Neural crest-derived cells offer valuable opportunities to dissect mechanisms of cell fate specification and differentiation and the underpinnings of cell type diversification over evolutionary time. Particularly useful for such analyses are pigment cells of ectothermic vertebrates that arise from neural crest cells or via latent neural crest-derived stem cells. Among these are white cells, leucophores, present in a variety of species that contribute to patterns on the body or ornamentation on the fins. To better understand developmental and evolutionary origins of these cells, we examined leucophores harboring deposits of yellow/orange carotenoids-xantholeucophores-of zebrafish and leucophores of white cloud minnow. We show that white phenotypes of both cell types require sepiapterin reductase and an accumulation of pale and colorless pteridines. We further demonstrate that xantholeucophores of zebrafish develop from yellow, sepiapterin-rich xanthophore-like cells and that this transition requires both gap junctional communication and the aquaglyceroporin/peroxiporin channel Aquaporin 3, revealing similarities and differences in differentiation and patterning compared to pigment cells on the body. These findings identify xantholeucophores of zebrafish and leucophores of white cloud minnow as distinct developmentally, genetically, and biochemically from other white cells of zebrafish-melanoleucophores-that develop directly from melanophores and depend on guanine crystals, as well as white cells of medaka fish and anemonefish. Our results highlight remarkable convergences and parallelisms in the acquisition of white cell phenotypes within and between phylogenetic lineages and identify this as a rich system for enquiries into the evolutionary individuation of novel cell types.

Ependymal cells in the adult ventricular-subventricular zone are increasingly recognized for functions extending beyond cerebrospinal fluid dynamics; however, their identity and functional specialization remain incompletely understood. While ependymal cells (EP) have been implicated in interactions with the stem cell niche and the vasculature, their role in repair processes following neural injury remains elusive. In this study, we employed region-specific single-cell transcriptomics of the subventricular zone (SVZ) and ipsilesional peri-infarct territory in mice to identify a distinct subpopulation of GFAP+ FOXF2+ EP that selectively expand within the SVZ after neural injury. Notably, these cells were absent from other brain regions. Immunohistochemical validation revealed characteristic ependymal features, including typical pinwheel architecture and expression of Foxj1 and β-catenin. Furthermore, the absence of the proliferation marker Ki67 and the resistance of this subpopulation to Ara-C-mediated ablation indicate that these cells do not possess proliferative properties. Conditional deletion of Foxf2 in GFAP+ cells led to impaired endothelial junction integrity and increased blood-brain barrier (BBB) permeability. In contrast, overexpression of Foxf2 via GFAP promoter-driven adeno-associated virus delivery enhanced vascular repair and facilitated functional recovery. Mechanistically, these GFAP+ FOXF2+ EP secrete exosomal DLL4, which was associated with enhanced NOTCH pathway activity and restoration of BBB function. While the mechanism linking this limited cell population to the broad reparative effect, particularly the complete signaling amplification cascade, remains to be fully elucidated, these findings identify a subset of EP that contributes to BBB repair.

This study aims to investigate the effect of exosomes derived from olfactory mucosa mesenchymal stem cells (OM-MSCs-Exo) on microglial polarization and its potential therapeutic role in Alzheimer's disease (AD). OM-MSCs-Exo were isolated and purified from the mice olfactory mucosa, followed by phenotypic characterization. Proteins transferred by OM-MSCs-Exo were screened using proteomic analysis. The AD model was established in microglial cells and mice with Aβ1-42. Immunofluorescence and biochemical assays were employed to assess the impact of OM-MSCs-Exo and its secreted protein FGFR1 on microglial polarization. Protein-protein interactions and immunoprecipitation were used to identify the target proteins of FGFR1 in microglial cells. Additionally, the effects of OM-MSCs-Exo-induced microglial polarization on neuronal inflammation and cognitive function in mice were evaluated. OM-MSCs-Exo were successfully isolated and purified. FGFR1 was significantly upregulated in OM-MSCs-Exo compared to OM-MSCs. Aβ1-42 induced M1 polarization and suppressed M2 polarization of microglia, which was reversed by OM-MSCs-Exo. FGFR1 overexpression in OM-MSCs-Exo further enhanced M2 polarization in microglial cells. Phospholipase C gamma 1 (PLCγ1) was identified as the target of FGFR1, and knocking down PLCγ1 reversed the effects of FGFR1-overexpressing OM-MSCs-Exo. OM-MSCs-Exo alleviated cognitive decline and neuroinflammation in AD mice, with FGFR1 overexpression further enhancing these effects. OM-MSCs-Exo promote M2 polarization of microglia in AD mice through the FGFR1/PLCγ1 pathway, alleviating neuronal inflammation and cognitive dysfunction.

