The cellular, immunogenetic, and antigenic factors affecting the breadth of viral antigen variants recognized by human antibody responses are poorly defined. We developed highly multiplexed panels of DNA-tagged SARS-CoV-2 antigens from up to 20 viral variants to label and sort 6,262 antigen-binding circulating B cells from previously naive mRNA vaccinees or infected patients, and from deceased organ donor lymphoid tissues, to enable antigen receptor and transcriptome sequencing. Atypical B cells and a subset of class-switched memory cells with evidence of recent germinal center exposure were enriched for antigen binding. In contrast to atypical B cells, post-germinal center B cells showed progressively increasing variant binding breadth and somatic hypermutation over time. Vaccination, compared with infection, preferentially stimulated B cells expressing antibodies with inherently high antigen-binding breadth. This large-scale analysis reveals key determinants of antigen-binding breadth, critical for understanding responses to viral infection and guiding vaccine development against rapidly mutating viruses.

Regulatory T cells (Tregs), winners of the 2025 Nobel Prize in Physiology or Medicine, emerged as an unsung giant of peripheral immune tolerance after allogeneic hematopoietic stem cell transplantation (allo-HSCT). These cells exert influence across four interconnected immunological axes encompassing graft-versus-leukemia (GVL), graft-versus-host disease (GVHD), relapse, and viral infection. This correspondence highlights key advancements in Treg-based interventions in allo-HSCT, ranging from basic research to clinical applications, as presented at the ASH 2025 Annual Meeting. Accordingly, Tregs are used as GVHD prophylaxis via the Orca-T platform and as a therapeutic strategy for steroid-refractory (SR)-GVHD patients. Experimental studies further pave the way to address existing limitations toward next-generation Treg-based cell therapy in allo-HSCT.

Reprogramming tumor-associated macrophages (TAMs) from the pro-tumoral M2-like state to the immunostimulatory M1-like phenotype has emerged as a promising strategy for tumor therapy. However, most M2-like TAMs are preferentially located in hypoxic regions of the tumor, which are poorly accessible to many advanced drug delivery systems, posing a significant challenge to effective TAM reprogramming. Here, leveraging the tropism of facultative anaerobic bacteria to localize and propagate in the hypoxic tumor, an optogenetically engineered Escherichia coli Nissle 1917 strain conjugated with murine STING agonist (EcNflaB@UPD) was developed for cancer-specific immunotherapy. Upon near-infrared light illumination, the blue and UV emissions from upconversion nanoparticles (UCNPs) simultaneously activate the expression of Toll-like receptor (TLR) agonist, flaB, from EcNflaB, and the release of photocaged murine STING agonist, DMXAA, respectively. This spatiotemporally synchronized dual release ensures co-localized STING and TLR5 agonists inside the hypoxic niche, repolarizing TAMs from the M2 to the M1 phenotype via synergistic TLR5-MAPK1-NF-κB and STING-NF-κB signaling. The polarization of TAMs enhances their antigen-presenting capacity and, more importantly, activates the cytotoxic, stem-like and memory CD8+ T cells responses. This subsequently inhibits tumor growth, relapse, and metastasis in the murine 4T1 tumor model. Collectively, our work introduces the bacteria-based system that uses near-infrared light to dual-release immunotherapeutics for systemic anti-tumor immunity, opening new avenues for precise and effective cancer immunotherapy.

