Relapse is a major cause of treatment failure after allogeneic hematopoietic stem-cell transplantation(allo-HSCT) for high-risk myeloid malignancies. This single center, retrospective study enrolled patients with high-risk acute myeloid leukemia or myelodysplastic syndromes who received allo-HSCT from January 1, 2022 to December 31, 2024. Post-transplant maintenance therapy consisted of azacitidine (32 mg/m²/day, day 1-5) plus venetoclax (400 mg/day, day 1-7), starting from the 60th day posttransplant and repeated every 28 days until up to 1-year posttransplant. Outcomes were compared with a contemporaneous control group constructed via propensity score matching (azacitidine-venetoclax, n = 35; control, n = 59). After a median follow-up of 22.5 months, the 1-year disease-free survival was 88.6% (95% CI, 78.6%-99.8%), the 1-year cumulative incidence of relapse was 5.7% (95% CI, 0%-13.5%). The azacitidine-venetoclax group demonstrated significantly superior 1-year overall survival compared to control (P = 0.037). Win ratio analysis further confirmed a significant overall clinical benefit (P < 0.001). Subgroup analysis revealed a pronounced overall survival benefit for MRD-positive patients (HR, 0.288; P = 0.037). The safety profile was manageable, no significant increase in the incidences of EBV and CMV infection or graft-versus-host disease. Immune reconstitution analysis showed delayed B-cell recovery but preserved T-cell and NK-cell recovery.

BACKGROUND:Immune reconstitution is critical for outcomes after allogeneic hematopoietic stem cell transplantation (allo-HSCT), but its prognostic role in haploidentical peripheral blood stem cell transplantation (haplo-PBSCT) remains unclear. METHODS:We retrospectively analysed 577 patients who underwent T-cell replete haplo-PBSCT between 2016 and 2024. Longitudinal reconstitution of CD4⁺, CD8⁺ T cells and their subsets, CD3⁺CD69⁺, CD3⁺HLA-DR⁺ T cells, NK cells and B cells was assessed from 1 to 12 months post-transplant. Cox regression and causal mediation analyses were performed to identify prognostic associations and mechanisms. RESULTS:Early and robust regulatory T cell (Treg) reconstitution significantly reduced transplant-related mortality (TRM) and improved overall survival. Naïve CD8⁺ T cell recovery correlated with reduced TRM and relapse. Higher late CD3⁺CD69⁺ T cells were linked to decreased relapse risk. Sustained B cell reconstitution reduced TRM and was associated with a lower incidence of moderate-to-severe chronic graft-versus-host disease. Early Treg reconstitution was associated with lower cytomegalovirus (CMV) reactivation. Mediation analysis revealed that Treg recovery reduced TRM partially through suppression of CMV reactivation (ACME = -0.22, p = 0.032). CONCLUSION:Distinct lymphocyte subset reconstitution profiles predict transplant outcomes in haplo-PBSCT. Early Treg recovery, partly by limiting CMV reactivation, may serve as a target for immune-guided intervention.

Reduced-intensity conditioning (RIC) is associated with a high relapse rate in high-risk acute myeloid leukaemia (AML) and myelodysplastic syndromes (MDS) undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT). It remains unclear whether venetoclax, an anti-leukaemic agent, can enhance RIC efficacy. A prospective, single-arm, phase 2 trial enrolled patients with high-risk AML or MDS, aged ≥55 years, who underwent allogeneic peripheral blood stem cell transplantation (allo-PBSCT). All patients received venetoclax-enhanced RIC (VEN-RIC), comprising venetoclax, busulfan, fludarabine, cytarabine and low-dose total body irradiation (TBI). Fifty patients (median age 62) were enrolled. At a median follow-up of 14.9 months, the 1-year progression-free survival (PFS) was 72.5%, while 1-year overall survival (OS) and graft-versus-host disease/relapse-free survival (GVHD/GRFS) were 73.8% and 56.9% respectively. The 1-year cumulative incidence of relapse and non-relapse mortality were 16.8% and 10.6%. The 180-day cumulative incidence of acute GVHD was 22.9%, while the 1-year cumulative incidence of chronic GVHD was 25.8%. Multivariable analysis showed TP53 mutation was the strongest predictor of worse OS, PFS and GRFS, as well as higher relapse. We conclude that VEN-RIC is feasible and associated with encouraging survival and a manageable safety profile, warranting confirmation in randomized studies.

