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At least 19 recordsLinked to original sources

Repair and regeneration across the lifespan: an ontogenetic perspective.

The capacity for tissue repair and regeneration undergoes a profound and progressive decline across the human lifespan, representing a fundamental driver of aging and chronic disease. This review establishes a comprehensive ontogenetic framework by mapping the continuous biological transition from the flawless, scarless regenerative plasticity of embryonic development to the irreversible fibrotic scarring and organ failure characteristic of senescence. We synthesize the hierarchical collapse of reparative networks across multiple biological scales. Importantly, this ontogenetic decline should not be interpreted as a purely degenerative trajectory but rather as a dynamic systems-level reprogramming in which evolutionary trade-offs prioritize tumor suppression, immune surveillance, and reproductive fitness over long-term regenerative fidelity. Recognizing this adaptive reallocation of biological resources reframes aging not simply as failure but as a predictable recalibration of repair hierarchies. At the molecular and cellular levels, the accumulation of genomic instability, unresolvable DNA damage, and mitochondrial dysfunction gradually overwhelms intracellular quality-control mechanisms. Concurrently, epigenetic drift and chronic, low-grade systemic inflammation ("inflammaging") dismantle the stem cell niche, driving adult stem cell exhaustion and shifting wound healing away from functional tissue replacement toward maladaptive fibrosis. Furthermore, we examine divergent, organ-specific repair trajectories. By contrasting the severe regenerative restrictions of the adult central nervous system and myocardium with the persistent, yet exhaustible, resilience of the liver, we elucidate the unique intrinsic and microenvironmental barriers that impede structural and functional recovery. Finally, we evaluate the clinical paradigm shift from passive management of age-related degeneration to active restoration of tissue integrity. By integrating systemic geroscience-which addresses the global hallmarks of aging-with targeted bioengineering and in vivo epigenetic modulation, contemporary regenerative medicine seeks to recreate permissive, youthful microenvironments. Ultimately, mastering these ontogenetic principles holds unprecedented potential to reactivate endogenous repair pathways, mitigate multi-organ collapse, and significantly extend human functional healthspan.

DNA repair

Aging of hair follicle stem cells and their niche: mechanisms and regenerative therapeutic strategies.

Hair follicles (HFs) are vital skin appendages that perform fundamental functions including protection, thermoregulation, and sensation. Orchestrated by hair follicle stem cells (HFSCs), HFs undergo cyclic regeneration throughout the lifespan. However, during chronological aging, this mini-organ experiences progressive physiological decline, clinically characterized by a marked reduction in hair density and hair graying due to pigmentation dysfunction. This aging process involves HFSC exhaustion accompanied by diminished regenerative potential and differentiation capacity, leading to degenerative changes in the bulge architecture. Concurrently, the niche supporting HFSC homeostasis undergoes multi-dimensional and systemic degradation. This niche deterioration disrupts the delicate balance between HFSC quiescence and activation, further impeding hair regeneration. In this review, we delineate the dynamic anatomical changes throughout the hair growth cycle and describe the alterations of HFSCs during aging. We specifically focus on the mechanisms underlying the multi-dimensional degradation of the HFSC niche at tissue, cellular, and molecular levels. Furthermore, we discuss various therapeutic strategies aimed at ameliorating HF aging, offering potential insights for future clinical translation in hair regeneration. Finally, we propose that integrating spatiotemporal high-resolution technologies with genomic data to further decipher the spatiotemporal behaviors of aging HFSCs and niche cells will facilitate the establishment of a robust mechanistic framework for HFSC and niche aging.

Hair Follicle

Putative glioblastoma origin-like cells in the subventricular zone: isolation and characterization.

