Cranial sutures are dynamic growth sites that balance bone growth with mesenchymal patency to accommodate cranial expansion during development. While intramembranous ossification has traditionally been considered the default mechanism of suture fusion, accumulating evidence demonstrates that endochondral pathways might also play a significant role under both physiological and pathological conditions. In this review, we contrast normal developmental ossification processes with premature fusion in craniosynostosis, integrating histological, molecular, and imaging data. We highlight the context-dependent nature of cranial suture biology, influenced by embryonic origin, local signalling gradients, and genetic perturbations. Recognizing divergent ossification mechanisms reframes our understanding of both normal and premature suture fusion and has clinical implications for mechanism-specific therapeutic strategies. Finally, we outline areas for future investigation, including high-resolution profiling of human sutures across developmental stages, to establish a normative framework for cranial suture biology and inform mechanism-driven regenerative approaches.

Cytotoxic chemotherapy primarily targets rapidly proliferating cancer cells but also depletes normal myeloid cells. The resulting cell loss triggers reactive myelopoiesis, a compensatory process in which hematopoietic stem and progenitor cells (HSPCs) in the bone marrow (BM) regenerate myeloid lineages. We previously showed that the alkylating agent cyclophosphamide (CTX) induces myelopoiesis leading to the expansion of immunosuppressive monocytes in mice. However, the molecular features and clinical relevance of these cells remain poorly understood. Here, we report the emergence of immunosuppressive monocytes in the peripheral blood of lymphoma patients receiving CTX-containing chemotherapy. To gain mechanistic insight into CTX-induced myelopoiesis, we performed single-cell RNA sequencing (scRNA-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) on BM monocytes from CTX-treated mice. These analyses revealed a heterogeneous monocyte population and demonstrated that CTX skews myelopoiesis toward the generation of neutrophil-like monocytes (NeuMo). Moreover, CTX-induced NeuMo cells, enriched within the CXCR4⁺CX3CR1⁻ monocyte subset, exhibited potent T-cell suppressive activity. Using the NeuMo gene signature, reanalysis of public scRNA-seq datasets identified a transcriptionally similar monocyte subset in chemotherapy-treated cancer patients. Collectively, our findings suggest that the expansion of NeuMo-like cells following chemotherapy represents a conserved immunoregulatory feedback mechanism with potential impact on tumor response to chemoimmunotherapy.

Aplastic anemia (AA) is a bone marrow failure disease characterized by immune-mediated destruction of hematopoietic stem and progenitor cells. Bone marrow adiposity represents a typical pathological manifestation observed in AA.

The replenishment of specialized cells depends on the activity of stem cells. Recent advances in stem cell research have shown that the germline stem cells (GSCs) in Drosophila melanogaster can increase their mitotic activity in response to mating. Here, we show that this ability to respond to mating is eliminated if the males are mutant for either of the ABC transporters, White (W), Brown (Bw) or Scarlet (St), which are known for their role in eye pigmentation and amine production. However, reducing the expression of w specifically from the germline cells also caused a failure to increase GSC mitotic activity upon mating, suggesting that w is required intrinsically in the stem cells. The w gene is a common genetic background for genetic experiments and frequently used as a control. Our findings underline the importance of careful experimental design and control choice.

The IgG1-based bispecific antibody tobemstomig (RO7247669) simultaneously targets and blocks PD-1 and LAG-3 expressed on activated T cells.

John Gurdon was a towering figure in developmental biology, respected and admired throughout the world. His discovery, made when he was a PhD student, that the nuclei of differentiated cells retain their pluripotency was fundamental to stem cell research and regenerative medicine, and his career-long loyalty to Xenopus laevis as an experimental organism was a constant inspiration to the field. Although Xenopus has sometimes been written off as a model organism in favour of other species, it is probably true that we have learned more about early vertebrate development from its use than from that of any other species. John received many awards for his research, including the Nobel Prize in Physiology or Medicine, the Albert Lasker Basic Medical Research Award, and both the Copley Medal and the Royal Medal of the Royal Society. He was also a significant contributor to UK science infrastructure and to academic life more broadly. Not only did he co-found the institute that now bears his name, but he also served as a Governor of the Wellcome Trust, and of Eton College, as Master of Magdalene College, University of Cambridge, as President of the British Society for Cell Biology and as Chair of The Company of Biologists, the publisher of this journal. Few biologists in the UK have achieved so much or been so influential.