Post-transplant relapse remains the chief therapeutic challenge in Ph-negative B cell acute lymphoblastic leukemia (Ph - B-ALL). This retrospective study evaluated whether short-course blinatumomab for measurable resident disease (MRD) eradication could improve transplant outcomes. We compared 23 patients receiving pre-transplant short-course blinatumomab (2-week) for MRD eradication with 46 chemotherapy-only controls. All achieved MRD-negative before allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Only two patients developed grade 2 cytokine release syndrome with blinatumomab. The neutrophil and platelet engraftment times were similar between the two groups. The blinatumomab cohort had a significantly lower 18-month cumulative incidence (CI) of relapse ( p = 0.05) and chronic graft-versus-host disease (GVHD) (14.8% vs. 41.8%; p = 0.05), with comparable non-relapse mortality (NRM) ( p = 0.98) and 180-day grade II-IV acute GVHD rates ( p = 0.93). Consequently, this cohort showed superior 18-month relapse-free survival (RFS) (90.9% vs. 65.2%; HR 0.30, 95% CI 0.09-1.04; p = 0.04), improved 18-month overall survival (OS) (95.7% vs. 81.9%; HR 0.20, 95% CI 0.03-1.71), and a trend toward better GVHD-free and relapse-free survival (GRFS) (74.71% vs. 63.71%; HR 0.64, 95% CI 0.23-1.78). Multivariate analysis confirmed blinatumomab as an independent favorable factor for RFS. In conclusion, short-course blinatumomab as a bridge-to-transplantation could reduce the risk of relapse and improve survival for Ph - B-ALL patients undergoing allo-PBSCT.

Abstract Background Blood testing aids pneumonia diagnosis, but its effectiveness varies. Given the invasiveness of bronchoalveolar lavage fluid (BALF) sampling versus blood testing’s simplicity, this study investigates when blood can reliably substitute for BALF in detecting microbial presence, especially for pathogens. Results Metagenomic sequencing was performed on paired BALF-blood samples from 21 post-HSCT immunocompromised (ICP) and 21 immunocompetent (ICT) patients. The ICP cohort was expanded to 62 for biomarker validation. Host responses were profiled via metatranscriptomics (30 BALF samples). Microbial alpha and beta diversity differed significantly between blood and BALF in ICP, but not ICT, patients. ICP patients’ BALF contained a greater diversity and abundance of microbes. A higher proportion of microbial DNA sequences in ICP patients’ blood was also present in their BALF, suggesting a potentially more permeable alveolar-capillary barrier. Related genes (e.g., NABA CORE MATRISOME, extracellular matrix organization, cell-cell adhesion) were downregulated. Upregulated pathways like VEGFA-VEGFR2 signaling and Rho GTPases suggested increased vascular permeability. In ICP patients, 419 microbial sequences in blood indicated their presence in the lower respiratory tract with > 70% certainty. Conclusion Host immune status significantly influences blood-BALF microbial diversity differences. Shared blood-BALF microbial DNA sequences show potential for aiding pneumonia pathogen diagnosis, offering a novel biomarker identification approach.

S5. LA dramatically enhances malignancy of cancer cells with low expression of YY1.

Tumor-associated macrophage (TAM) is an important component of immunosuppressive microenvironment, which has been indicated as a key contributor in the relapse of diffuse large B-cell lymphoma (DLBCL). However, the molecular mechanism and the potential intervention regulating DLBCL-TAMs remains undefined. Here, we found that histone deacetylases (HDACs)-induced STAT3 deacetylation was critical for the M2 macrophages accumulation in DLBCL. Considering the unignorable adverse effects of HDAC inhibitor chidamide in DLBCL treatment, we developed a M2-targeted delivery system with peptide-modified extracellular vesicle (M2pep-EVs) to obtain optimized intra-tumour delivery of chidamide. In combined with pH-responsive hydrogel TSPBA/PVA, chidamide was loaded in M2pep-EVs, and was intelligently released as Chid@M2pep-EVs in situ in the acidic lymphoma microenvironment. By targeted delivery to M2 macrophages, chidamide sufficiently inhibited HDACs, enhanced STAT3 acetylation, reprogrammed M2 proportion into M1 phenotype, and ultimately suppressed lymphoma growth in vivo. With reduced dosage and adverse reactions, our Chid@M2pep-EVs system provides a new translational strategy for treating refractory/relapsed lymphoma.

S6. Brief schematic of lactate-induced YY1 degradation via chaperone-mediated autophagy for tumor growth and malignancy.

