Relapsed/refractory RUNX1::RUNX1T1-positive acute myeloid leukemia remains a therapeutic challenge due to high relapse rates post-allogeneic hematopoietic stem cell transplantation. Preclinical evidence suggests that RUNX1::RUNX1T1 fusion proteins sensitize cells to poly ADP-ribose polymerase inhibitors by suppressing homologous recombination repair. This study explores the safety and efficacy of a novel conditioning regimen incorporating olaparib (a PARPi) for relapsed/refractory RUNX1::RUNX1T1+ AML patients undergoing allo-HSCT.

Forkhead Box A2 (FOXA2) is a transcription factor essential for endodermal development and the formation and function of several metabolic organs, including the liver and pancreas. Within the pancreatic lineage, FOXA2 plays a crucial role in orchestrating islet development, maintaining β-cell identity, and regulating genes central to glucose sensing and insulin secretion. This review provides a comprehensive overview of FOXA2's dual role in both developmental and mature stages of pancreatic islets, highlighting its function as a gatekeeper of lineage specification and metabolic homeostasis. We describe FOXA2's dynamic expression patterns during embryogenesis, its regulatory interactions with other key transcription factors, such as PDX1 and NKX6.1, and its influence on chromatin accessibility during islet cell differentiation. Furthermore, we discuss the consequences of FOXA2 dysregulation, including impaired α- and β-cell maturation, loss of functional identity, and contributions to the pathogenesis of diabetes. Insights from mouse models, human stem cell-derived islets, and patient genetics underscore the clinical relevance of FOXA2 in monogenic and complex forms of diabetes. By integrating developmental biology, genomics, and disease modeling approaches, this review highlights FOXA2 as a central regulator connecting pancreatic organogenesis with long-term metabolic control. Understanding FOXA2's regulatory networks may open new avenues for therapeutic strategies aimed at restoring or preserving β-cell function in diabetes.

Antibacterial prophylaxis has long been a cornerstone of supportive care in patients with haematological malignancies undergoing intensive chemotherapy and haematopoietic stem cell transplantation (HSCT), particularly in the setting of prolonged and profound neutropenia. However, the widespread use of fluoroquinolone (FQ) prophylaxis has increasingly raised concerns related to antimicrobial resistance, microbiota disruption, drug-related toxicity, and Clostridioides difficile infection, challenging its universal application. At the same time, the therapeutic landscape of haematology is rapidly evolving, with the introduction of novel agents and cellular therapies such as chimeric antigen receptor (CAR) T cells, bispecific antibodies (BsAbs), antibody-drug conjugates, and immune-based treatments, each associated with distinct patterns of immunosuppression and infectious risk. In this narrative review, we critically examine the role of antibacterial prophylaxis through the lens of antimicrobial stewardship, integrating evidence from traditional chemotherapy and transplantation with emerging data from innovative therapies. We summarize current guideline recommendations, real-world evidence, and recent studies questioning the net benefit of routine FQ prophylaxis, particularly in settings with high resistance prevalence. Alternative strategies, including non-FQ agents and selective omission of prophylaxis, are also discussed. Overall, available evidence supports a shift from universal prophylaxis toward a risk-adapted, individualized approach that accounts for treatment modality, expected duration and depth of neutropenia, patient-specific factors, and local epidemiology. Embedding antibacterial prophylaxis decisions within structured antimicrobial stewardship programs is essential to balance infection prevention with long-term patient safety and resistance containment in modern haematological practice.

Severe acute pancreatitis (SAP) is a complex inflammatory disorder with severe immune imbalance. This study investigates the therapeutic potential of extracellular vesicles derived from human adipose mesenchymal stem cells (hADSC-EVs) in modulating Treg differentiation and alleviating SAP. We conducted a phosphoproteomics analysis to evaluate phosphorylation levels, and administered hADSC-EVs in a mouse model of SAP and assessed their impact on Treg differentiation. Phosphoproteomics revealed a significant increase in p-STK3 following hADSC-EVs treatment, restoring Foxp3 level diminished by STK3 knockdown. HADSC-EVs promoted Treg differentiation in a concentration-dependent manner by targeting Foxp3 transcription. In the SAP mouse model, hADSC-EVs improved survival rates and mitigated histopathological alterations. In conclusion, our study revealed that STK3 effectively promotes Treg differentiation and enhances their immunosuppressive capabilities, thereby ameliorating inflammation and attenuating the pathological phenotypes associated with SAP. These findings provide valuable insights into the potential role of hADSC-EVs in regulating immune responses and promoting tissue repair.