Reprogrammable Adenosine Deaminase Acting on RNA (ADAR) Sensors (RADARS) control RNA translation in mammalian cells, allowing for noninvasive sensing or perturbation of specific cell types based on transcriptional signatures. Upon base-pairing between a target RNA and a sensor RNA, RADARS leverages ADAR to edit a premature stop codon upstream of a gene of interest, thereby releasing translation of the desired cargo. These design principles enable sequence programmability, allowing RADARS to adapt more easily to new contexts than existing tools for targeting cell types. We describe a detailed protocol for performing experiments with RADARS, including designing, cloning and validating RADARS constructs targeting a transcript of interest. RADARS guide sequences can be designed with an intuitive web interface and cloned into existing constructs for downstream applications including imaging, sorting and sequencing. We outline recommendations for cargo choice, sensor design and ADAR system selection, enabling users to choose the best workflow depending on the desired application. Beginning with sensor design, the selection of top-performing RADARS guides can be completed in ~2 weeks, followed by a desired use case. Convenient engineering and application of RADARS for various applications enable the design and execution of various cell-targeting experiments.

Growing evidence implicates early metabolic dysfunctions in retinal ganglion cells (RGCs) as a contributor to both high- and normal-tension glaucoma, yet no approved therapy directly protects RGCs to preserve vision. We aimed at identifying a safe, druggable neuroprotective strategy that restores RGC metabolic homeostasis for glaucoma therapy.

Successful autologous stem cell transplantation (ASCT) in newly diagnosed multiple myeloma (NDMM) patients relies on the efficient mobilization of hematopoietic stem cells following induction therapy. While the efficacy of etoposide for stem cell mobilization has been demonstrated in numerous studies, a randomized comparison of the efficacy of cyclophosphamide versus etoposide has previously been lacking. This randomized, open-label, multicenter trial enrolled NDMM patients eligible for ASCT. The inclusion criteria were patients with a diagnosis of NDMM who required stem cell mobilization prior to ASCT. Patients were randomly assigned to receive either high-dose etoposide (VP16; 1.2 g/m2) or high-dose cyclophosphamide (CTX; 3.0 g/m2) before mobilization. Granulocyte colony-stimulating factor (G-CSF) was administered after chemotherapy to promote stem cell mobilization. The primary endpoint was the proportion of patients achieving CD34 + cell counts ≥ 2 × 10⁶/kg and ≥ 5 × 10⁶/kg. A total of 62 patients were enrolled, with 31 patients in each group. The VP16 group significantly outperformed the CTX group in CD34 + cell collection across all thresholds: ≥2 × 10⁶/kg (100% vs. 77%, p = 0.011), ≥ 5 × 10⁶/kg (90% vs. 55%, p = 0.002), and ≥ 8 × 10⁶/kg (71% vs. 32.3%, p = 0.023). The VP16 group also showed superior success rates in the first apheresis session and achieved higher CD34 + percentages in the collection. Additionally, the VP16 group required fewer apheresis sessions, fewer platelet transfusions, and experienced less nausea during the mobilization period. High-dose etoposide (1.2 g/m2) demonstrated superior efficacy and safety compared to high-dose cyclophosphamide (3.0 g/m2) for stem cell mobilization in NDMM patients. Based on these findings, etoposide may be considered a more effective and safer option for stem cell mobilization in clinical practice.The clinical trial was registered on 24/08/2022 (clinical trial identifier NCT05517213).

In this study, we demonstrate that cytoskeletal state at the onset of directed differentiation impacts the exit of human pluripotent stem cells (hPSCs) from pluripotency and downstream lineage specification. In particular, depolymerizing F-actin with latrunculin A (latA) during the first 24 h of definitive endoderm formation facilitates efficient loss of pluripotency and alters Activin/Nodal, BMP, c-Jun, and WNT signaling dynamics. These signaling changes influence downstream patterning of the gut tube, leading to improved pancreatic progenitor identity and decreased expression of markers associated with other endodermal lineages. Continued differentiation generates islets containing a higher percentage of β cells that exhibit improved maturation, insulin secretion, and ability to reverse hyperglycemia. Furthermore, this latA treatment reduces enterochromaffin cells in the final cell population and corrects differentiations from hPSC lines that otherwise fail to consistently produce pancreatic islets, highlighting the importance of cytoskeletal signaling at the onset of directed differentiation.