Patients with relapsed/refractory T-cell acute lymphoblastic leukemia (R/R T-ALL) have very poor prognosis. CAR T-cell therapy is being explored in these patients with encouraging results. Specifically, CD1a-directed CAR T-cells are being explored in clinical trials to treat cortical T-ALL (CD1a+), but there are no data on outcome in this subgroup of patients before this therapy. This retrospective, observational study aimed to describe the characteristics and outcomes of patients with R/R CD1a + T-ALL. We included pediatric and adult patients diagnosed with R/R CD1a + T-ALL in 25 sites of Spain between March 2006 and May 2022. The primary outcome of the study was overall survival (OS). Forty-three patients, 28 adults and 15 children, with R/R CD1a + T-ALL were included. Median (range) age at inclusion was 24 years (5–57), and 82.5% were male. After a median (range) follow-up of 7.0 years (5.1–13.6), 6 (14.0%) patients were alive and in complete remission (CR) and 37 (86.0%) had died. Five-year OS was 16% (95% CI; 7–29%). Bone marrow relapse, an interval < 12 months between first CR and relapse, and lack of allogeneic hematopoietic stem cell transplantation during salvage treatment were associated with worse OS. Our results confirm that patients with R/R CD1a + T-ALL have a very poor prognosis, highlighting the need for new treatment alternatives in these patients.

Standard preclinical human tumor models lack a human tumor stroma. However, as stroma contributes to therapeutic resistance, the lack of human stroma may make current models less stringent for testing new therapies. To address this, using patient-derived tumor cells, patient-derived cancer-associated mesenchymal stem/progenitor cells, and human endothelial cells, we created a human stroma-patient-derived xenograft (HS-PDX) tumor model. HS-PDX, compared to the standard PDX model, demonstrates greater resistance to targeted therapy and chemotherapy and better reflect patient response to therapy. Furthermore, HS-PDX can be grown in mice with humanized bone marrow to create humanized immune stroma patient-derived xenograft (HIS-PDX) models. The HIS-PDX model contains human connective tissues, vascular and immune cell infiltrates. RNA sequencing analysis demonstrated a 94-96% correlation with primary human tumor. Using this model, we demonstrate the impact of human tumor stroma on recruitment of TAMs and tumor immune exclusion to impact to response to immunologic therapy. We show an immunosuppressive role for human tumor stroma and that this model can be used to identify immunotherapeutic combinations to overcome stroma-mediated immunosuppression. Combined, our data confirm a critical role for human stroma in therapeutic response and indicate that HIS-PDX can be an important tool for preclinical drug testing.

Autologous hematopoietic cell transplantation (ASCT) is a reasonable consolidation therapy for eligible patients with chemosensitive relapsed central nervous system lymphoma (CNSL) who have achieved complete remission (CR) and maintained the CR. Chimeric antigen receptor T-cell (CAR-T) therapy is an effective treatment option for patients with relapsed CNSL, although evidence on outcomes in patients who achieve CR is limited.

The differentiation of human embryonic stem cells (hESCs) into primordial germ cell-like cells (PGC-LCs) provides a robust in vitro model to study human germline specification. Here, we present a simple, reproducible, and cost-effective protocol for generating DEAD-box helicase 4 (DDX4)/VASA and Deleted in Azoospermia-Like (DAZL)-positive PGC-LCs from hESCs using a combination of bone morphogenetic protein 4 (BMP4) and conditioned medium (CM) derived from Stage-Specific Embryonic Antigen-4 (SSEA4)-positive human amniotic fluid stem cells (hAFSC-4). Importantly, unlike conventional protocols that rely on embryoid body formation, our method employs adherent cultures for germ cell differentiation. This approach enhances reproducibility by avoiding the spontaneous and stochastic variability inherent to embryoid body formation. This protocol provides a reproducible and physiologically relevant platform for studying human germ cell development in vitro.

Glioblastoma (GBM) is the most malignant primary brain tumor. The presence of glioma stem/initiating cells (GICs) is known to cause strong treatment resistance; therefore, GICs are a major target for GBM therapy, although there are no therapies targeting GICs clinically. To identify novel treatments for GBMs, we performed drug repositioning screening using GICs and identified T-type calcium channel blocker lomerizine-a migraine prophylactic drug. Lomerizine inhibited proliferation, migration, invasion, and cell cycle progression and induced apoptosis in GICs and differentiated glioma cells. Lomerizine had antitumor effects by inactivating STAT3 in all cell lines. Furthermore, lomerizine also dephosphorylated AKT and ERK only in GICs and strong tumor suppressive ability. Lomerizine also reduced tumor volume and prolonged overall survival in vivo. Based on our data from in vitro and in vivo experiments, lomerizine has potential as a novel GBM therapeutic agent targeting against both GICs and differentiated glioma cells and could benefit for GBM patients.

