RNA sequencing for 12 samples (four from Patients and eight from Controls) across seven time points: Day 0, 2, 4, 9, 16, 19, and 30. Our bioinformatics workflow identified 125,554 cells in raw data and 110,521 (88%) high-quality cells in sequentially processed data. Unsupervised clustering, cell annotation, and trajectory inference found complex heterogeneity: ten main cell types; many possible subtypes; and lineage bifurcation for cardiac progenitors to cardiomyocytes (CMs) and epicardium-derived cells (EPDCs). Data integration and comparative analyses of Patient and Control cells found cell type and lineage-specific differentially expressed genes (DEGs) with enrichment, supporting pathway dysregulation. Top DEGs and enriched pathways included 10 ZNF genes and RNA polymerase II transcription in pluripotent cells (PP); BMP4 and TGF Beta/BMP signaling, sarcomere gene subsets and cardiogenesis, CDH2 and EMT in CMs; LMNA and epigenetic regulation, as well as DDIT4 and mTORC1 signaling in EPDCs. Top DEGs also included XIST and other X-linked genes, six imprinted genes (SNRPN, PWAR6, NDN, PEG10, MEG3, MEG8), and enriched gene sets related to metabolism, proliferation, and homeostasis. We confirmed Lamin A/C haploinsufficiency by allelic expression and Western blot. Our complex Patient-derived iPSC model for Lamin A/C haploinsufficiency in PP, CM, and EPDC provided support for dysregulation of genes and pathways, many previously associated with Lamin A/C defects, such as epigenetic gene expression, signaling, and differentiation. Our findings support disruption of epigenomic developmental programs, as proposed in other LMNA disease models. We recognized other factors influencing epigenetics and differentiation; thus, our approach needs improvement to further investigate this mechanism in an iPSC-derived model.

Retinitis pigmentosa (RP), a heterogenous group of inherited retinal disorder, causes slow progressive vision loss with no effective treatments available. Mutations in the rhodopsin gene (RHO) account for ~25% cases of autosomal dominant RP (adRP). In this study, we describe the disease characteristics of the first-ever reported mono-allelic copy number variation (CNV) in RHO as a novel cause of adRP. We (a) show advanced retinal degeneration in a male patient (68 years of age) harboring four transcriptionally active intact copies of rhodopsin, (b) recapitulated the clinical phenotypes using retinal organoids, and (c) assessed the utilization of a small molecule, Photoregulin3 (PR3), as a clinically viable strategy to target and modify disease progression in RP patients associated with RHO-CNV. Patient retinal organoids showed photoreceptors dysgenesis, with rod photoreceptors displaying stunted outer segments with occasional elongated cilia-like projections (microscopy); increased RHO mRNA expression (quantitative real-time PCR [qRT-PCR] and bulk RNA sequencing); and elevated levels and mislocalization of rhodopsin protein (RHO) within the cell body of rod photoreceptors (western blotting and immunohistochemistry) over the extended (300 days) culture time period when compared against control organoids. Lastly, we utilized PR3 to target NR2E3, an upstream regulator of RHO, to alter RHO expression and observed a partial rescue of RHO protein localization from the cell body to the inner/outer segments of rod photoreceptors in patient organoids. These results provide a proof-of-principle for personalized medicine and suggest that RHO expression requires precise control. Taken together, this study supports the clinical data indicating that RHO-CNV associated adRPdevelops as a result of protein overexpression, thereby overloading the photoreceptor post-translational modification machinery.

Metabolism participates in the control of stem cell function and subsequent maintenance of tissue homeostasis. How this is achieved in the context of adult stem cell niches in coordination with other local and intrinsic signaling cues is not completely understood. The Target of Rapamycin (TOR) pathway is a master regulator of metabolism and plays essential roles in stem cell maintenance and differentiation. In the Drosophila male germline, mTORC1 is active in germline stem cells (GSCs) and early germ cells. Targeted RNAi-mediated downregulation of mTor in early germ cells causes a block and/or a delay in differentiation, resulting in an accumulation of germ cells with GSC-like features. These early germ cells also contain unusually large and dysfunctional autolysosomes. In addition, downregulation of mTor in adult male GSCs and early germ cells causes non-autonomous activation of mTORC1 in neighboring cyst cells, which correlates with a disruption in the coordination of germline and somatic differentiation. Our study identifies a previously uncharacterized role of the TOR pathway in regulating male germline differentiation.