Glioblastoma (GBM) is an aggressive primary brain tumor marked by a poor prognosis and limited effectiveness of current therapies, which are often accompanied by substantial recurrence rates. To address this challenge, we developed BM03, an engineered mesenchymal stem cell (MSC) line specifically designed for glioblastoma therapy. BM03 is structured to enhance migration to GBM sites and deliver targeted, multimodal gene-based therapies.

Compared to the general population, individuals with Neurofibromatosis Type 1 have a 50-fold higher risk of developing a high-grade glioma (HGG) in their lifetime. Despite improved understanding of the molecular and cellular drivers of these neoplasms, we have yet to translate this knowledge into therapies that improve overall survival. One limitation has been the paucity of in vivo models for drug testing within this population. We generated 3 distinct glioma stem cell lines from high-grade gliomas arising in mice with Nf1 and Trp53 mutations in cis (NPcis) and characterized the allografts resulting from one Nf1-glioma stem cell line (Nf1-HGG17) by single cell and single nuclear RNA-seq. Because our cell lines are grown in stem cell media, there is an inherent reduction of the differentiation states present in primary HGG, with only oligodendrocyte precursor-like and neural-like cells identified. However, orthotopic allografts of Nf1-HGG17 regained the other differentiation states typically observed in HGG and GBM (neuronal progenitor cell-like and astrocyte-like). About half of neoplastic cells cluster separately from these classical groups and highly express genes of the antigen presentation machinery, including Cd74, which we also observed in patient samples. Notably, heterozygosity of Nf1 within the tumor microenvironment does not cause marked changes in the immune tumor microenvironment, gene expression, or differentiation states of neoplastic cells. These data indicate that allografted HGG lines from NPcis mice are an effective model of NF1-HGG, mimicking the complexity observed in human HGG, that can be used for larger scale in vivo drug screening and evaluation.

Wound healing is complex, and hard-to-heal (chronic) wounds pose significant treatment challenges, especially in adults. Micrografts (MGs) are emerging as a promising treatment for wounds refractory to conventional approaches. MG involves transplanting a stem cell suspension to the wound to promote healing. Scientific studies on MG are increasing; however, a systematic review is needed for a comprehensive understanding of its efficacy.

The amygdala paralaminar nuclei (PL) contain immature excitatory neurons that develop on a delayed timeline from birth to adulthood and are more prominent in the amygdala of humans and other primates than in rodents. Whether this expansion is linked to brain complexity or is a feature of primates is unknown. We sought to identify the PL in the ferret (Mustela putorius furo), a small, gyrencephalic mammal that does not belong to the primate order. Here, we show that the amygdala of juvenile (P30-P67) and adult ferrets (>1 year) also contains a collection of immature excitatory neurons that express doublecortin (Dcx) and polysialylated neural cell adhesion molecule (Psa-Ncam). Similar to humans and mice, these immature neurons express Tbr1 and CoupTFII, but not FoxP2, which labels neighboring clusters of GABAergic cells in the intercalated nuclei. Ferret PL neurons extend into the ventral basolateral amygdala (BLA) and appear either in dense clusters surrounded by astroglia or as individual cells, and each subpopulation contains neurons with migratory morphology. This expansion of PL neurons into the amygdala is similar to what is seen in humans, but unlike in mice, where PL neurons are infrequent in the BLA. We compared these findings to the marmoset (Callithrix jacchus), a lissencephalic non-human primate, and the swine (Sus scrofa domesticus), a gyrencephalic mammal, and found immature neurons extending into the amygdala in both. Our study identifies the PL region of the ferret amygdala, which contains immature neurons with migratory features in juveniles and adults. Cross-species comparisons indicate that the expansion of PL neurons into the amygdala seen in primates with both high and low gyrencephalic indices has also occurred in species with gyrencephalic brains from different orders.

