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Fang, D.

Publications and source records attributed to Fang, D..

At least 19 recordsLinked to original sources

CAR T cell foundation model predicts immunotherapy response

Single-cell transcriptomics resolves CAR T-cell states, yet translating heterogeneous cellular signals into patient-level therapeutic response remains challenging. Existing studies primarily identify response-associated genes or cell populations through experimental and statistical analyses, but few predictive frameworks integrate gene-level structure with clinical outcomes. Here, we present gANCHOR, a T-cell foundation model built on a hierarchical hypergraph attention framework combining biologically informed representation learning with patient-level response prediction. By encoding gene-pathway relationships, gANCHOR learns pathway-aware cell embeddings that improve biological conservation and batch robustness. A cell-to-patient attention module then aggregates cellular information to infer therapeutic response. Across benchmark datasets, gANCHOR achieved the strongest overall performance in biological conservation and batch-correction assessments. In response prediction across 161 patients from five CAR T-cell studies, gANCHOR achieved an F1 score of 0.87, outperforming benchmarked single-cell foundation models. gANCHOR also identified reproducible response- and non-response-associated gene programs, providing interpretable biological insights into CAR T-cell efficacy and resistance.

bioinformatics↗

AI-enabled Spatial Profiling of Circulating Tumor-Immune Ecosystems Predicts Patient Outcomes Across Cancers

Circulating tumor cells (CTCs) and immune cells form dynamic multicellular ecosystems in blood, but their spatial organization and clinical relevance have not been systematically characterized. We developed the Cell and Cluster Identification Program (CCIP), an artificial intelligence-based framework that analyzes routine multiplex immunofluorescence blood scans to segment cells, identify CTCs and five immune lineages with high accuracy, and quantify multicellular clusters and tumor-immune interactions. Applying CCIP to 2,693 blood scans from 1,399 patients, we profiled over 60 million cells (>7 million multi-cell clusters) and linked imaging-derived features to patient outcomes. Correlated with circulating-tumor DNA mutation burdens, a 14-feature image model predicted overall survival in breast cancer, outperformed clinicopathologic variables and CTC enumeration, and generalized to prostate cancer. Prognostic imaging signatures were also associated with therapy response-related progression-free survival as well as with single-cell RNA sequencing-derived immune suppression states, connecting circulating tumor-immune architecture with systemic immune dysfunction.

cancer biology↗

Histone modifications analysis reveals enhancers reprogramming during maternal-to-zygotic transition

Enhancers are important epigenetic regulatory components that coordinate spatiotemporal gene expression and play a crucial role in mammalian development, gene regulation, and illness. During early mammalian embryogenesis, histone modifications including H3K4me1, a canonical enhancer mark, and H3K27ac, which identifies active enhancers, are still poorly understood. This study profiles the genome-wide H3K4me1 and H3K27ac patterns in mouse oocytes and pre-implantation embryos using low-input CUT&RUN (cleavage under targets and release using nuclease) with input as low as 50 cells. Both markers are enriched in distal regions and exhibit distinct sequence preferences and reprogramming dynamics in pre-implantation embryos. H3K27ac, a mark of active enhancers, is reprogrammed at the 2-cell stage, whereas H3K4me1 is remodeled at the 4-cell stage and overlaps with H3K27ac, coinciding with accessible chromatin regions. Interestingly, H3K4me1 and H3K27ac are co-localized in promoter regions, where they are mutually exclusive to H3K4me3. Enhancers are dynamically remodeled during maternal-to-zygotic transition (MZT). there are three enhancer types: active enhancers (H3K4me1/H3K27ac), primed enhancers (H3K4me1), and poised enhancers (H3K4me1/H3K27me3). Active enhancers increase significantly after zygotic genome activation. Further, super-enhancers are present across the genome and are mainly enriched in promoters. The specific motifs enriched by super-enhancers may be associated with the variations of gene expressions at different stages.

developmental biology↗

Stromal Gasdermin D-mediated Pyroptosis Drives Maladaptive CD4⁺ T-cell Remodeling in Tet2-Deficient Hematopoiesis