Over the past two decades Biomedical Engineering has emerged as a major discipline that bridges societal needs of human health care with the development of novel technologies. Every medical institution is now equipped at varying degrees of sophistication with the ability to monitor human health in both non-invasive and invasive modes. The multiple scales at which human physiology can be interrogated provide a profound perspective on health and disease. We are at the nexus of creating avatars (herein defined as an extension of digital twins) of human patho/physiology to serve as paradigms for interrogation and potential intervention. Motivated by the emergence of these new capabilities, the IEEE Engineering in Medicine and Biology Society, the Departments of Biomedical Engineering at Johns Hopkins University and Bioengineering at University of California at San Diego sponsored an interdisciplinary workshop to define the grand challenges that face biomedical engineering and the mechanisms to address these challenges. The Workshop identified five grand challenges with cross-cutting themes and provided a roadmap for new technologies, identified new training needs, and defined the types of interdisciplinary teams needed for addressing these challenges. The themes presented in this paper include: 1) accumedicine through creation of avatars of cells, tissues, organs and whole human; 2) development of smart and responsive devices for human function augmentation; 3) exocortical technologies to understand brain function and treat neuropathologies; 4) the development of approaches to harness the human immune system for health and wellness; and 5) new strategies to engineer genomes and cells.

Greenblatt and his team have unveiled vertebral skeletal stem cells (vSSCs) as a critical player in the landscape of bone metastasis. This commentary delves into the transformative discoveries surrounding vSSCs, emphasizing their distinct role in bone metastasis compared to other stem cell lineages. We illuminate the unique properties and functions of vSSCs, which may account for the elevated susceptibility of vertebral bones to metastatic invasion. Furthermore, we explore the exciting therapeutic horizons opened by this newfound understanding. These include potential interventions targeting vSSCs, modulation of associated signaling pathways, and broader implications for the treatment and management of bone metastasis. By shedding light on these game-changing insights, we hope to pave the way for novel strategies that could revolutionize the prognosis and treatment landscape for cancer patients with metastatic bone disease.

Introduction and purpose Diabetes is a disease resulting from impaired action or secretion of insulin. The number of patients currently amounts to approximately 422 million, and approximately 1.5 million deaths per year are directly attributed to this disease. Diabetes significantly reduces the quality of life and, if poorly controlled, can lead to serious complications. Mesenchymal stem cells are multipotent cells capable of differentiation. They have the ability to self-renew and have a modulating function. There are reports that they can be used in the treatment of this disease. The aim of the review was to present a new method of therapy and their possible effects. Material and methods The review was based on articles obtained from PubMed scientific database in the years 2015-2023, using the following keywords: diabetes mellitus, stem cells, diabetes complications. Results Implanted stem cells are able to transform into cells that produce and secrete insulin, and also enable better glycemic control. They can alleviate chronic inflammation and reduce fibrosis. Taking into account the complications that occur during long-term diabetes, the use of stem cells may be associated with improving the function of specific organs and tissues such as the kidneys, heart, eyes and nerves. Studies also report a positive effect of these cells on the healing process of wounds and ulcers. Conclusions Stem cells are a promising object of analysis. They can control glycemia and have a positive effect on the functioning of the kidneys, heart, eyes and nerves, and accelerate wound healing, but further, extensive research is needed to assess the effectiveness and safety of this therapy. [ABSTRACT FROM AUTHOR]