Sponges are capable of rebuilding functional individuals from cell aggregates (primmorphs), a process termed whole-body regeneration that morphologically parallels larval development. To systematically compare these processes, we established an in vitro primmorph regeneration model in Haliclona simulans and performed multi-level analyses across planktonic, settled, and metamorphic stages. Although both processes formed similar structures (e.g., the aquiferous system), planktonic primmorphs exhibited a reduced stem cell proportion (archeocyte/choanocyte), along with the increase of seemingly dedifferentiating cells and vacuolar cells. Microbiome diverged: while sharing core symbionts (e.g., AqS1), primmorphs enriched Tenacibaculum and Vibrio species during remodeling process. Transcriptomics revealed distinct signatures: regeneration upregulated genes potentially related to DNA repair and dedifferentiation but downregulated stem cell markers. Our integrative study indicates that regeneration and development constitute distinct processes, achieving similar functional outcomes via divergent cellular, microbial, and molecular profiles that provides a foundational framework for future mechanistic studies of regeneration.

Akhunbay-Fudge et al. develop two complementary single-cell profiling methods to determine glioblastoma (GB) invasion phenotypes, focusing on the influence of host organoid developmental lineage (neural versus endodermal) and cell cycle progression on GB invasion within tumor assembloids. Notably, GB cells invaded both neural and endodermal organoid hosts, whereas non-malignant adult brain cells lacked this capacity. Single-cell mRNA sequencing revealed gene expression changes in invading tumor cells and surrounding environmental assembloid cells. Concurrently, the "DyPheT" automated tracking tool enabled real-time correlation of cell cycle phases with malignant cell migration within cerebral organoids, which can be utilized for treatment response assessment, exemplified by the investigational compound RP-6306. Collectively, these approaches identify an intrinsic (cell autonomous) gene expression signature linked to GB invasion and support a "go-and-grow" paradigm by revealing a highly migratory (and RP-6306-refractory) GB subpopulation active in the G2/M phase of cell cycle.

Following their engagement towards differentiation, tissue stem cells often transit through a precursor state that is difficult to define because of its transient nature; similarly, the precise role of lineage precursors in implementation of tissue architecture and function is unknown. In the present work, we used two mouse models of deficient feedback regulation to characterize precursors of the pituitary corticotrope lineage that regulates the stress response. Both the POMC knockout and adrenalectomized mouse models develop glucocorticoid deficiency and compensatory accumulation of corticotrope precursors that have so far eluded characterization. We found that pre-corticotrope differentiation depends on the lineage-specific factor Tpit and is repressed by glucocorticoids. We identified brain-derived neurotrophic factor (BDNF) as the signal that engages pituitary stem cells towards differentiation in these models as well as in normal pituitary development. A glucocorticoid-sensitive BDNF autocrine loop active in pre-corticotropes turns these cells into signaling hubs for maintenance of pituitary-adrenal homeostasis.

Colonic stem cells reside in a microenvironment enriched in epidermal growth factor, which is essential for their survival and can activate both PI3K-AKT and MAPK-ERK pathways. This predicts co-activation of both pathways within the growth factor-high stem cell compartment at the base of crypts. However, in patient-derived human colonic organoids and normal human tissue, stem cells maintain robust AKT activity while suppressing ERK signaling despite active EGFR engagement. As stem cells differentiate, they activate pulsatile ERK signaling, which is essential for migration, survival, and maintenance of barrier function. We show that AKT-dependent phosphorylation of RAF-1 at serine 259 establishes a post-receptor checkpoint that maintains ERK temporal dynamics in stem cells. Acute activation of ERK in stem cells triggers rapid global differentiation. Disruption of the ERK checkpoint via mutation of serine 259 leads to sustained AKT and ERK co-activation in stem cells. Unlike ERK/AKT coactivation driven by apoptosis, co-activation in the stem cell compartment results in the emergence of a neoplastic, architecturally disorganized cell population dominating the cell fate profile. Incredibly, introducing brief ERK pulses through AKT inhibition or ERK activation triggers re-differentiation of neoplastic cells. Consistent with duration-dependent MAPK encoding principles, these data demonstrate that regardless of baseline signaling amplitude, ERK signaling dynamics are epistatic to total kinase signaling load in human colonic stem cells.