An inflammatory bone marrow microenvironment is increasingly recognized as critical in myeloid disease evolution, yet how stromal inflammation interfaces with adaptive immunity remains poorly defined. Here, we show that stromal pyroptosis drives mutation-specific myeloid expansion by coordinating monocytic remodeling and CD4 T-cell activation. Genetic ablation of gasdermin D in the bone marrow stroma suppressed stromal pyroptosis and attenuated Tet2-deficient myeloid expansion. Tet2 deficiency skewed monocyte and macrophage differentiation toward an activated, antigen-presenting state that interacted with pyroptotic stromal cells to promote expansion of a distinct CD4 T-cell population. These cells expressed canonical T follicular helper markers (Bcl6, Cxcr5, Il21, and Cd40l) together with interferon-responsive and tissue-interaction programs, consistent with an inflammation-adapted TFH-like state. CD40L produced by these cells reinforced the expansion of Tet2-deficient monocytes and macrophages, establishing a feed-forward stromal-immune circuit. Disruption of this axis through stromal gasdermin D deficiency or CD40L blockade attenuated myeloid expansion in vivo. Consistent with these findings, patients with isolated TET2 loss-of-function mutations exhibited CD4 T-cell skewing and CD40L+ T-cell-rich tertiary lymphoid structures in the bone marrow. Together, these data identify a pyroptosis-dependent stromal-immune axis that links early myeloid inflammation to maladaptive remodeling of adaptive immunity and reveals a context-dependent therapeutic vulnerability in Tet2-deficient hematopoiesis.

cancer biology↗

Histone H2BK120 ubiquitination modulates PRC1 activity and H2AK119ub deposition on nucleosomes

Polycomb group and Trithorax group complexes antagonistically regulate developmental gene expression, yet the mechanisms coordinating their interplay remain poorly understood. Here, we uncover a synergistic histone crosstalk in which H2BK120ub (histone H2B ubiquitination at lysine 120), a Trithorax-associated active mark, enhances Polycomb repressive complex 1 (PRC1) activity by directly binding specific PCGF subunits of PRC1 on the nucleosome surface, as shown in cryo-electron microscopy (cryo-EM) analysis. Beyond regulating enzymatic activity, H2BK120ub also modulates the competitive binding between the catalytic RNF2-BMI1 module and the RYBP subunit of noncanonical PRC1.4 complexes to nucleosomes, potentially restricting H2AK119ub (histone H2A ubiquitination at lysine 119) spreading to neighboring nucleosomes. In mouse embryonic stem cells, H2BK120ub directs the deposition of H2AK119ub within the gene bodies of a subset of developmental genes, which exhibit more rapid activation compared to canonical H3K4me3/H3K27me3 bivalent genes. These findings reveal a previously unrecognized mechanism that links active and repressive histone modifications, providing new insights into the intricate chromatin regulation of gene expression during development.

molecular biology↗

Z-RNA-ZBP1 axis drives Tau-mediated neurodegeneration

Although the causes of Tau aggregates vary, once Tau aggregates are formed, their neurotoxicity significantly contributes to neuronal death and cognitive decline in tauopathies, with Alzheimers disease (AD) being the most well-known example. Despite its central pathogenic role, however, effective therapeutic strategies targeting neurotoxicity of Tau remain poor. Here we demonstrate the pathogenic role of neuronal cell death in Tau-related neurodegeneration. Tau-expressing neurons undergo cell death through Z-DNA-binding protein 1 (ZBP1) activation triggered by endogenous Z-RNAs. These Z-RNAs are derived from reactivated transposable elements (TEs) that are typically silenced within heterochromatin. Tau aggregates show a strong affinity for H3K9me3-modified chromatin, effectively sequestering these epigenetic marks from Heterochromatin Protein 1 (HP1), thereby disrupting the condensation of constitutive heterochromatin. Clinically, an inverse correlation between ZBP1 expression levels in excitatory neurons and cognitive performance in AD patients was observed. Importantly, Zbp1 haploinsufficiency significantly ameliorated cognitive deficits in aged Tau-transgenic mice (24-month-old), highlighting the therapeutic potential of ZBP1 inhibition to strive against neurodegeneration in tauopathies.

neuroscience↗

Wnt-presenting materials sustain H3K14-acetylation in human skeletal stem cells for tissue engineering and bone repair

Engineering functional tissues for transplantation requires insight into epigenetic mechanisms that regulate stem cell fate. We have developed the Wnt-induced osteogenic tissue model (WIOTM), a platform that recapitulates human osteogenesis, and identified acetylation of histone H3 at lysine 14 (H3K14ac) as a critical epigenetic regulator in human skeletal stem cells (hSSCs). In WIOTM, localized Wnt signals drive asymmetric cell division (ACD), yielding a proximal hSSC with high H3K14ac and a distal daughter with reduced H3K14ac that migrates into the 3D collagen matrix and initiates osteogenic differentiation. Disrupting H3K14ac in hSSCs abrogates ACD and WIOTM formation. To test whether hSSCs maintain H3K14ac in vivo, we formed the WIOTM on Wnt-functionalized polymer bandages and transplanted them into calvarial defects. The WIOTM contributed to bone repair, and human cells adjacent to the bandages retained high H3K14ac despite the injury environment. These findings establish WIOTM as both a mechanistic and translational platform for regenerative medicine.