Background: Congenital bladder disorders in children necessitate innovative approaches for bladder tissue regeneration, aiming to minimize complications associated with conventional therapies. This study focused on generating a cell-seeded scaffold using superior smooth muscle cells (SMCs) by exploring the potential of smooth muscle cell spheroids (3D SMCs) compared to conventionally cultured SMCs (2D SMCs) for bladder tissue engineering. Additionally, adipose-derived stem cells (ADSCs) were investigated for their impact on SMC proliferation and maturation, and pre-differentiated smooth muscle-like ADSCs (pADSCs) for their potential as alternative cell source. Methods: 3D SMCs were seeded into a compressed collagen scaffold as monoculture and as co-culture with ADSCs or pADSCs and incubated for 2 weeks. Their contractile potential as well as proliferation and cell distribution within the scaffold were compared to conventionally cultured 2D SMCs by immunofluorescent staining and qRT-PCR. Results: 3D SMCs in collagen scaffolds exhibited significantly superior cell distribution, proliferation, and contractile marker expression compared to 2D SMCs. While ADSCs showed limited impact, co-culture with pADSCs enhanced contractile marker expression, though not surpassing 3D SMC monoculture. Conclusion: For the first time, a collagen scaffold seeded with 3D SMCs was generated and evaluated. This study recommends 3D SMCs as optimal building blocks for bladder tissue engineering, highlighting the potential of pADSCs as an alternative cell source. These findings offer crucial insights for refining cell sources as well as culture techniques in pediatric bladder regeneration and provide a superior cell-seeded scaffold for further bladder tissue engineering experiments. [ABSTRACT FROM AUTHOR]

Myocardial infarction, the most severe manifestation of coronary artery disease, is a leading cause of mortality worldwide. Here, a novel nanotherapy engineering approach is reported for enhancing therapeutic effects of mesenchymal stem cells (MSCs) on myocardial ischemia‐reperfusion (MI/R) injury. An anti‐oxidative and anti‐inflammatory nanotherapy (TPCD NP) is first fabricated. MSCs are successfully engineered with TPCD NP by endocytosis, and TPCD NP engineering does not affect stemness of MSCs. TPCD NP‐internalized MSCs (tn‐MSCs) are resistant to oxidative stress, cytotoxicity, and apoptosis induced by reactive oxygen species (ROS). Under oxidative distress, tn‐MSCs show stronger paracrine activity compared to MSCs. Consistently, tn‐MSCs effectively enhance angiogenesis of endothelial cells under pathological conditions. Also, tn‐MSCs protect cardiomyocytes from ROS‐induced cytotoxicity and apoptosis by improving mitochondrial membrane potential and regulating the p53 signaling pathway. In mice with MI/R injury, the survival time of tn‐MSCs in the injured heart is prolonged, compared to pristine MSCs. Correspondingly, tn‐MSCs more significantly reduce the infarct size, improve cardiac function, and promote cardiac remodeling in MI/R injury mice. Mechanistically, tn‐MSCs alleviate MI/R injury by attenuating oxidative stress and inflammation, inhibiting cardiomyocyte apoptosis, and promoting cardiac repair. Consequently, tn‐MSCs are promising for treating cardiovascular diseases linked to oxidative distress and inflammation. [ABSTRACT FROM AUTHOR]

ABSTRACT Background and Objective Methods and Results Conclusions CEFFE (Cell‐free fat extract) treatment for periocular fine lines requires thorough clinical evaluation to determine its efficacy and safety in enhancing skin quality. The research enrolled 10 healthy female participants aged 31–58, focusing on skin texture, elasticity, and barrier function.CEFFE treatment demonstrated significant benefits, with notable improvements observed as early as 3 months posttreatment, which continued throughout the 12‐month follow‐up period. Objective assessments revealed reductions in SEr% and SEw%, indicative of reduced skin roughness and wrinkles, particularly pronounced after the third month of treatment. Enhanced skin elasticity, as indicated by improvements in R2%, R5%, and R7%, was observed, with the most significant enhancements noted at the 6‐month follow‐up. Furthermore, TEWL decreased consistently, highlighting CEFFE's potential in maintaining the skin's barrier function and moisture retention. High patient satisfaction levels, with 70% expressing satisfaction ranging from satisfied to very satisfied, underscored CEFFE's clinical significance.CEFFE demonstrates potential as an effective and safe intervention for addressing periocular fine lines, providing a solution for fine lines while ensuring skin health (ChiCTR1900024329). [ABSTRACT FROM AUTHOR]