Supplementary Table S1. Oligonucleotides.

Supplementary Table S2. Hit-region sequences

Cancer metabolic reprogramming generates a hostile tumor microenvironment (TME) characterized by lactate-driven acidosis, fostering tumor progression. Epstein-Barr virus (EBV), an oncogenic herpesvirus linked to multiple malignancies, thrives under such stress, yet how it interacts with and contributes to an acidic TME remains poorly understood. Here, we identify miR-7-5p as a lactate-downregulated microRNA with diagnostic potential in plasma from patients with EBV-associated diffuse large B cell lymphoma and nasopharyngeal carcinoma. TRIM33, a previously uncharacterized lactate-inducible transcriptional regulator of glycolytic flux, is directly targeted by miR-7-5p. Integrative multi-omics analyses reveal that lactate promotes TRIM33 binding to specific motifs in the promoters of key glycolytic genes, including SLC16A1, which enhances their expression and reprograms metabolism. Importantly, the loss of TRIM33 accelerates tumor growth, enhances EBV reactivation, and confers resistance to lactate-transporter inhibitors. Our finding provides circulating miR-7-5p as a noninvasive biomarker and reveals TRIM33 as an integrator of lactate stress, metabolism, and viral oncogenesis, offering a novel dual-targeting therapeutic strategy.

Full engraftment and early immune reconstitution of donor hematopoietic stem cells (HSCs) after allogeneic HSC transplantation (allo-HSCT) are crucial. However, effective and safe clinical modality remains lacking. Here, very-late antigen (VLA-4) was identified as a pivotal target for HSC engraftment, and one of its agonists was identified, which significantly promotes donor HSC engraftment and long-term hematopoietic reconstitution by enhancing its self-renewal capacity in allogeneic transplantation and serial xenotransplantation mouse models. Furthermore, the VLA-4 agonist facilitated early immune reconstitution by augmenting T-cell differentiation from HSCs, with the reconstituted immune cells exhibiting potent antiviral effects without exacerbating acute graft-versus-host disease. Mechanistically, VLA-4 A2 activated ERK1/2 phosphorylation to regulate HSC function and lymphoid progenitor differentiation, without inducing leukemogenic gene expression. These findings underscore the significant clinical translational potential of the VLA-4 agonist in promoting HSC engraftment and early cellular immune reconstitution following allo-HSCT.

Pseudomonas aeruginosa infection poses a significant clinical challenge in respiratory diseases by subverting host defense mechanisms. While inflammatory responses in airway epithelial cells (AECs) during infection have been extensively studied, the interplay between epitranscriptomic regulation and metabolic reprogramming remains poorly understood. Here, we identify a lactylation-N6-methyladenosine (m6A) axis that orchestrates ciliary function and antibacterial defense through dual-layer metabolic-epigenetic coordination. Using integrated in vivo and in vitro models, we demonstrate that P aeruginosa infection depletes host lactic acid through direct consumption via lactate dehydrogenase and virulence factor-mediated glycolytic suppression. This metabolic perturbation reduces histone H3K18 lactylation, diminishing m6A methylation by directly downregulating YTHDF1; m6A sequencing analysis reveals preferential hypomethylation of dynein axonemal heavy chain 5 (DNAH5) mRNA, a critical regulator of ciliary motility. Mechanistically, YTHDF1 recognizes m6A-modified DNAH5 transcripts to stabilize translation. The lactylation-YTHDF1-DNAH5 axis proves essential for maintaining ciliary beat frequency and mucociliary clearance capacity. This metabolic-epitranscriptomic circuitry significantly impacts host defense, as evidenced by increased bacterial burden in conditional YTHDF1 knockout mice. Our findings extend the paradigm of lactylation-mediated gene regulation to airway pathophysiology, revealing a novel mechanism where microbial-induced metabolic perturbations reprogram RNA modification landscapes to disable ciliary defenses. This study establishes a conceptual framework for understanding how opportunistic pathogens exploit host metabolic-epigenetic networks to establish persistent infections, suggesting therapeutic potential for targeting the lactate-YTHDF1 axis in P aeruginosa-associated pulmonary disorders.

S1. Lactate induces cytoplasmic accumulation and nuclear loss of YY1, but not YY2.