cell biology↗

Context-aware simulation enables systematic optimization of long-read mapping parameters

The performance of long-read mapping is critical yet highly sensitive to parameter choices. We present CycSim, a context-aware simulator that models sequence-context-dependent errors from empirical sequencing data, coupled with a Bayesian optimization framework for systematic parameter tuning. CycSim more accurately reproduces real error profiles than existing simulators, enabling reliable simulation-based optimization. The framework identified parameter configurations that achieved 2.78-fold faster mapping for data from the newly developed Cyclone platform, and consistently improved both mapping efficiency (8.14-32.65% faster) and structural variant calling accuracy (0.75-1.70% higher F1) across ONT, HiFi, and Cyclone datasets, providing a robust and generalizable foundation for analysis-goal-driven parameter refinement.

bioinformatics↗

Investigation of TRMT61B methyltransferase activity on mRNA and its effects on translation

Despite recent advances in technology to map RNA chemical modifications transcriptome-wide, the distribution of N{superscript 1}-methyladenosine (m{superscript 1}A) in mRNA remains contested, hindering a clear understanding of its function. Additionally, the enzyme(s) that installs the majority of reported mRNA m1A sites has yet to be identified. In this study, we characterized TRMT61B, an m1A methyltransferase known to methylate mitochondrial RNAs, but whose sequence preferences have been underexplored. By integrating cellular overexpression of TRMT61B and in vitro methylation of a synthetic pool of diverse human RNA sequences, we identified a preference for a YMRA consensus motif in single stranded RNA regions. In these experiments, TRMT61B methylated thousands of novel human mRNA sites, revealing activity on cytosolic mRNAs. We used these novel m1A-modifiable sequences to test the effects of m1A on translation of luciferase reporters and on ribosome recruitment to modified transcripts in the pool. We found that m1A addition can significantly affect translation and ribosome recruitment, but that these effects are vary by transcript. Taken together, our results can inform future studies of TRMT61B and mRNA, and emphasize that studies of m1A regulation of mRNA must be carried out and interpreted in a highly context-aware manner.

biochemistry↗

Complete and haplotype-resolved maps of genomic and epigenetic discordance in monozygotic twins

Telomere-to-telomere (T2T) genome assemblies are indispensable for accurate detection of genetic variation and for resolving complex repetitive regions. Monozygotic (MZ) twin pedigrees provide a powerful model to investigate de novo mutations (DNMs), however, comprehensive, haplotype-resolved analyses of structural variation (SV), allele-specific inheritance in complex regions, and DNA methylation in diploid human genomes remain limited. Here, we generated complete, haplotype-resolved T2T assemblies for two female twins (C33 and C35) from a Han Chinese pedigree by integrating complementary, state-of-the-art sequencing technologies. The resulting T2T-C33 and T2T-C35 assemblies are highly contiguous and complete, with Genome Continuity Inspector (GCI) scores of 74.94 (maternal) and 77.94 (paternal), and consensus quality values (QV) >75 (k = 21). We comprehensively cataloged 62 inter-twin single-nucleotide variants (SNVs), 15 small indels, and identified both shared and private DNMs, revealing nascent genomic divergence between the MZ twins. Focused interrogation of complex regions uncovered pronounced haplotype-specific length polymorphisms and structural heterogeneity within centromeric higher-order repeat (HOR) arrays. Notably, we observed extensive HOR copy-number variation between haplotypes, including a large copy-number difference on maternal chromosome 18, underscoring dynamic HOR array evolution even among genetically identical individuals. Concurrently, genome-wide DNA methylation profiling delineated allele-specific epigenetic variation that may contribute to phenotypic discordance. Together, these high-quality, diploid T2T genomes from a Han Chinese pedigree provide a valuable resource for population-aware genomics and reveal fine-scale, haplotype-specific divergence in MZ twins. Our results advance understanding of repeat dynamics, centromeric architecture, epigenetic variation and the spectrum of human genomic variation at single-base and structural scales.

genomics↗

Prolactin links psychological stress to psoriasis via a fibroblast-chemokine pathway