Adult zebrafish exhibit scarless repair and functional recovery following spinal cord injury. Their regenerative capacity is attributed to potent stem-like progenitors that mediate neuronal and glial repair. Zebrafish are thought to lack anti-regenerative extracellular matrix (ECM) components abundant in mammalian SCI, but the positive contributions of ECM to spontaneous spinal cord repair are less understood. By employing cross-species single-cell transcriptomics, we found the hyaluran modifying enzyme Hapln1 is upregulated in zebrafish progenitors but not in mouse progenitors following injury. Loss-of-function of hapln1a/b and ablation of hapln1+ cells reduce progenitor cell activation and hinder spontaneous recovery from injury. Using a series of in vivo and in vitro assays, we show that Hapln1 is required for hyaluran- cd44b mediated progenitor cell proliferation. This study reveals that, in addition to lacking anti-regenerative ECM components around SC lesions, zebrafish can also leverage pro-regenerative ECM molecules to enhance progenitor cell potency and promote repair.

JAK2 is a key regulator of cytokine-mediated proliferative signaling in hematopoietic stem and progenitor cells. Activating mutations, most commonly JAK2 V617F, trigger aberrant cytokine signaling driving the pathogenesis of myeloproliferative neoplasms (MPNs). Phosphatidylinositol transfer proteins (PITPs) facilitate phosphoinositide synthesis by delivering phosphatidylinositol to lipid kinases, though their roles in oncogenic signaling have remained poorly defined. Here we show that PITPβ is critical for the development of JAK2V617F-driven MPN in mice. Deleting Pitp β across the hematopoietic system, but not Pitp α, prolonged 25-week survival of Jak2V617F mice from 10% to 85%. Loss of Pitp β attenuated disease-associated splenomegaly and curtailed erythroid progenitors expansion both in vivo and in vitro . Mechanistically, PITPβ is necessary for AKT hyperactivation in hematopoietic progenitors, while STAT5 and ERK signaling remain unaffected. In alignment with this role, PITPβ promotes the production of PtdIns(3,4)P ₂ , a phosphoinositide that sustains aberrant AKT signaling in Jak2V617F progenitors. Pharmacologic inhibition of AKT with the FDA-approved inhibitor capivasertib in Jak2V617F-transplanted mice similarly reduced splenomegaly and erythroid proliferation, mimicking the effects of Pitp β loss. Collectively, these results identify a novel PITPβ-PtdIns(3,4)P ₂ signaling axis that selectively maintains pathological AKT activation in JAK2V617F-driven MPN, revealing a promising therapeutic vulnerability.

The diarrheal disease cholera remains a global threat, but there is limited knowledge of the innate immune defenses in the small intestine that protect against the causative agent, Vibrio cholerae. Here, single-cell RNA-sequencing of epithelial and immune cells mapped gene expression patterns in the infant mouse small intestine and revealed changes in response to V. cholerae infection and prophylactic treatment with an IL22 Fc-fusion protein. Infection increased the abundance of an enterocyte subtype with high expression of defense-associated functions and stimulated production of IL22, a cytokine linked to epithelial integrity, from group 3 innate lymphoid cells. Administration of IL22Fc increased production of vibriocidal Reg3β from enterocytes and the abundance of secretory lineage and Muc2-producing goblet cells, which secreted mucus into the intestinal crypts, impairing V. cholerae association with the epithelium. These IL22-mediated responses limited V. cholerae intestinal colonization and protected mice from diarrhea and death. Our findings suggest enterocyte specialization in mucosal defense.

The mammalian kidney relies on a branched network of collecting ducts for fluid transport and homeostasis. Replicating this network in vitro would parallelize function in synthetic replacement kidneys, yet current organoids have limited branching capacity. Here, we establish a developmentally-informed strategy to control organoid budding through optogenetic control of a receptor tyrosine kinase, RET. We first show pharmacological manipulation of RET signaling controls the extent of branching in mouse embryonic kidneys and human stem cell-derived kidney organoids. Next, we develop an optogenetic RET receptor (optoRET) that signals in a ligand-independent manner via blue light-mediated clustering. Epithelial cells expressing optoRET reproduce stereotyped RET signaling, scattering, and symmetry breaking in response to blue light. Human kidney organoids undergo budding with controllable orientation in response to spatially patterned optoRET stimulation. Our results establish ligand-free optogenetic control of branching and inspire new synthetic biology strategies for epithelial organoid design.