The beneficial effects of Neural Precursor Cell (NPC) transplantation in several neurological disorders are well established and they are generally mediated by the secretion of immunomodulatory and neurotrophic molecules. We therefore investigated whether Rett syndrome (RTT), that represents the first cause of severe intellectual disability in girls, might benefit from NPC-based therapy. Using in vitro co-cultures, we demonstrate that, by sensing the pathological context, NPC-secreted factors induce the recovery of morphological and synaptic defects typical of Mecp2 deficient neurons. In vivo, we prove that intracerebral transplantation of NPCs in RTT mice significantly ameliorates neurological functions. To uncover the molecular mechanisms underpinning the mediated benefic effects, we analyzed the transcriptional profile of the cerebellum of transplanted animals, disclosing the possible involvement of the Interferon γ (IFNγ) pathway. Accordingly, we report the capacity of IFNγ to rescue synaptic defects, as well as motor and cognitive alterations in Mecp2 deficient models, thereby suggesting this molecular pathway as a potential therapeutic target for RTT. Synopsis: To address the unmet need for a cure for RTT, the therapeutic potential of adult Neural Precursor Cells (NPCs) was investigated in vitro on Mecp2 deficient neurons and in vivo in transplanted Mecp2 deficient mice. NPC-secreted molecules rescue typical phenotypes of Mecp2 deficient neurons in culture. NPCs do not require Mecp2 to exert their beneficial effects. Intracerebral transplantation of NPCs prolongs the lifespan of Mecp2 null mice and restores their memory and motor functions. RNA-sequencing studies on transplanted brains have indicated the activation of the IFNγ pathway as a possible mechanism of action. IFNγ treatment of Mecp2 deficient animals and neurons confirms the therapeutic efficacy of the cytokine for RTT. To address the unmet need for a cure for RTT, the therapeutic potential of adult Neural Precursor Cells (NPCs) was investigated in vitro on Mecp2 deficient neurons and in vivo in transplanted Mecp2 deficient mice. [ABSTRACT FROM AUTHOR]

Depression is a common affective disorder characterized by persistent low mood, diminished interest or pleasure in normally enjoyable activities, disturbances in sleep patterns, and suicidal ideation. Conventional treatments often yield unsatisfactory results and are associated with several adverse effects. However, emerging literature has highlighted the potential of stem cell (SC) transplantation as a promising avenue for treating depression owing to its favorable anti-inflammatory and neurotrophic properties. This review summarizes the therapeutic effects and underlying mechanisms associated with SC transplantation in depression, offering a conceptual framework for the future application of SCs in the clinical treatment of depression. [ABSTRACT FROM AUTHOR]

Thalassemia and leukemia and related blood disorders are approved for blood stem cell transplants in India, for a stem cell transplant to be successful, the human leukocyte antigen (HLA) complex located on the arm of chromosome six must be a match between the cord blood donor and the recipient. In the quest to find an exact blood stem cell match for an individual, the HLA becomes the node at the center of community genetics where the HLA match is sought (not necessarily successful) in the extended family, the same caste, language, and ethnic (both national and the diaspora) groups. By considering thalassemia as a case study, how do we understand personalized stem cell therapies within biobanking infrastructures in Chennai? How do social categories get entwined with biological materials like cord blood? [ABSTRACT FROM AUTHOR]

Stem cells regenerate differentiated cells to maintain and repair tissues and organs. They also replenish themselves, i.e. self-renew, to support a lifetime of regenerative capacity. Here we study the renewal of skeletal muscle stem cell (MuSC) during regeneration. The transcriptional co-factors TAZ/YAP (via the TEAD transcription factors) regulate cell cycle and growth while the transcription factor YY1 regulates metabolic programs for MuSC activation. We show that MPP7 and AMOT join TAZ and YY1 to regulate a selected number of common genes that harbor TEAD and YY1 binding sites. Among these common genes, Carm1 can direct MuSC renewal. We demonstrate that the L27 domain of MPP7 enhances the interaction as well as the transcriptional activity of TAZ and YY1, while AMOT acts as an intermediate to bridge them together. Furthermore, MPP7, TAZ and YY1 co-occupy the promoters of Carm1 and other common downstream genes. Our results define a renewal program comprised of two progenitor transcriptional programs, in which selected key genes are regulated by protein-protein interactions, dependent on promoter context. Synopsis: Renewal divisions of muscle stem cells are regulated by the methyltransferase CARM1. This study shows that Carm1 is transcriptionally regulated by the coordinated action of MPP7, AMOT, YAP/TAZ, and YY1. Mpp7 cKO and Amot cKO mice display similar muscle stem cell renewal defects. Mpp7 cKO, Amot cKO, and Yap/Taz double cKO transcriptomes reveal a common set of down-regulated genes, including Carm1. MPP7, AMOT, YAP/TAZ, and YY1 form a protein complex to activate Carm1 transcription. The L27 domain of MPP7 facilitates complex formation and contributes to the enhanced transcriptional activity. Renewal divisions of muscle stem cells are regulated by the methyltransferase CARM1. This study shows that Carm1 is transcriptionally regulated by the coordinated action of MPP7, AMOT, YAP/TAZ, and YY1. [ABSTRACT FROM AUTHOR]