We previously developed an induced pluripotent stem cell-based model to study an intronic region of KCNQ1 that represents the strongest association signal with type 2 diabetes in Indigenous Americans from Arizona. The current study builds on this model by using CRISPR/Cas9-edited isogenic cells that differ only by targeted type 2 diabetes single nucleotide polymorphisms in this intronic region. The effect of KCNQ1 type 2 diabetes single nucleotide polymorphisms on pancreatic β-cell development and the probable mechanism of this effect were previously unknown. The current study shows an effect on INS and H19 gene expression dynamics specifically during the endocrine progenitor stage of pancreatic islet development likely via an epigenomic effect on gene regulation resulting in generation of lower β-like cells. Individuals carrying KCNQ1 risk alleles for type 2 diabetes will likely benefit from therapeutics that increase pancreatic β-cell mass.

Measurable residual disease (MRD) is a key prognostic factor for outcomes following allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with acute myeloid leukemia. To enhance predictive performance, we developed a combined MRD assessment method that integrates the proportion of residual leukemic cells of ten-color multicolor flow cytometry (MFC) with peripheral blood WT1 mRNA expression.

Biomineralization refers to the process by which organisms form inorganic minerals, predominantly through the deposition of calcium phosphates. Calcium ions (Ca2+) serve not only as a fundamental component of the mineral phase but also as key signaling messengers that actively regulate the efficiency and progression of this process. The endoplasmic reticulum (ER) and mitochondria are two major organelles responsible for calcium ion storage and regulation within cells. Contact sites between mitochondria and ER, also called mitochondria-ER contacts (MERCs) or mitochondria-associated ER membranes (MAMs), have been identified as vital spots for calcium transfer. Existing research indicates that calcium ion transport from the ER to mitochondria occupies a pivotal position in biomineralization, but the relevance of MERC integrity in biomineralization is yet to be determined. This study revealed increased MERCs and calcium ion transport during mineralization in vivo and in vitro. Additionally, significantly impaired endoplasmic reticulum-mitochondrial interactions were observed in bone marrow mesenchymal stem cells (BMSCs) from ovariectomy-induced osteoporotic mice. Experimental enhancement of MERCs effectively increased mineralized nodule formation and alleviated ovariectomy-induced osteoporosis, whereas disruption of MERC integrity inhibited mineralization. Our findings indicate that endoplasmic reticulum-mitochondrial calcium ion transport plays a crucial role in biomineralization. This discovery provides a stronger theoretical foundation for elucidating the biomineralization process and may also identify novel therapeutic targets for related diseases.

The accuracy of crucial nuclear processes such as transcription, replication, and repair depends on the local composition of chromatin and the regulatory proteins that reside there. Understanding these DNA-protein interactions at the level of specific genomic loci has remained challenging due to technical limitations. Here, we introduce a method termed 'DNA O-MAP', which uses programmable peroxidase-conjugated oligonucleotide probes to biotinylate nearby proteins. We show that DNA O-MAP can be coupled with label-free or sample multiplexed quantitative proteomics, targeted chemical perturbations, and next-generation sequencing to quantify DNA-proximal proteins and DNA-DNA interactions at specific genomic loci in human and murine cells. Furthermore, we establish that DNA O-MAP is applicable to both repetitive and unique genomic loci of varying sizes, from kilobase HOX gene clusters to megabase alpha-satellite repeats, and that DNA O-MAP can measure proximal molecular effectors in a homolog-specific manner.

Normal mitochondrial function in stem cells is essential for effective bone regeneration, with mitochondrial complex IV (cytochrome c oxidase, CcO) playing a crucial role in sustaining electron transport chain activity and ATP synthesis. To address mitochondrial dysfunction associated with bone defects, we developed a dendritic mesoporous silica nanoparticle (DMSN)-based, CcO-mimetic nanozyme, named triphenylphosphonium (TPP)-DMSN-Fe/Cu. The nanozyme incorporated iron and copper single atoms to mimic the catalytic center of CcO and is modified with the mitochondria-targeting agent TPP. In vitro, TPP-DMSN-Fe/Cu nanozymes colocalized with mitochondria and enhanced mitochondrial function, effectively regulating cellular energy metabolism and promoting stem cell osteogenesis. In vivo, TPP-DMSN-Fe/Cu nanozymes resulted in significantly enhanced bone regeneration compared to the control, resulting in a 177% increase in bone volume and a 12% increase in mineral density at critical-sized bone defects in rats after 4 weeks of treatment. Taken together, these findings demonstrate that bioinspired, mitochondria-targeting TPP-DMSN-Fe/Cu nanozymes hold strong promise for accelerating bone regeneration via regulating cellular energy metabolism.