Carbohydrates are classically catabolized by fermentation or oxidation, a choice that impacts many cellular functions including proliferation. Proliferating cells including somatic stem and progenitor cells are thought to favor fermentation over oxidation, and most proliferating cells in vitro depend on lactate production. However, it has not been tested if fermentation and oxidation are the universal obligatory terminal fates for carbohydrates in vivo because the key enzymes, lactate dehydrogenase (LDH) and pyruvate dehydrogenase (PDH), have not been simultaneously deleted in any cell type. Here we show that both fermentation and oxidation are dispensable for the survival and function of hematopoietic stem cells (HSC). Combined LDHA and LDHB deletion to ablate LDH did not impair HSC function, suggesting that HSCs and rapidly proliferating hematopoietic progenitors surprisingly do not require fermentation. Combined LDHA, LDHB, and PDH deletion abolished both glucose oxidation and fermentation, but did not impair HSC function. Glycolysis was preserved, suggesting the operation of an alternative endpoint. LDH/PDH-deficient HSCs terminated glycolysis through pyruvate export. Pyruvate export by HSCs and progenitors was a physiological response to changing nutrient levels. Quadruple deletion of LDHA/B, PDH, and the pyruvate transporter MCT1 impaired HSC function. This suggested that an essential role of glycolysis termination is not to produce acetyl-CoA or lactate but to remove pyruvate. Therefore, in contrast to classical theories and to in vitro metabolism, carbohydrate metabolism in vivo does not require oxidation or fermentation but can terminate directly in pyruvate export, and this alternative pathway is sufficient to support stem cell function.

DNA repair in biochemical and genetic experimental systems permits a precise definition of enzyme requirements and mechanistic steps. Comparing these findings to repair events at naturally occurring damage sites in multicellular organisms is essential for confirming and expanding these insights into a physiologic context. However, heterogeneity in any normal cell population increases with each cell division, and the reliable detection of replication-independent DNA damage sites and their repair has been a major barrier. Here, we examine single human colon crypts, which harbor natural cell clones, using a novel whole-genome sequencing (WGS) method to identify complex insertion-deletion (indel) in the crypt stem cells. Analysis of complex indel events likely repaired by non-homologous end joining occurring in crypt stem cells permits inferences about the in vivo repair of naturally occurring DNA damage within physiologically-relevant chromatin in normal human cells.

Parkin, an E3 ubiquitin ligase encoded by PARK2, plays a key role in both hereditary and sporadic Parkinson's disease (PD), yet there are no therapies currently available that can target this important pathway. Here, we show that Parkin is critical for successful neuronal differentiation and survival, and we develop small-molecule Parkin agonists that can protect dopaminergic neurons. Upon differentiation of neural progenitor cells, loss of Parkin results in a reduced capacity to maintain neuronal cell state, dopaminergic neuronal phenotypes, and stress resistance. Moreover, Parkin loss disrupted cell morphology and the stability of neurites. Transcriptional and single-cell analyses reveal that Parkin controls critical pathways regulating stem-like cell transitions and is needed for stable neuronal maturation. We also examined the effects of FB231, a small molecule enhancer of Parkin E3 ligase activity, in models of PD. FB231 reduced pathological α-synuclein and enhanced cell survival in human iPSC-derived dopaminergic neurons treated with α-synuclein preformed fibrils. Furthermore, FB231 attenuated a α-synuclein pathology and dopaminergic neurodegeneration in a gut α-synuclein murine model of PD. Our findings support that Parkin plays a crucial role in maintaining neuronal homeostasis and that pharmacologic activation of Parkin may be a promising strategy to attenuate neurodegeneration in PD.

Filamentation induced by cAMP domain-containing protein (FICD) is an endoplasmic reticulum (ER)-resident adenylyltransferase that catalyzes protein AMPylation, a post-translational modification. Although FICD-mediated AMPylation has been linked to the fine-tuning of proteostasis and neuronal integrity, its role in neurodegenerative diseases characterized by protein dyshomeostasis remains unclear. Parkinson's disease (PD) is defined by dopaminergic neurodegeneration and aggregation of α-synuclein (aSyn) as a consequence of impaired protein homeostasis. We therefore investigated whether dysregulated FICD-mediated AMPylation contributes to PD pathogenesis.