Glioblastoma (GBM) remains lethal despite maximal therapy. The adult subventricular zone (SVZ), a neural stem-cell niche, has been implicated as a potential site of origin, yet the identity and functional properties of putative GBM origin-like cells (GBM-OCs) within the SVZ remain unclear. An SVZ-restricted somatic mutation mouse model (Cre-induced EGFRvIII expression with Trp53 and Pten disruption) was established and mouse SVZ-derived cells were prospectively isolated for functional and molecular profiling. Self-renewal, multipotency, invasive potential and tumour-initiating capacity were assessed relative to control SVZ cells and matched tumour-derived tumourspheres. Whole-genome and RNA sequencing defined genomic and transcriptional alterations during early progression. Mouse GBM-OCs exhibited self-renewal and multilineage differentiation and initiated tumours only after re-implantation into the SVZ (11/29, 38%), whereas direct striatal implantation failed (0/25, 0%), indicating context-dependent tumorigenic potential associated with the SVZ microenvironment. In contrast, tumour-derived tumourspheres retained tumorigenic capacity upon implantation into both the SVZ and the striatum. During progression from mouse GBM-OCs to tumours, whole-chromosome and arm-level aneuploidies accumulated. In patients with GBM, multi-region single-nucleus RNA sequencing of tumour-free SVZ, matched tumours and tumour-free cortex identified rare neural stem cell-like, astrocyte-like and oligodendrocyte precursor-like SVZ populations transcriptionally aligned with GBM programmes. These cells showed single-nucleus RNA-inferred chromosome 7 gain and/or chromosome 10 loss signals, with concordant low-frequency copy-number alterations in the SVZ detected by exome sequencing and enriched in matched tumours. Together, these findings support the presence of SVZ-resident stem or progenitor-like populations with early GBM-associated features, consistent with putative GBM-OCs, and highlight the SVZ niche as a potential target for early detection and niche-informed therapeutic strategies.

Animals

The relationship between the spleen colony-forming cell and the haemopoietic stem cell.

Several experimental findings that are inconsistent with the view that the spleen colony-forming cell (CFU-S) is the primary haemopoietic stem cell are reviewed. Recovery of CFU-S, both quantitatively and qualitatively, can proceed differently depending upon the cytotoxic agent or regime used to bring about the depletion. The virtual immortality of the stem cell population is at variance with evidence that the CFU-S population has an 'age-structure' which has been invoked by several workers to explain experimental and clinical observations. To account for these inconsistencies, a hypothesis is proposed in which the stem cell is seen in association with other cells which determine its behaviour. It becomes essentially a fixed tissue cell. Its maturation is prevented and, as a result, its continued proliferation as a stem cell is assured. Its progeny, unless they can occupy a similar stem cell 'niche', are first generation colony-forming cells, which proliferate and mature to acquire a high probability of differentiation, i.e., they have an age-structure. Some of the experimental situations reviewed are discussed in relation to the proposed hypothesis.

Animals

Cloning and validating systems for high throughput molecular recording.

Molecular recording technologies record and store information about cellular history. Lineage tracing is one form of molecular recording and produces information describing cellular trajectories during mammalian development, differentiation and maintenance of adult stem cell niches, and tumor evolution. Our molecular recorder technology utilizes CRISPR-Cas9 barcode editing to generate mutations in genomically integrated, engineered DNA cassettes, which are read out by single-cell RNA sequencing and used to produce high-resolution lineage trees. Here, we describe optimized cloning and validation procedures to construct the molecular recorder lineage tracing system. We include information on considerations of technology design, cloning procedures, the generation of lineage tracing cell lines, and time course experiments to assess their performance.

Cloning, Molecular

Radiation Without Borders: Unraveling Bystander and Non-Targeted Effects in Oncology.

Radiotherapy (RT) remains a cornerstone of cancer treatment, offering spatially precise cytotoxicity against malignant cells. However, emerging evidence reveals that ionizing radiation (IR) exerts biological effects beyond the targeted tumor volume, manifesting as radiation bystander effects (BEs) and other non-targeted effects (NTEs). These phenomena challenge the traditional paradigm of RT as a localized intervention, highlighting systemic and long-term consequences in non-irradiated tissues. This comprehensive review synthesizes molecular, cellular, and clinical insights about BEs, elucidating the complex intercellular signaling networks gap junctions, cytokines, extracellular vesicles, and oxidative stress that propagate damage, genomic instability, and inflammation. We explore the role of mitochondrial dysfunction, epigenetic reprogramming, immune modulation, and stem cell niche disruption in shaping BEs outcomes. Clinically, BEs contribute to neurocognitive decline, cardiovascular disease, pulmonary fibrosis, gastrointestinal toxicity, and secondary malignancies, particularly in pediatric and long-term cancer survivors. The review also evaluates countermeasures including antioxidants, COX-2 inhibitors, exosome blockers, and FLASH RT, alongside emerging strategies targeting cfCh, inflammasomes, and senescence-associated secretory phenotypes. We discuss the dual nature of BEs: their potential to both harm and heal, underscoring adaptive responses and immune priming in specific contexts. By integrating mechanistic depth with translational relevance, this work posits that radiation BEs are a modifiable axis of RT biology. Recognizing and mitigating BEs is imperative for optimizing therapeutic efficacy, minimizing collateral damage, and enhancing survivorship outcomes. This review advocates for a paradigm shift in RT planning and post-treatment care, emphasizing precision, personalization, and systemic awareness in modern oncology.