Extracellular vesicles (EVs) are promising vehicles for targeted therapeutic delivery, capable of encapsulating and transporting biomolecules to specific cells and tissues. Given that inflammation is central to many acute and chronic diseases, understanding EV biodistribution under inflammatory conditions is essential for therapeutic optimisation. This study examines how acute systemic inflammation influences EV biodistribution, clearance and plasma half-life, with a focus on the role of macrophages and their polarisation states. Using a lipopolysaccharide (LPS)-induced inflammation model in wild-type mice and bioluminescent and fluorescent labelling of EVs, we observed that inflammation extends the plasma half-life of EVs by over 600-fold within 2 h and 900-fold at 24 h post-administration, leading to significant enrichment in inflamed organs, particularly the liver and spleen. Enhanced accumulation in specific tissues translated to increased targeting of immune- and epithelial cells within those organs, with notable uptake by hepatocytes in the liver. To probe the mechanism, we profiled the EV protein corona, revealing inflammation-driven remodelling with enrichment of acute-phase proteins, complement factors and cytoskeletal regulators-linking corona composition to altered biodistribution. Yet, despite increased uptake and tissue accumulation, functional EV cargo delivery in vivo remained limited. These findings underscore the complex dynamics between EVs and immune cells under inflammatory conditions and provide critical insights for advancing EV-based therapies in chronic inflammatory diseases.

The repair of critical-sized cranial defects resulting from trauma, congenital malformations, or surgery remains a significant clinical challenge. Polyetheretherketone (PEEK) is a commonly used material for cranial defect repair in clinical practice. However, its application is severely limited by drawbacks such as poor structural adaptability, bioinertness, and insufficient osseointegration, which significantly compromise clinical outcomes. In this study, we biomimicked the structure and composition of natural bone to fabricate a biomimetic PEEK/hydroxyapatite (HA) scaffold via a 3D printing strategy. This scaffold exhibits a stochastic lattice structure and mechanical properties similar to natural bone, capable of sustained release of calcium and phosphate ions. An in vitro co-culture study with bone marrow mesenchymal stem cells (BMSCs) confirmed that the biomimetic scaffold promotes cell proliferation and enhances the expression of osteogenesis-related proteins and genes. In a rat model with a critical-sized cranial defect (8 mm diameter), the biomimetic PEEK/HA scaffold demonstrated excellent capability in inducing bone regeneration and promoting osseointegration. This research provides a viable strategy for the repair and functional reconstruction of clinical critical-sized cranial defects.

For several years, scientists have focused on studying mesenchymal stem cells because of their ability for self-regeneration, their potential for differentiation into multiple lineages (e.g., osteogenic, chondrogenic, and adipogenic cells), and their low immunogenicity and remarkable capacity to modulate the immune system. The importance of these cells ranges from preserving tissue health and repairing injured tissues in their nearby areas, to their use in scientific investigation for the treatment of neurodegenerative, autoimmune, and cardiovascular diseases. Despite the availability of various tissue sources, such as bone marrow and adipose tissue, their collection and handling may not always be easily achievable. However, dental tissues, such as the pulp and periodontal ligament, are relatively accessible supplies that do not require complex or stressful interventions for the patient. Here, we provide a detailed description of each step involved in the isolation and characterization of mesenchymal stem cells from the pulp and periodontal ligament using monoclonal antibodies ensuring a high level of effectiveness. In addition, we also describe a technique to generate the cellular presenescence state. © 2026 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Isolation of human periodontal ligament and dental pulp stem cells Support Protocol 1: Characterization of human periodontal ligament and dental pulp stem cells Support Protocol 2: Induction of presenescence of human periodontal ligament and dental pulp stem cells.