Centromeres ensure proper chromosome segregation during cell division, yet the organization and regulation of centromeric chromatin within satellite DNA arrays remain incompletely understood. Here, we leverage the complete diploid human genome benchmark (T2T-HG002) to provide a detailed study of centromeric sequence and chromatin architecture on individual haplotypes. Using adaptive-sampling-enriched, ultra-long-read DiMeLo-seq, we achieve single-molecule chromatin profiling across all centromeres, revealing that along single chromatin fibers, CENP-A, the histone variant specifying centromere identity, forms multiple discrete subdomains within hypomethylated centromere dip regions (CDRs) that are flanked by H3K9me3-enriched heterochromatin. Despite underlying sequence variation, CDRs localize to sequence-homogeneous domains and maintain relatively balanced CENP-A dosage and aggregate length across all chromosomes and between haplotypes. Further, we show that bidirectional changes to centromeric and pericentromeric DNA methylation are accompanied by changes to centromeric chromatin architecture. In passaged cells with centromeric hypomethylation, subdomain boundaries are eroded, and adjacent CENP-A domains tend to merge and expand. Conversely, in pluripotent stem cells with centromeric hypermethylation, CDRs are fundamentally reorganized, such that discrete hypomethylated domains are frequently consolidated into broader contiguous tracts. These methylation-associated CDR restructuring events suggest that DNA methylation acts as a principal regulator of human centromere organization, with implications for understanding centromere plasticity, epigenetic inheritance, and chromosomal instability in development and disease.

Chimeric antigen receptor (CAR) T cell therapy has transformed the treatment of B cell malignancies, but translation to acute myeloid leukemia (AML) has been hindered by on-target, off-tumor (OTOT) toxicity. In particular, endothelial cell (EC)-specific toxicity has limited clinical translation of promising leukemia stem cell-enriched targets such as CD93. Innovative strategies to mitigate EC damage while preserving antileukemic efficacy are needed.

Astrocytes play a key role in neuronal homeostasis and in various neural disorders. The generation of astrocytes from neural progenitor cells (NPCs) and its functions are under a complex control of several signaling networks and transcription factors. In this study, we demonstrate that the transcription factor, GLIS similar 3 (GLIS3), which has been implicated in several neurodegenerative diseases, is highly expressed in astrocytes, and is required for the efficient differentiation of human NPCs into astrocytes. Loss of GLIS3 function greatly impairs astrocytes differentiation, resulting in reduced expression of astrocyte markers, whereas expression of exogenous GLIS3 restores the induction of astrocyte specific genes indicating a critical role for GLIS3 in astrocyte differentiation. Integrated transcriptomic and cistromic analyses revealed that GLIS3 directly regulates the transcription of several astrocyte-associated genes, including GFAP , SLC1A2 , NFIA , and ATF3 , in coordination with lineage-determining factors, such as STAT3, NFIA, and SOX9. We hypothesize that GLIS3 dysfunction disrupts this transcriptional network thereby contributing to astrocyte-associated neurological disorders. Identification of GLIS3 as a key regulator of astrocyte differentiation and gene expression will advance our understanding of its role in neurodegenerative diseases and may provide a new therapeutic target.

A recent clinical study tested the effects of two different monoclonal antibodies (mAbs) (siltuximab, anti-IL6; tocilizumab, anti-IL6R) on the fate and function of T-cells in people with type 1 diabetes. While both mAbs affect the response of T-cells to stimulation, they have very different, sometimes opposing mechanisms. Here, we use mass-spectrometry based proteomics to analyze longitudinal serum samples (baseline and two weeks post-treatment) from 20 clinical trial participants to examine the effects of siltuximab and tocilizumab on extracellular vesicles. To accomplish this, serum samples were enriched for extracellular vesicles with Mag-Net and analyzed by LC-MS/MS to identify significantly differentially abundant protein groups and pathways. Proteome analysis confirmed highly reproducible measurements across multiple draw dates. In total, we quantified >3300 protein groups of which 46 protein groups had significantly altered abundance after mAb treatment. Tocilizumab altered pathways associated with proteostasis (neddylation) and pre-notch transcription and translation. Siltuximab altered FCGR activation pathway members. In addition, quantitation of the monoclonal antibody therapies themselves enabled the measurement of the correlation between drug amounts and impacted proteins. Taken together, this work demonstrates the utility of the Mag-Net method to evaluate the impacts of therapeutic interventions on serum extracellular vesicles.