Humans

Differentiation latency and dormancy signatures define fetal liver hematopoietic stem cells at single-cell resolution.

Decoding the mechanisms governing the self-renewal of hematopoietic stem cells (HSCs) during their expansion in the fetal liver (FL) could unlock novel therapeutic strategies to expand transplantable HSCs, a long-standing challenge. To explore intrinsic and extrinsic regulation of FL-HSC self-renewal at single-cell resolution, we engineered a culture platform replicating the FL endothelial niche that supports the amplification of serially engraftable HSCs. Leveraging this platform together with single-cell index flow cytometry, live imaging, transplantation assays, and single-cell RNA sequencing, we demonstrate that differentiation latency, cell-division symmetry, and transcriptional signatures of biosynthetic dormancy are distinguishing properties of rare FL-HSCs capable of serial multilineage hematopoietic reconstitution. Our findings support a paradigm in which intrinsic programs and niche-derived signals together facilitate the symmetric self-renewal of FL-HSCs while delaying their active participation in hematopoiesis. Our study also provides a resource for future investigations into intrinsic and extrinsic signaling pathways governing FL-HSC self-renewal.

Hematopoietic Stem Cells

Biomimetic Hydrogels with Nucleus Pulposus-like Viscoelasticity and ECM Peptides for Discogenic Differentiation of Stem Cells.

Intervertebral disc (IVD) degeneration is a leading cause of low back pain (LBP), primarily originating in the nucleus pulposus (NP). Regenerative strategies combining mesenchymal stem cells (MSCs) with biomaterials offer great potential for NP repair by replenishing cells and restoring extracellular matrix (ECM). However, key translational challenges remain, including limited stem cell differentiation, poor cell survival in the harsh degenerative niche, and insufficient biomaterial support. While matrix viscoelasticity has been shown to influence adipose-derived stem cell (ASC) discogenic differentiation, its interplay with cell-adhesive ligands for IVD regeneration remains unclear. Moreover, most current hydrogels fail to replicate the ultrafast stress relaxation properties of native non-degenerative human NP tissue. Here, we developed viscoelastic ECM peptide-functionalized hydrogels (VEPH), specifically designed to mimic healthy human NP biomechanics and promote ASC differentiation for NP regeneration. We biochemically conjugated NP ECM-derived adhesive peptides (IKVAV, hA5G26, CHAD) through maleimide-thiol click chemistry, achieving hydrogels with significantly faster stress relaxation (∼25 s) compared to conventional viscoelastic alginate hydrogels (>100 s). Our results demonstrated that VEPH supported >95% ASC viability and robust metabolic activity over 21 days in 3D culture. Notably, the IKVAV-functionalized hydrogel significantly enhanced ASC cell-matrix interactions, upregulated NP marker expression (KRT18, HIF-1α, ITGA3, and CD24), and promoted type-II collagen secretion, indicating an NP-committed cell fate. Our findings highlight the synergistic roles of matrix viscoelasticity and NP-specific biochemical cues in directing ASC discogenic differentiation and advancing novel biomaterial design for IVD regeneration.

cell-adhesive peptides

Transcriptional activation of regenerative hematopoiesis via microenvironmental sensing.

Transition between activation and quiescence states in hematopoietic stem and progenitor cells (HSPCs) is tightly governed by cell-intrinsic means and microenvironmental co-adaptation. Although this balance is fundamental for lifelong hematopoiesis and immunity, the underlying molecular mechanisms remain poorly defined. Multimodal analysis divulging differential transcriptional activity between distinct HSPC states indicates the presence of Fli-1 transcription factor binding motif in activated hematopoietic stem cells. We reveal that Fli-1 activity is essential during regenerative hematopoiesis in mice. Fli-1 directs activation programs while priming cellular sensory and output machineries, enabling HSPCs co-adoptability with a stimulated vascular niche through propagation of niche-derived angiocrine Notch1 signaling. Constitutively induced Notch1 signaling is sufficient to recuperate functional hematopoietic stem cells impairments in the absence of Fli-1, without leukemic transformation. Applying FLI-1 transient modified-mRNA transduction into latent adult human mobilized HSPCs, enables their niche-mediated expansion and superior engraftment capacities. Thus, decryption of stem cell activation programs offers valuable insights for immunological regenerative medicine.