Background: In diagnosing chronic orthopedic implant infections culture of sonicate represents a supplement to tissue cultures. However, the extent to which biofilm forms on implant surfaces and the degree of dislodgement of bacteria by sonication remains unclear. In this in vivo study using a low bacterial inoculum, we aimed to determine whether a variable effect of sonication could be observed in a standardized in vivo model. Materials and Methods: Seven Wistar rats underwent surgery with intramuscular implantation of two bone xenograft implants, each containing two steel plates. The grafts were inoculated with approximately 500 colony forming units (CFU) of Staphylococcus epidermidis ATCC 35984. After 20 days the rats were sacrificed, and the steel plates were removed from the bone grafts. Epifluorescence microscopy and scanning electron microscopy (SEM) were used to visualize biofilm formation and dislodgement on the plate surfaces. In addition to cultures of sonicate, a quantitative S. epidermidis specific PCR was developed for enumeration of bacteria. Results: A chronic, low-grade implant infection was successfully established, with all animals remaining in good health. All infected bone graft implants yielded abundant growth of S. epidermidis, with a median of 3.25 (1.6–4.6) × 10⁷ CFU per/graft. We were unable to distinguish infected plates from negative controls using epifluorescence microscopy. On infected plates small colonies of staphylococci were identified by SEM. The number of bacteria detected in the sonicate was low with 500 (100–2400) CFU/plate and 475 (140–1821) copies/plate by qPCR. The difference in area covered by fluorescent material before and after sonication was 10.1 (5.7–12.3) %, p = 0.018. Conclusion: Despite the pronounced infection in the surrounding tissue, only few bacteria were detected on the surface of the steel implants. This is evident from the minimal findings by SEM before sonication, as well as the very low CFU counts and DNA copies in the sonicate. Sonication did not show variable effectiveness, indicating it is a valuable addition to, but not a replacement for biopsy cultures in cases of implant-associated infections with low-virulence microorganisms. [ABSTRACT FROM AUTHOR]

Epidermal stem cells control homeostasis and regeneration of skin and hair. In the hair follicle (HF) bulge of mammals, populations of slow-cycling stem cells regenerate the HF during cyclical rounds of anagen (growth), catagen (regression), and telogen (quiescence). Multipotent epidermal cells are also present in the HF above the bulge area, contributing to the formation and maintenance of sebaceous gland and upper and middle portions of the HF. Here, we report that the transcription factor KROX20 is enriched in an epidermal stem cell population located in the upper/middle HF. Expression analyses and lineage tracing using inducible Krox20-CreERT showed that Krox20-lineage cells migrate out of this HF region and contribute to the formation of the bulge in the HF, serving as ancestors of bulge stem cells. In vivo depletion of these cells arrests HF morphogenesis. This study identifies a marker for an epidermal stem cell population that is indispensable for hair homeostasis. [ABSTRACT FROM AUTHOR]