Abstract The optimal graft-versus-host disease (GVHD) prophylaxis strategy in haploidentical peripheral blood stem cell transplantation remains controversial. In this open-label, phase 3 study, patients aged 14 to 70 years with acute myeloid leukemia or myelodysplastic syndromes with excess blasts Ⅰ or Ⅱ were randomized (2:1:1) to receive low-dose antithymocyte globulin (ATG; 5 mg/kg) plus posttransplant cyclophosphamide (PTCy; 50 mg/kg; referred to as ATG/PTCy), standard-dose ATG (total dose, 10 mg/kg), or a PTCy-based (total dose, 100 mg/kg) regimen for GVHD prophylaxis. The coprimary end points were the cumulative incidence (CI) of grade 2 to 4 acute GVHD (aGVHD) by day 100 and GVHD-free, relapse-free survival at 1 year after transplant. A total of 407 patients were randomized to receive an ATG/PTCy (185 patients), ATG (113 patients), or PTCy (109 patients) regimen for GVHD prophylaxis. By day +100, the CI of grade 2 to 4 aGVHD did not differ significantly among the 3 groups (P = .210). Although the overall incidence of chronic GVHD (cGVHD) was comparable across all groups (P = .110), the 2-year CI of moderate-to-severe cGVHD was numerically lower in the ATG/PTCy (17.4%) and ATG (17.3%) groups than the PTCy group (28.3%), without reaching statistical significance (P = .095). No significant differences were observed in survival outcomes among the 3 groups. Notably, the CI of neutrophil and platelet recovery was significantly higher in the ATG/PTCy group than in the other groups (P< .001). This trial suggested that the 3 GVHD prophylaxis strategies presented similar efficacy in preventing grade 2 to 4 aGVHD and yielded comparable survival. This trial was registered at www.clinicaltrials.gov as NCT03608059.

S2. Distribution of WT YY1 and its mutants in the presence or absence of LA.

Pituitary neuroendocrine tumors (PitNETs) are pathologically characterized by dysregulation of neuroendocrine function and systemic disruption of hormonal homeostasis, yet their regulatory effects on peripheral immune networks remain poorly characterized. Here, we systematically analyzed bulk RNA sequencing (RNA‑seq) from 883 PitNET tumors, 108 PitNET‑associated peripheral blood mononuclear cells (PBMC) samples, and 175 healthy PBMC controls, combined with 69 single‑cell RNA sequencing (scRNA-seq) samples covering tumors, normal pituitaries, as well as tumor‑derived and normal PBMCs. We identified a systemic immune disequilibrium in PitNET patients, characterized by increased circulating lymphocyte proportions, accompanied by upregulated cytokine-receptor interaction signatures. Notably, tumor resection reversed this imbalance, as supported by the normalization of monocyte and neutrophil counts, validated by flow cytometry and routine blood data from 600 samples (200 healthy controls and 200 PitNET patients with paired pre- and post-surgery follow‑up). Trajectory analysis identified terminally differentiated, secretory-specialized cell populations with lineage-specific hormone and cytokine hypersecretion. Ligand-receptor inference suggested these tumor-derived factors potentially engage circulating immune cell receptors. A random‑forest classifier based on PBMC transcriptomes distinguished PitNET subtypes, underscoring the diagnostic potential of peripheral immune signatures. Furthermore, in an estrogen-induced rat model, elevated PRL level coincided with the same peripheral immune skewing. Overall, our work provides a valuable resource and demonstrates PitNETs can be systemic immune modulators, where intrinsic hormone secretory activity and monocyte-lymphocyte imbalance collectively drive peripheral immune dysfunction.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the cornerstone of curative therapy for acute myeloid leukemia (AML), yet precise molecular prognostic tools are currently insufficient. This study developed a prognostic model, AML-PRSS, integrating genomic and clinical factors from 389 adult AML patients undergoing their first allo-HSCT between 2013 and 2021. Seven genetic mutations significantly associated with leukemia-free survival (LFS) were categorized as favorable (DNMT3A, CEBPA bZIP domain, NPM1 without FLT3-ITD or with FLT3-ITD plus tyrosine kinase inhibitors), unfavorable (NRAS and GATA2), and high-risk (TP53 and U2AF1). Multivariate analysis identified molecular risk, cytogenetic risk, pre-transplant disease status, age, and hematopoietic cell transplant-comorbidity index (HCT-CI) score as independent predictors of LFS. AML-PRSS stratified patients into four risk groups with stepwise increasing hazard of LFS failure. Validation in an independent multi-center cohort of 266 patients confirmed robust predictive accuracy, highlighting AML-PRSS as an effective tool for personalized prognostication and clinical decision-making.