Psoriasis is a chronic inflammatory skin disease that forms a vicious cycle with psychological stress. Whether and how the hypothalamic-pituitary (HP) axis-mediated neuroendocrine system regulates psoriasis remains obscure. Here, we report elevated levels of the pituitary hormone prolactin (PRL) in both psoriasis patients and imiquimod (IMQ)-induced psoriasis mice. Mechanistically, PRL acts on dermal PRLR-expressing fibroblasts to promote the production of the chemokines CCL2 and CCL7, which then recruit monocytes/macrophages into psoriatic lesional skin, thereby activating local IL-17A-producing T cells. Accordingly, pharmacological targeting of PRL signaling inhibits the recruitment of monocytes/macrophages, decreases the frequency of IL-17A-producing T cells, and alleviates IMQ-induced psoriasis in mice. In summary, our results delineate a mechanism by which the neuroendocrine hormone PRL aggravates psoriasis and highlight a potential therapeutic strategy of inhibiting PRL-PRLR signaling, particularly in psoriasis patients experiencing psychological stress.

immunology↗

Efineptakin alfa (NT-I7) improves overall survival and induces tertiary lymphoid structures in murine lung tumors

Tertiary lymphoid structures (TLSs) are emerging as good predictive biomarkers of response to cancer immunotherapy. However, therapeutic strategies to induce these structures are currently limited. We evaluated the therapeutic benefit of efineptakin alfa (NT-I7), a long-acting form of IL-7, and its ability to induce TLSs in a murine lung tumor model. NT-I7 improved overall survival in tumor-bearing mice. It also increased the abundance of T, B, dendritic cells, and stem-like CD8 T cells and promoted the formation of immune aggregates in the tumor microenvironment (TME). Stem-like CD8 T cells were preferentially located in the immune aggregates. Spatial transcriptomic analyses of the TME further demonstrated that the immune aggregates induced by NT-I7 included TLSs with enrichment of Cd274 (PD-L1) transcripts and genes involved in antigen processing and presentation. Upregulation of Cd274 in the TLSs may provide opportunities for synergy between NT-I7 and PD-1-targeted immunotherapy. STATEMENT OF SIGNIFICANCEThis study demonstrates the ability of efineptakin alfa (NT-I7) to potentially augment the clinical efficacy of cancer immunotherapy by inducing tertiary lymphoid structures in the tumor microenvironment.

immunology↗

N6-methyladenosine promotes temozolomide resistance through non-canonical regulation of mRNA stability in glioblastoma cells

N6-methyladenosine (m6A) is a critical regulator of mRNA processing and function, impacting nearly every step of the mRNA lifecycle. Changes in m6A status have been implicated in many different types of cancer, including glioblastoma where acquired resistance to temozolomide remains a major clinical challenge. We established glioblastoma cell culture models of acquired temozolomide resistance and analyzed the role of m6A in controlling resistance-associated pathways. We show that m6A stabilizes key genes and pathways promoting temozolomide resistance in glioblastoma, including MGMT, the enzyme that repairs primary temzolomide-induced DNA damage, and PI3K/Akt signaling, a major driver of chemoresistance. Pharmacological inhibition of the m6A methyltransferase METTL3 destabilizes MGMT and other critical mRNAs, restoring temozolomide sensitivity. Collectively, our results suggest that genes associated with temozolomide resistance are stabilized by m6A methylation, even as the majority of the transcriptome remains subject to m6A-mediated mRNA decay. Moreover, these data highlight METTL3 inhibition as a promising therapeutic approach to overcoming temozolomide resistance in glioblastoma.

molecular biology↗

Rare Subset of T Cells Form Heterotypic Clusters with Circulating Tumor Cells to Foster Cancer Metastasis