AbstractThe inherent adaptability of human mesenchymal stromal cells (hMSCs) to differentiate into neural lineages provides a valuable resource for investigating potential neurotoxicity in humans. By harnessing the ability of hMSCs to transform into astrocytes, we can evaluate the effects of various agents on these vital cells. Our protocol employs hMSCs sourced from umbilical cord tissue, ensuring a readily available supply of high-quality cells. The hMSC-to-neural workflow encompasses six essential steps: hMSC culture, followed by the generation of embryoid bodies (EBs) from these cells on specialized surfaces. Next, EBs and cells are expanded in a growth-promoting medium, directing them toward neural lineages. Subsequent differentiation into immature astrocytes is achieved through the use of specific factors. The process continues with the maturation of EBs/cells into astrocyte-like cells (hALCs) under optimized conditions, culminating in the final development of hALCs in a specialized medium. This methodology yields cells that display astrocyte morphology and express characteristic markers such as GFAP and S100β. The protocol is efficient, requiring roughly 6 weeks to generate hALCs from primary hMSCs without genetic manipulation. The application of hMSCs in evaluating cell damage triggered by neurotoxicants like MeHg and MGO underscores their potential as a valuable component within a more extensive battery of neurotoxicity tests. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is a severe blood cancer with less than 50 % long-term survival. Despite advancements in treatment options, relapse is still the major obstacle. The main reason of this problem is ineffective targeting of leukemic stem cells (LSCs), which play an important role in tumor development and relapse. In our previous studies, we found that casticin, the major polyphenolic component of Vitex trifolia’s fruit, targets both leukemic cells and LSCs without affecting healthy tissues. Therefore, in this study, we aimed to investigate the effect of casticin-mediated cell death in relation to the LSCs-favored survival pathways at gene and protein expression levels using in vitro LSC-like and parental leukemic cell models.We validated the LSC character of KG1a and KG1 cells (84.55 % CD34+, CD38- and 93.55 % CD34+, CD38+, respectively) by flow cytometry. For the investigation of casticin’s mechanism of action, we employed real time-PCR, western blotting and bioinformatics analyses.Our results showed an increase in cleaved PARP/β-actin ratio but no change in LC3BI/II and SQSTM/β-actin ratios. Our gene expression, bioinformatics and immunoblotting analyses represented significant decrease in Shh, Gli and Wnt levels. We also elucidated a possible crosstalk between Hedgehog and other oncogenic cascades via the Gli, Notch, YAP, p38, Mcl-1, and Myc proteins in casticin mediated anti-leukemic effect.In conclusion, we found that casticin induces apoptosis in both LSC-like and parental leukemia cells mainly by suppressing Shh signaling, which is crucial for LSC survival and AML relapse. [ABSTRACT FROM AUTHOR]

Intestinal stem cells (ISCs) are highly vulnerable to damage, being in a constant state of proliferation. Reserve stem cells repair the intestinal epithelium following damage-induced ablation of ISCs. Here, we report that the epigenetic regulator plant homology domain (PHD) finger protein 16 (PHF16) restores homeostasis of the intestinal epithelium after initial damage-induced repair. In Phf16 −/Y mice, revival stem cells (revSCs) showed defects in exiting the regenerative state, and intestinal crypt regeneration failed even though revSCs were still induced in response to tissue damage, as observed by single-cell RNA sequencing (scRNA-seq). Analysis of Phf16 −/Y intestinal organoids by RNA sequencing (RNA-seq) and ATAC sequencing identified that PHF16 restores homeostasis of the intestinal epithelium by inducing retinoic acid receptor (RAR)/retinoic X receptor (RXR) target genes through HBO1-mediated histone H3K14 acetylation, while at the same time counteracting YAP/TAZ activity by ubiquitination of CDC73. Together, our findings demonstrate the importance of timely suppression of regenerative activity by PHF16 for the restoration of gut homeostasis after acute tissue injury. [Display omitted] • PHF16 is required for intestinal regeneration following irradiation • PHF16 is essential for timely exit from the regenerative phase • The PHF16/HBO1 complex promotes the differentiation of revival stem cells • PHF16 functions as an E3 ligase for CDC73 to suppress the expression of fetal genes Ahn and Kim et al. report that PHF16 controls the timely termination of intestinal injury response and the completion of regeneration. PHF16 promotes the expression of differentiation genes through its interaction with the HBO1 complex, while also acting as an E3 ligase for CDC73 to suppress the expression of fetal genes. [ABSTRACT FROM AUTHOR]