Chromosome karyotyping, particularly G-banding, is a fundamental diagnostic and prognostic tool for hematological malignancies, providing a genome-wide view of large-scale numerical and structural chromosomal abnormalities. Its clinical utility is paramount for disease classification, risk stratification, and the evaluation of hematopoietic stem cell transplantation (HSCT) across diseases such as acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), multiple myeloma (MM), and myelodysplastic syndromes (MDS). However, clinical challenges including low resolution and culture failure necessitate complementary advanced techniques. Fluorescence in situ hybridization (FISH) targets specific aberrations in non-dividing cells, while array comparative genomic hybridization (aCGH) and single-nucleotide polymorphism (SNP) arrays offer higher resolution for detecting cryptic copy number variations (CNVs) and copy-neutral loss of heterozygosity (CN-LOH). Furthermore, the modern diagnostic standard has evolved into a multi-omics approach that integrates morphology, flow cytometry, karyotyping, and next-generation sequencing (NGS). This comprehensive workflow significantly enhances diagnostic accuracy, refines risk stratification, and informs personalized therapeutic strategies. Clinically, karyotyping is essential for assessing cytogenetic remission, though it is less sensitive for minimal residual disease (MRD) detection than molecular methods. As emerging technologies such as optical genome mapping (OGM) demonstrate the potential to streamline these workflows, karyotyping continues to evolve, solidifying its indispensable role in the comprehensive management of hematologic cancers.

Acute Myeloid Leukemia (AML) remains a therapeutic challenge due to immune evasion and relapse. T-cell immunoglobulin and mucin domain-containing-3 (TIM-3) is an immune checkpoint receptor aberrantly expressed on immune cells and leukemic stem cells (LSCs) in AML. Biologically, TIM-3 predominantly mediates deleterious effects, promoting T-cell/NK dysfunction and supporting LSC self-renewal, but this pathogenic expression also makes TIM-3 a therapeutically actionable target. This narrative review synthesizes current preclinical and clinical evidence on the role of TIM-3 in AML. We examined its structure, signaling pathways, and dual functions in promoting immune suppression and LSC self-renewal. A comprehensive analysis of ongoing therapeutic strategies, including monoclonal antibodies and cellular therapies, was conducted. Relevant literature was identified through searches of PubMed, Scopus, and Web of Science databases, with a focus on recently published studies. TIM-3 contributes to immune dysregulation by inducing T-cell exhaustion, impairing NK cell cytotoxicity, and enhancing immunosuppressive myeloid cells. Concurrently, its expression on LSCs drives leukemogenesis through autocrine signaling loops involving Galectin-9 and the β-catenin pathway. Preclinical studies show that TIM-3 blockade reduces leukemic stem-cell frequency and impairs LSC reconstitution in xenograft models, and can reinvigorate anti-leukemic immunity in experimental systems; however, these findings are preclinical and have not yet translated into consistent, randomized clinical benefit in human trials, underscoring the need for biomarker-guided and combination approaches in clinical development (Kikushige et al. Cell Stem Cell 17(3):341–352, 2015; Kikushige et al. Cell Stem Cell7(6):708–717, 2010; Zeidan et al. Lancet Haematol11(1):e38–e50, 2024). Clinically, the anti-TIM-3 antibody sabatolimab showed a tolerable safety profile and preliminary signals of activity when combined with hypomethylating agents; however, randomized phase II data did not demonstrate statistically significant improvements in the primary endpoints (complete response rate and progression-free survival), and the development program has since been re-evaluated in light of these results. TIM-3 also shows promise as a diagnostic and prognostic biomarker. TIM-3 plays an important and multifaceted role in AML pathogenesis, with evidence supporting both immune-regulatory functions and roles in leukemic stem cell biology; however, definitive proof that TIM-3 is essential for LSC maintenance across all AML subtypes requires additional genetic and functional validation. Targeting TIM-3 remains a biologically compelling strategy to address immune suppression and LSC biology in AML, but definitive clinical benefit has not been established in randomized studies to date; further investigation, especially in biomarker-enriched, low-tumor-burden settings and rational combinations, is required to define its clinical role.