Animals

Endothelial PERK restricts lymphoid regeneration by reducing DLL4-NOTCH3 signaling at the Pre-B niche.

Delayed immune recovery after hematopoietic stem cell (HSC) transplantation is associated with a poor clinical outcome. We study the role of unfolded protein response (ER stress) in hematopoietic regeneration within the bone marrow (BM) microenvironment. We reveal that BM endothelium PERK activation is a prominent feature of patients with leukemia and is a hallmark response in mice following ionizing irradiation. Ablating endothelial Perk boosts NOTCH ligand DLL4 expression and promotes DLL4-dependent early HSC and B progenitor regeneration. Single-cell analysis reveals that endothelial DLL4 activates NOTCH3 expressed by mesenchymal stroma cells, and that the PERK-DLL4 axis coordinates the regulation of lymphoid commitment. NOTCH3 is critical for the upregulation of IL7 following irradiation and the expansion of lymphoid progenitors. These findings not only unveil an ER stress-controlled vascular-stroma signaling mechanism in regenerative hematopoiesis but also highlight PERK blockade as a promising strategy to improve immune recovery after myeloablative transplantation.

CP: cell biology

Impaired stem cell migration and divisions in Duchenne muscular dystrophy revealed by live imaging.

Dysregulation of stem cell properties is a hallmark of many pathologies, but the dynamic behaviour of stem cells in their microenvironment during disease progression remains poorly understood. Using the mdx mouse model of Duchenne Muscular Dystrophy, we developed innovative live imaging of muscle stem cells (MuSCs) in vivo, and ex vivo on isolated myofibres. We show that mdx MuSCs have impaired migration and precocious differentiation through unbalanced symmetric divisions, driven by p38 and PI3K signalling pathways, in contrast to the p38-only dependence of healthy MuSCs. Cross-grafting shows that MuSC fate decisions are governed by fibre-independent cues, whereas their migration behaviour is determined by the myofibre niche. This study provides the first dynamic analysis of dystrophic MuSC properties in vivo, reconciling conflicting reports on their function. Our findings establish DMD as a MuSC disease with niche dysfunctions, offering strategies to restore stem cell functions for improved muscle regeneration.

Stem Cells

Engineering CRISPR nanoplatforms to deplete cancer stem cells: Delivery checkpoints, target plasticity, and clinical viability.

Cancer stem cells (CSCs) sustain tumor initiation, therapy resistance, and relapse, yet evade durable control because they switch phenotype, enter quiescence, shelter within protective niches, resist drug efflux, and share markers with normal stem cells. Programmable CRISPR editing can disable intracellular self-renewal dependencies that antibodies and small molecules cannot reach, whereas only nanoscale carriers can confine such editing to intended cells; neither component alone solves the CSC problem. This review reframes CSC-directed CRISPR nanomedicine as an integrated design problem. We examine why target plasticity defeats static single-marker targeting; the sequential delivery checkpoints spanning blood stability, organ selection, tumor penetration, CSC recognition, endosomal escape, and productive editing; and advanced architectures including organ-selective lipid nanoparticles, biomimetic and vesicle carriers, metal-organic frameworks, and logic-gated systems. Genotoxicity, immunogenicity, incomplete depletion, manufacturing reproducibility, and absent CSC-specific clinical evidence remain limiting. Clinical viability, not imminent cure, is the realistic near-term objective.

Neoplastic Stem Cells

Understanding proneural-mesenchymal transition using patient-derived glioma stem-like cell (GSC) organoids and engineered extracellular matrix.