Although 5-aminolevulinic acid (5-ALA) has shown potential for hair growth in previous studies, the molecular mechanisms remain unclear. In this study, we investigated the combined effect of 5-ALA with ferric ammonium citrate (FAC) in human hair follicle models. At low micromolar concentrations, 5-ALA/FAC treatment increased proliferation of dermal papilla cells, keratinocytes, fibroblasts, and adipose-derived stem cells, and rapidly activated ERK and AKT signaling. This treatment also upregulated hair-inductive genes and restored their suppression by dihydrotestosterone or oxidative stress. In functional assays, 5-ALA/FAC treatment induced hair follicle-like structures in reconstituted skin and enhanced hair shaft elongation in ex vivo organ culture. These findings indicate that 5-ALA/FAC treatment stimulates human hair follicle growth and support its potential as a therapeutic candidate for hair loss.

Glioblastoma (GBM) is the most malignant primary central nervous system tumor in adults, with strong invasiveness, high recurrence, and poor prognosis. Natural killer (NK) cells, innate immune cells that eliminate glioma stem cells without MHC matching, show promise for GBM immunotherapy, but their efficacy is limited by GBM's immunosuppressive tumor microenvironment (TME), especially via protein post-translational modifications (PTMs). This review summarizes seven key PTMs' (phosphorylation, acetylation, glycosylation, methylation, ubiquitination, SUMOylation, lactylation) dual regulation on NK cell therapy: physiological PTMs enhance NK cytotoxicity, targeting, and persistence; aberrant PTMs block NK activation, induce exhaustion, and promote GBM immune escape. It also analyzes bottlenecks (insufficient NK activity/persistence, GBM's PTM-mediated escape) and breakthroughs (PTM-targeted small molecules like TAK-981, CRISPR-edited NK cells, combination therapies). Future directions include BBB precision delivery, PTM-guided personalized therapy, and PTM crosstalk research, aiming to advance NK therapy's clinical translation for GBM.

Although studies support disrupted bone remodelling within geriatric populations, mid-life changes are understudied. To investigate this, we performed bone marrow transplantation assays using either 8- or 40-week-old mice. Micro-CT analyses of lethally irradiated 8-week-old mice transplanted with 40-week-old bone marrow exhibited increased mid-shaft femoral cortical bone mass and thickness. Intensive bone marrow regeneration mirrors hematopoietic development in that erythro-myeloid progenitors (EMPs) first expand to support blood production before definitive hematopoietic stem cell (HSC) production. We hypothesized that reduced HSC capacity of 40-week-old bone marrow and compensatory expansion of EMPs may facilitate gains in cortical bone. Flow cytometry analyses revealed greater EMP to HSC ratios when mice were reconstituted with increasing percentages of middle-aged bone marrow. To identify cell types mediating these effects, we performed comparative scRNA-Seq analyses and identified CD11B+CD36+ myeloid cells exhibiting enriched expression of bone anabolic cytokines. Elevated levels of Wnt ligands, especially Wnt6, characterized these cells. In lineage tracing assays, CD11B+CD36+ cells were donor-derived myeloid cells. In functional assays, we demonstrate that soluble factors produced by CD11B+CD36+ cells enhance osteogenesis. Moreover, CD11B/CD36/Wnt6 exquisitely mark anabolic macrophages within human bone marrow. These findings reveal a myeloid population present during midlife that enhances cortical bone.

Adipose tissue is increasingly recognized as an important component of the tumor microenvironment of colorectal cancer (CRC) and actively contributes to the progression of the disease. Adipose stem cells (ASCs), one of its key constituents, can interact with cancer cells and contribute to tumorigenic processes. However, there is a poor understanding of the underlying basis of ASC-mediated support in the progression of CRC.

Enhanced P-TEFb activity is thought to promote cell proliferation by increasing the transcriptional output of RNA polymerase II. The 7SK snRNP complex, which contains LARP7 and HEXIM1, sequesters and inhibits most cellular P-TEFb to prevent premature transcription elongation. Paradoxically, instead of exerting overgrowth effects, biallelic inactivation of LARP7 is linked to Alazami syndrome, a human neurodevelopmental disorder characterized by growth restriction and cognitive impairment. Here, we report that conditional ablation of either Larp7 or Hexim1 in the murine brain reduces the size and impairs the function of the hippocampal dentate gyrus during the neonatal period. Functional analyses reveal that increased P-TEFb activity enhances self-renewal transcriptional programs in transit-amplifying neuronal progenitor cells to limit neurogenesis in developing dentate gyri. These results demonstrate that dysregulated subtissular stem cell dynamics can reconcile increased P-TEFb activity with reduced organ growth, and suggest a translational opportunity for repurposing P-TEFb inhibitors to treat medical conditions affecting dentate gyrus size and function.