Generation of CAR macrophages from induced pluripotent stem cells(iPSCs) hold great potential for immunotherapy, particularly against T-cell malignancies which are challenging in CAR-T therapy. However, the tumoricidal activity of human iPSCs derived CAR-macrophages (iCAR-Ms) remains less extensively analyzed. Here, we generated human iCAR-Ms targeting CD5 for T-cell malignancy therapy. iCAR-Ms show up-regulation of immunity related functions as well as tumoricidal activity against different T malignant cells expressing CD5. However, the tumoricidal activity of iCAR-Ms is highly related to CD5 density on tumor cells and depends on high dose treatment in vivo. We further reveal that the tumor cells resisting iCAR-M killing show reversible CD5 loss mediated by iCAR-M trogocytosis. In contrast, the retrieved iCAR-Ms from tumor cell co-culture retained tumoricidal activity on new tumor cell expressing CD5. Thus, we identify trogocytosis as an important limiting factor on iCAR-Ms therapy, providing a rationale for developing enhanced CAR-M therapies.

The Par complex regulates cell polarity in diverse animal cells, but how it is restricted to a specific membrane domain remains unclear. The tumor suppressor Lethal giant larvae (Lgl) is thought to inhibit Par complex membrane binding, yet in metaphase Drosophila neural stem cells (NSCs), Lgl is cytoplasmic while the Par complex is apically polarized, raising the question of how Lgl controls Par localization when it is not on the membrane. Using live imaging, we found that Lgl and atypical Protein Kinase C (aPKC) exhibit tightly coordinated, opposing membrane dynamics: aPKC displaces Lgl at mitotic entry, while Lgl displaces aPKC at mitotic exit. In Lgl-depleted NSCs, aPKC is not fully cleared from the membrane after mitosis, and this residual aPKC persists into the subsequent division, disrupting Miranda polarization. Apical aPKC recruitment still occurs, indicating that Lgl is not required for Par polarization per se but for ensuring aPKC absence from the basal membrane before mitosis. These findings reveal a temporal mode of mutual antagonism between Lgl and the Par complex that may license proper asymmetric division.

Rapid and reliable identification of stem cells is a critical prerequisite for regenerative medicine and quality control during cell-based therapies. We report herein a lateral flow assay capable of detecting MSCs by dual-marker recognition using CD105 and CD29 surface antibodies. The biosensing platform relies on gold nanoparticle-conjugated CD29 antibodies as signal probes and immobilized CD105 antibodies as capture agents on the test line, allowing selective MSC recognition through sandwich-type immunocomplex formation with direct colorimetric readout. A distinct red band indicated the successful detection of MSCs, while a control line ensured assay validity and reliability. The developed LFA showed a naked eye detection limit as low as 600 cells within 15 min, which agreed with the qualitative data obtained via a smartphone-based Color Grab application. Notably, the device exhibited excellent stability with no cross-reactivity with non-target cells and successfully distinguished MSCs from their differentiated lineages. Besides this, the device retained stability for up to 28 days under room temperature. Further, MSC stemness was independently validated for CD105 and CD29 by flow cytometry (FACS), which requires a minimum of ≥10 000 cells per analysis. In comparison, the developed LFA provided reliable detection at substantially lower cell numbers, highlighting its significance as a low-input, rapid, and point-of-care alternative. This user-friendly platform represents a promising tool for rapid stemness assessment of MSCs towards their quality control and clinical translation in stem cell research and regenerative medicine applications.

Aplastic anemia (AA) is a rare bone marrow failure syndrome characterized by immune-mediated destruction of hematopoietic stem and progenitor cells (HSPCs). The contribution of the bone marrow microenvironment remains incompletely understood. We analyzed 29 bone marrow biopsies from patients with moderate (mAA), severe (sAA), and very severe AA (vsAA), along with 12 healthy controls and seven subcortical pseudohypocellular samples. Immunohistochemistry for nestin and CXCL12 was performed to quantify stromal niches. RNA sequencing was carried out to investigate immune and niche-related gene expression patterns. sAA patients exhibited a significantly increased number of nestin+ niches compared to mAA and controls. CXCL12+ niches showed no significant differences between groups. RNA sequencing revealed upregulation of immune response genes, as well as pathways related to interferon-gamma signaling, JAK-STAT3 activation, and antigen presentation. Downregulated genes and pathways pointed to impaired DNA repair, cell cycle regulation, and epigenetic stability. Our findings support a model in which AA pathogenesis is driven by both immune injury and compensatory, yet dysfunctional, stromal remodeling. These data underline the importance of the bone marrow microenvironment in AA.