Glioblastoma multiforme (GBM) is a highly aggressive, angiogenic WHO grade IV glioma marked by rapid progression, therapeutic resistance, and poor prognosis. A defining feature of GBM is the presence of glioma stem-like cells (GSCs), which reside in specialized perivascular niches and drive tumor progression, recurrence, and therapeutic resistance. The blood-brain barrier, coupled with the complex and dynamic tumor microenvironment, poses significant challenges for both treatment and mechanistic investigation. Current in vitro GBM models inadequately recapitulate the structural and biochemical cues of the native perivascular niche due to the absence of functional vasculature and brain-mimetic extracellular matrix (ECM), limiting their physiological relevance and predictive power. To address the limitations of existing in vitro GBM models, we developed a patient-derived glioma stem cells (GSC) derived Matrigel spheroid system that transitions into organoids and enables integration into engineered microenvironments. Our model incorporates GSC organoids representing proneural and mesenchymal GBM subtypes, a synthetic engineered extracellular matrix (eECM), and endothelial cells (ECs) seeded on the matrix surface. We evaluated the expression of subtype-specific, pro-angiogenic, stemness, and differentiation markers under increasingly complex co-culture conditions. Our results show that Matrigel-derived GSC spheroids progressively differentiate into organoids over two weeks, with significantly enhanced expression of cell-specific markers in the presence of ECs. Encapsulation of these organoids within eECM, combined with EC co-culture, further promoted cellular invasion and induction of GBM associated genes. This in situ encapsulation strategy enables real-time observation of GSC behavior in a tunable microenvironment that mimics key features of the native tumor niche. Together, this platform provides a physiologically relevant and modular in vitro system for investigating GBM pathophysiology. It holds promise for uncovering tumor-specific cellular dependencies, studying GSC-vascular interactions, and conducting high-throughput drug screening under controlled, biomimetic conditions.

Engineered extracellular matrix

Spatial profiling of the spleen in mouse and human myelofibrosis reveals complement-driven immune-stromal interactions as a therapeutic target.

Splenomegaly is a defining feature of myelofibrosis, yet the contribution of splenic mesenchymal stroma to disease progression remains unclear. We combined spatial and single-nucleus transcriptomics of patient spleens with spatial and single-cell transcriptomics, as well as imaging analyses, of murine spleens to map extramedullary hematopoiesis niches. Activated red pulp reticular cells localize near hematopoietic stem and progenitor cells, and early disease is characterized by marginal zone disruption with lymphoid depletion preceding stromal remodeling. Trajectory analyses reveal a shift in reticular cells from hematopoiesis-supportive to inflammatory and pro-fibrotic states, driven by macrophage- and megakaryocyte-derived signals that activate complement and induce tumor necrosis factor α (TNF-α), transforming growth factor β (TGF-β), extracellular matrix, and Thbs1 programs. Non-hematopoietic complement component C3 deficiency or pharmacological C3 inhibition suppresses these pathways, restores splenic architecture, and reduces splenomegaly and bone marrow fibrosis. These findings identify complement-dependent stromal reprogramming as a mechanism governing hematopoietic niches and as a targetable axis in myelofibrosis.

Animals

Nanobioreactor detection of space-associated hematopoietic stem and progenitor cell aging.

Human hematopoietic stem and progenitor cell (HSPC) fitness declines following exposure to stressors that reduce survival, dormancy, telomere maintenance, and self-renewal, thereby accelerating aging. While previous National Aeronautics and Space Administration (NASA) research revealed immune dysfunction in low-earth orbit (LEO), the impact of spaceflight on human HSPC aging had not been studied. To study HSPC aging, our NASA-supported Integrated Space Stem Cell Orbital Research (ISSCOR) team developed bone marrow niche nanobioreactors with lentiviral bicistronic fluorescent, ubiquitination-based cell-cycle indicator (FUCCI2BL) reporter for real-time HSPC tracking in artificial intelligence (AI)-driven CubeLabs. In month-long International Space Station (ISS) missions (SpX-24, SpX-25, SpX-26, and SpX-27) compared with ground controls, FUCCI2BL reporter, whole-genome and transcriptome sequencing, and cytokine arrays demonstrated cell-cycle, inflammatory cytokine, mitochondrial gene, human repetitive element, and apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3) deregulation together with clonal hematopoietic mutations. Furthermore, HSPC functionally organized multi-omics aging (HSPC-FOMA) analyses revealed reduced telomere maintenance, adenosine deaminase acting on RNA1 (ADAR1) p150 self-renewal gene expression, and replating capacity indicative of space-associated HSPC aging that may limit long-duration spaceflight.