Using the well-studied two-stage model of skin carcinogenesis, the first transgenic mouse with targeted expression of a polyamine metabolic enzyme was generated 30 years ago. Ornithine decarboxylase (ODC), a key regulating enzyme of polyamine biosynthesis, was constitutively expressed in the outer root sheath cells of hair follicles near the bulge stem cell niche using a keratin 6 promoter in K6/ODC mice. Early studies using K6/ODC mice demonstrated that polyamines play an essential role in the early promotional phase of skin tumorigenesis. Treatment with inhibitors of ODC activity blocked the formation of skin tumors and caused the rapid regression of existing tumors. We review how use of the K6/ODC mouse has shown that elevated polyamines in epithelial cells stimulate proliferation and invasiveness, recruit stem cells, alter chromatin remodeling and cell signaling leading to metabolic reprogramming, increase vascularization, activate underlying fibroblasts, and have powerful effects on immune cell function, all contributing to the development and progression of tumors.

Post-transcriptional regulation is pivotal for cellular differentiation, yet how translationally silent mRNAs are selectively reactivated remains elusive. Here, we identify the MEX3D-HIP1 (MX-H) pathway and its associated organelle, the MEX3D-associated lysosomal vesicle (MXLV), as a shared system governing mRNA activation during spermiogenesis. Our data support a model in which MEX3D acts as an RNA-associated E3 ligase that selectively promotes ubiquitination of RBPs within RBP-mRNA complexes. This ubiquitination signal recruits HIP1, triggering the formation of MXLV, an autophagic vesicle that degrades translationally silent mRNP complexes. Genetic ablation of MX-H components in male germ cells disrupts spermiogenesis, leading to the accumulation of mRNP aggregates and male infertility. Intriguingly, we discovered that this germline-restricted pathway is aberrantly activated in gastric cancer cells, where MXLV biogenesis promotes tumor progression. The strict restriction of MXLV to male germ cells under physiological conditions may provide a unique therapeutic window, suggesting that targeting this pathway could suppress tumor progression while minimizing adverse effects on normal physiological functions. Our work establishes MXLV as a specialized vesicular structure essential for cellular remodeling during development and reveals how a germline-specific membrane trafficking system is co-opted in pathological proteome remodeling in gastric cancer.

How tumors manipulate neural circuits to evade immunity is unclear. In a recent study, Wei et al. reveal, in lung adenocarcinoma, a vagal sensory-brain stem sympathetic circuit that suppresses macrophages and CD8+ T cells via β2-adrenergic signaling. Disrupting this axis restores antitumor immunity, nominating β-blockers and neural modulation as promising therapies.

The molecular mechanisms linking immune cell signaling to osteoclastogenesis remain incompletely defined. Here, we identify an Annexin A1 (AnxA1)-Dectin-1 axis as a key driver of osteoclast differentiation. Dectin-1 (CLEC7A), a myeloid C-type lectin receptor best known for β-glucan recognition, is shown to bind the endogenous ligand AnxA1 on pre-osteoclasts, thereby promoting their maturation. In Dectin-1 deficient mice, reduced osteoclast numbers resulted in increased bone volume, whereas β-glucan-induced Dectin-1 activation enhanced osteoclastogenesis. Within the bone marrow niche, AnxA1 was abundantly expressed on B220+ B cells, and γ-irradiation markedly increased its surface translocation both in vitro and in vivo. γ-irradiated B220+ B cells exhibited strong Dectin-1 binding capacity and robustly stimulated osteoclast differentiation in a Dectin-1-dependent manner. These findings establish the AnxA1-Dectin-1 interaction as a critical immune-skeletal communication pathway, revealing a mechanism by which radiation exposed immune cells can accelerate bone resorption. Targeting this axis offers a potential strategy to mitigate radiation-induced bone degradation and preserve skeletal homeostasis.