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Cell and Gene therapy are referred to as advanced therapies that represent overlapping fields of regenerative medicine. They have similar therapeutic goals such as to modify cellular identity, improve cell function, or fight a disease. These two therapeutic avenues, however, possess major differences. While cell therapy involves introduction of new cells, gene therapy entails introduction or modification of genes. Furthermore, the aim of cell therapy is often to replace, or repair damaged tissue, whereas gene therapy is used typically as a preventive approach. Diabetes mellitus severely affects the quality of life of afflicted individuals and has various side effects including cardiovascular, ophthalmic disorders, and neuropathy while putting enormous economic pressure on both the healthcare system and the patient. In recent years, great effort has been made to develop cutting-edge therapeutic interventions for diabetes treatment, among which cell and gene therapies stand out. This review aims to highlight various cell- and gene-based therapeutic approaches leading to the generation of new insulin-producing cells as a topmost "panacea" for treating diabetes, while deliberately avoiding a detailed molecular description of these approaches. By doing so, we aim to target readers who are new to the field and wish to get a broad helicopter overview of the historical and current trends of cell- and gene-based approaches in β-cell regeneration. [ABSTRACT FROM AUTHOR]

Chronic pathological conditions often induce persistent systemic inflammation, contributing to neuroinflammatory diseases like Multiple Sclerosis (MS). MS is known for its autoimmune-mediated damage to myelin, axonal injury, and neuronal loss which drive disability accumulation and disease progression, often manifesting as cognitive impairments. Understanding the involvement of neural stem cells (NSCs) and neural progenitor cells (NPCs) in the remediation of MS through adult neurogenesis (ANG) and gliogenesis—the generation of new neurons and glial cells, respectively is of great importance. Hence, these phenomena, respectively, termed ANG and gliogenesis, involve significant structural and functional changes in neural networks. Thus, the proper integration of these newly generated cells into existing circuits is not only key to understanding the CNS's development but also its remodeling in adulthood and recovery from diseases such as MS. Understanding how MS influences the fate of NSCs/NPCs and their possible neuroprotective role, provides insights into potential therapeutic interventions to alleviate the impact of MS on cognitive function and disease progression. This review explores MS, its pathogenesis, clinical manifestations, and its association with ANG and gliogenesis. It highlights the impact of altered NSCs and NPCs' fate during MS and delves into the potential benefits of its modifications. It also evaluates treatment regimens that influence the fate of NSCS/NPCs to counteract the pathology subsequently. [ABSTRACT FROM AUTHOR]

Background Current guidelines advocate a shared decision-making process approach to erectile dysfunction management, and while there is growing interest in regenerative therapies such as stem cell therapy, platelet-rich plasma injections, and low-intensity shockwave therapy for erectile dysfunction, comparative data on the efficacy of these modalities are limited. Aim This systematic review and network meta-analysis aims to compare stem cell therapy, platelet-rich plasma injections, and low-intensity shockwave therapy for managing erectile dysfunction and quantify their impact on the International Index of Erectile Function (IIEF). Methods In January 2024, a systematic search of online databases was performed to identify randomized clinical trials related to stem cell therapy, platelet-rich plasma injections, and low-intensity shockwave therapy in erectile dysfunction. Eligible articles reported outcomes using the IIEF score. Data were inputted into Review Manager 5.4 for pairwise meta-analysis. Data were then used to build a network in R Studio. These networks were used to model 200 000 Markov Chains via MonteCarlo sampling. The results are expressed as standardized mean difference (SMD) with 95% credible intervals (CrI). Meta-regression was used to adjust for PDE5is use. Outcomes Impact on the International Index of Erectile Function. Results A total of 16 studies involving 907 patients were analyzed. The standardized mean difference (SMD) vs control for stem cell therapy was 0.92 [95% CrI –0.49, 2.3]. For platelet-rich plasma, the SMD vs control was 0.83 [95% CrI 0.15, 1.5], and for low-intensity shockwave therapy, the SMD vs control was 0.84 [95% CrI 0.49, 1.2]. When stratifying low-intensity shockwave therapy by dose, the SMD vs control at 0.15 mJ/mm2 was 1.1 [95% CrI 0.36, 1.9], while at 0.09 mJ/mm2, it was 0.75 [95% CrI 0.26, 1.2]. Meta-regression adjusting for the administration of PDE5 inhibitors yielded non-significant results. Clinical implications The findings suggest that stem cells, platelet-rich plasma, and low intensity shockwave therapy, particularly at 0.15 and 0.09 mJ/mm2, may offer improvements in erectile function. Strengths and limitations The strength is the robust statistical methods. Limitations are in heterogeneity in control groups and follow-up durations among included studies. Conclusion Shockwave therapy and platelet-rich plasma demonstrated statistically significant improvements, though the clinical relevance and extent of their impact remain questionable. Further research is necessary to determine the efficacy of stem cell therapies for erectile function. [ABSTRACT FROM AUTHOR]