Humans

Stromal Hedgehog Signaling Drives Segment-Specific Malignant Transformation of Gastrointestinal Stem Cells by Producing Bone Morphogenetic Protein Antagonists.

BACKGROUND & AIMS: Hedgehog signaling plays a complex role in epithelial-stromal interactions, but its effects on gastrointestinal stem cells mediated by heterogeneous stromal cell populations remain incompletely defined. Here, we investigate how stromal Hedgehog signaling regulates gastric stem cells and tumorigenesis in a segment-specific manner. METHODS: We genetically activated Hedgehog signaling in distinct stromal cell lineages using Col1a2-, Pdgfra-, Gli1-, Acta2-, and Prrx1-CreERT mouse lines, combined with lineage tracing, RNA sequencing, chromatin immunoprecipitation-quantitative polymerase chain reaction, and pharmacologic interventions. Human gastric cancer data from The Cancer Genome Atlas were also analyzed. RESULTS: We show that genetic activation of Hedgehog signaling in stromal cells marked by Col1a2, Pdgfra, or Gli1, but not by Acta2, induces tumorigenesis in the stomach and gastroesophageal junction, but not in the small or large intestine. Hedgehog signaling increases the expression of multiple bone morphogenetic protein antagonists in gastric but not colonic stromal cells, via Gli1-mediated transcription. These bone morphogenetic protein antagonists, in turn, activate Wnt/β-catenin signaling in gastric stem cells, driving their proliferation and initiating gastric cancer expressing CD44 and Sox9, but not Lgr5. Activating bone morphogenetic protein or inhibiting Wnt signaling blocks tumor initiation. Analysis of patient data from The Cancer Genome Atlas reveals elevated Hedgehog signaling in gastric cancers, which correlates with suppressed bone morphogenetic protein signaling. CONCLUSIONS: These findings uncover a gastrointestinal segment-specific oncogenic role for Hedgehog signaling in Col1a2+Acta2- stromal cells, mediated through the bone morphogenetic protein-Wnt-β-catenin axis.

BMP Antagonists

Bone-marrow-homing lipid nanoparticles for genome editing in diseased and malignant haematopoietic stem cells.

Therapeutic genome editing of haematopoietic stem cells (HSCs) would provide long-lasting treatments for multiple diseases. However, the in vivo delivery of genetic medicines to HSCs remains challenging, especially in diseased and malignant settings. Here we report on a series of bone-marrow-homing lipid nanoparticles that deliver mRNA to a broad group of at least 14 unique cell types in the bone marrow, including healthy and diseased HSCs, leukaemic stem cells, B cells, T cells, macrophages and leukaemia cells. CRISPR/Cas and base editing is achieved in a mouse model expressing human sickle cell disease phenotypes for potential foetal haemoglobin reactivation and conversion from sickle to non-sickle alleles. Bone-marrow-homing lipid nanoparticles were also able to achieve Cre-recombinase-mediated genetic deletion in bone-marrow-engrafted leukaemic stem cells and leukaemia cells. We show evidence that diverse cell types in the bone marrow niche can be edited using bone-marrow-homing lipid nanoparticles.

Animals

Mechanisms of Hematopoietic Stem Cell Aging and Emerging Rejuvenation Strategies.

Hematopoietic stem cell (HSCs) aging is a complex biological process driven by both cell-intrinsic alterations and extrinsic cues from the bone marrow niche. Understanding these mechanisms is critical for developing therapies against aging-related hematopoietic disorders. This review synthesizes recent advances in the molecular mechanisms underlying HSCs aging, including microenvironmental aging, genomic instability, epigenetic dysregulation, mitochondrial dysfunction, and aberrant nuclear mechanotransduction. We summarize that the functional decline of HSCs during aging drives a compensatory expansion of the phenotypically defined stem cell pool, leading to an aberrant increase in cell number. We also highlight aging-associated HSCs heterogeneity, including CD150high and P-selectin-positive subsets that enrich for myeloid-biased or functionally compromised HSCs states while emphasizing that surface phenotype alone may not fully indicate functional rejuvenation. Finally, we discuss emerging rejuvenation strategies-including targeting myeloid-biased HSCs, modulating inflammatory pathways, and implementing epigenetic or metabolic interventions-supported by cutting-edge technologies such as single-cell multi-omics, gene editing, and computational modeling. These approaches hold promise for counteracting age-related hematopoietic decline and restoring immune competence.

Humans