CRISPR/Cas9 technology enables efficient gene editing in mice, but its reliance on non-homologous end joining often leads to unpredictable and mosaic mutations in founder (F0) animals. Here, we present a hybrid genome editing strategy that combines in silico prediction software with in vitro validation using mouse embryonic stem cells (mESCs). Although the software was trained on mESC datasets, actual editing outcomes in mESCs more accurately reflected mutation patterns observed in blastocysts and post-implantation embryos. Using this information to develop an integrated pipeline, we pre-selected guide RNAs (gRNAs) predicted to promote microhomology-mediated end joining (MMEJ)-dominant repair and validated them in mESCs prior to embryo injection. Applied to the Tyr and Fgf10 genes, this approach enabled efficient generation of F0 mice with highly uniform genotypes. Our strategy enhances the predictability and reproducibility of CRISPR-based genome editing in mice and may help reduce animal usage in gene editing studies.

RNA-binding proteins play critical roles in RNA processing and are aberrantly expressed in colorectal cancer (CRC). Through comprehensive analysis of multiple gene expression datasets (GSE20916, GSE18105, GSE21510, TCGA-COAD and TCGA-READ), NCBP2 was identified as a potential tumorigenic gene in CRC. NCBP2 expression was significantly elevated in CRC tissues, correlated with tumour invasion and metastasis, and associated with poor patient survival outcomes. Furthermore, overexpression of NCBP2 in CRC cells was shown to increase cell proliferation, migration, and tumour invasion in both in vitro and in vivo models. Mechanistically, the NCBP2 protein stabilised LIPG mRNA via direct binding to the m7G motif in the 5'-cap structure of LIPG mRNA, thereby increasing LIPG expression. Additionally, NCBP2 promoted lipid droplet accumulation in CRC cells in a LIPG-dependent manner. These findings collectively suggest that the NCBP2-LIPG-lipid droplet axis represents a novel mechanism underlying CRC progression and metastasis, providing a promising therapeutic target for CRC treatment.

Helicobacter pylori (HP) is a major cause of gastritis, yet the epithelial mechanisms linking infection-induced stress to mast cell and Treg responses remain poorly defined.

The spinal cord injury (SCI) microenvironment undergoes significant biochemical changes that influence the behavior of endogenous neural stem/progenitor cells (NSPCs), including elevated glucocorticoid levels. Here, we investigate the effects of glucocorticoids on NSPCs in the adult mouse spinal cord. Adult spinal cord NSPCs express glucocorticoid receptors but not mineralocorticoid receptors. Glucocorticoid exposure significantly inhibits NSPC proliferation, neurosphere formation, and differentiation through glucocorticoid receptor activation. In a traumatic SCI mouse model, treatment with the glucocorticoid receptor inhibitor CORT125281 improves motor function and increases the number of NSPCs at the injury site. Flow cytometry and RNA sequencing analyses show that glucocorticoids induce NSPC G0/G1 cell-cycle arrest through activation of the p53 signaling pathway, accompanied by increased expression of the cell-cycle regulators p15, p18, and p27. These findings suggest that glucocorticoid elevation after SCI suppresses endogenous NSPC proliferation via glucocorticoid receptor activation, and targeting this pathway may represent a potential therapeutic strategy to enhance recovery after SCI.

A hallmark of mammals is a diploid genome. Despite constraints from dosage compensation and imprinting, haploid embryonic stem cells can be established. However, rapid diploidization is observed in such cultures from mice, rats, and humans, limiting their use and indicating counterselection of a haploid genome. Here, we use metabolic profiling to discover that diploidization is triggered by an imbalance that arises from a smaller cytoplasmic volume and increased mitochondrial density. Reduced respiration causes a change in redox potential, leading to increased NADPH. Conversely, we demonstrate that NADPH oxidation in the mitochondria is sufficient to stabilize the haploid genome. We further show that the redox change leads to reduced AURORA kinase activation on chromosomes, connecting metabolic state to mitotic regulation. Our data, therefore, identify a mitochondrial metabolic imbalance as the root cause of diploidization and connect redox dysregulation to karyotypic instability.