Background: One-step cell-based techniques of cartilage repair that lead to restoration of durable chondral tissue and long-term maintenance of joint function are cost-effective and ideal for routine use. Purposes: To examine the long-term clinical outcomes, after a mean follow-up duration of 14 years, of cartilage repair in the knee using a hyaluronic acid–based scaffold in association with bone marrow aspirate concentrate (HA-BMAC) and to evaluate the effect of age, lesion characteristics, and associated treatments on the outcome of this cartilage repair method. Study Design: Case series; Level of evidence, 4. Methods: Patients were followed prospectively for a mean duration of 14.0 years after undergoing treatment of knee full-thickness articular cartilage injury using HA-BMAC. Clinical evaluation consisted of the patient-reported scoring tools of the visual analog scale and the Knee injury and Osteoarthritis Outcome Score, which were completed preoperatively and at the time of final follow-up. Results: A total of 26 patients with a mean age of 48.3 years (17 male, 9 female) and median chondral lesion size of 6.6 cm2 (range, 1-27 cm2) were followed prospectively. There were 3 treatment failures, and 1 patient who underwent medial compartment unicompartmental arthroplasty 12 years after HA-BMAC treatment of patellar chondral injury. Of the 22 remaining patients, after a mean final follow-up duration of 14.0 years (range, 12-16 years), the median visual analog scale score of 0.6 was significantly decreased from the preoperative median score of 5.0 (P <.001). The median Knee injury and Osteoarthritis Outcome Score Pain (92), Symptoms (86), Activities of Daily Living (96), Sports (85), and Quality of Life (88) subscale values were all increased compared with the preoperative scores (P ≤.001). There was no correlation of clinical outcome score and body mass index. Conclusion: One-step cartilage repair of full-thickness chondral defects in the knee using an HA-BMAC led to successful long-term clinical outcomes and maintenance of joint junction after a mean follow-up duration of 14 years. Long-term clinical success in active, nonobese patients has been uniformly demonstrated across a wide range of patient ages and lesion types, including cases of multicompartment involvement, treatment of associated conditions, and large or bipolar chondral lesions. [ABSTRACT FROM AUTHOR]

Microglia identity is determined by intersecting developmental and environmental transcriptional networks and can be induced by forced expression of key lineage transcription factors (TFs) in human pluripotent stem cells. Forward programming has emerged as a powerful tool for efficient bulk generation of microglia. Key determinants of forward programming are the choice of TFs, their mode of gene delivery, and environmental cues. Forward programming, classical directed differentiation, and blood monocyte reprogramming are diverse and complementary tools for the study of human microglia in vitro. Standardisation of human microglia cultures is key for the interpretation of future downstream analysis. Microglia play vital roles in embryonic and post-natal development, homeostasis, and pathogen defence in the central nervous system. Human induced pluripotent stem cell (hiPSC)-based methods have emerged as an important source for the study of human microglia in vitro. Classical approaches to differentiate hiPSCs into microglia suffer from limitations including extended culture periods, consistency, and efficiency. More recently, forward programming has arisen as a promising alternative for the manufacture of bulk quantities of human microglia. This review provides a comprehensive assessment of published forward programming protocols that are based on forced expression of key lineage transcription factors (TFs). We focus on the choice of reprogramming factors, transgene delivery methods, and medium composition, which impact induction kinetics and the resulting microglia phenotype. [ABSTRACT FROM AUTHOR]