The immune ecosystem is central to maintaining effective defensive responses. However, how immune cells in the periphery blood interact with circulating tumor cells (CTCs) - seeds of metastasis - remains largely understudied. Here, our analysis of the blood specimens (N=1,529) from patients with advanced breast cancer revealed that over 75% of the CTC-positive blood specimens contained heterotypic CTC clusters with CD45+ white blood cells (WBCs). Detection of CTC-WBC clusters correlates with breast cancer subtypes (triple negative and luminal B), racial groups (Black), and decreased survival rates. Flow cytometry and ImageStream analyses revealed diverse WBC composition of heterotypic CTC-WBC clusters, including overrepresented T cells and underrepresented neutrophils. Most strikingly, a rare subset of CD4 and CD8 double positive T (DPT) cells showed an up to 140-fold enrichment in the CTC clusters versus its frequency in WBCs. DPT cells shared part of the profiles with CD4+ T cells and others with CD8+ T cells but exhibited unique features of T cell exhaustion and immune suppression with higher expression of TIM-3 and PD-1. Single-cell RNA sequencing and genetic perturbation studies further pinpointed the integrin VLA4 (4{beta}1) in DPT cells and its ligand VCAM1 in tumor cells as essential mediators of heterotypic WBC-CTC clusters. Neoadjuvant administration of anti-4 (VLA4) neutralizing antibodies markedly blocked CTC-DPT cell clustering and inhibited metastasis for extended survival in preclinical mouse models in vivo. These findings uncover a pivotal role of rare DPT cells with immune suppressive features in fostering cancer dissemination through direct interactive clustering with CTCs. It lays a foundation for developing innovative biomarkers and therapeutic strategies to prevent and target cancer metastasis, ultimately benefiting cancer care. Brief summaryOur findings uncover a fostering role of immune-suppressive T cells in contact with circulating tumor cells and identify therapeutic approaches to eliminate devastating cancer metastasis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=191 SRC="FIGDIR/small/646421v1_ufig1.gif" ALT="Figure 1"> View larger version (67K): org.highwire.dtl.DTLVardef@13b7862org.highwire.dtl.DTLVardef@15c97b2org.highwire.dtl.DTLVardef@1eb4fd2org.highwire.dtl.DTLVardef@1c588e1_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Comparative spatiotemporal single cell transcriptomes reveal rewiring of pre-existing regulations during emergence of Kranz anatomy in C4 grasses

Many of the worlds most productive food and bioenergy crops use C4 photosynthesis, which have high photosynthetic efficiency due to a Kranz anatomy-based CO2 concentrating mechanism. Here, we took a comparative transcriptomics approach using single cell spatial transcriptomes of leaf primordia for maize (Zea mays) and single cell RNA-seq (scRNA-seq) atlases of corresponding leaf tissues for three C4 species (Zea mays, Sorghum bicolor, Setaria viridis) and one C3 rice (Oryza sativa) to study regulatory networks involved in the development and evolution of Kranz anatomy. We show that the formation of Kranz anatomy involves extensive recruitment and modification of pre-existing regulatory modules, especially the SHR-SCR module and the auxin signaling pathway. Members of the INDETERMINATE DOMAIN (IDD) family transcription factors, including IDD7 and IDDP1, contribute to the modification of the involved modules. These extensive recruitment and modification of existing genetic regulatory programs underlie the repeated emergence of C4 photosynthesis during evolution.

plant biology↗

Rejuvenating aged osteoprogenitors for bone repair

Aging is marked by a decline in tissue regeneration, posing significant challenges to an increasingly older population. Here, we investigate age-related impairments in calvarial bone healing and introduce a novel two-part rejuvenation strategy to restore youthful repair. We demonstrate that aging negatively impacts the calvarial bone structure and its osteogenic tissues, diminishing osteoprogenitor number and function and severely impairing bone formation. Notably, increasing osteogenic cell numbers locally fails to rescue repair in aged mice, identifying the presence of intrinsic cellular deficits. Our strategy combines Wnt-mediated osteoprogenitor expansion with intermittent fasting, which leads to a striking restoration of youthful levels of bone healing. We find that intermittent fasting improves osteoprogenitor function, benefits that can be recapitulated by modulating NAD+ dependent pathways or the gut microbiota, underscoring the multifaceted nature of this intervention. Mechanistically, we identify mitochondrial dysfunction as a key component in age-related decline in osteoprogenitor function and show that both cyclical nutrient deprivation and Nicotinamide mononucleotide rejuvenate mitochondrial health, enhancing osteogenesis. These findings offer a promising therapeutic avenue for restoring youthful bone repair in aged individuals, with potential implications for rejuvenating other tissues.

cell biology↗

Telomere-to-telomere African wild rice (Oryza longistaminata) reference genome reveals segmental and structural variation

Rice (Oryza sativa) is one of the most important staple food crops worldwide, and its wild relatives serve as an important gene pool in its breeding. Compared with cultivated rice species, African wild rice (Oryza longistaminata) has several advantageous traits, such as resistance to increased biomass production, clonal propagation via rhizomes, and biotic stresses. However, previous O. longistaminata genome assemblies have been hampered by gaps and incompleteness, restricting detailed investigations into their genomes. To streamline breeding endeavors and facilitate functional genomics studies, we generated a 343-Mb telomere-to-telomere (T2T) genome assembly for this species, covering all telomeres and centromeres across the 12 chromosomes. This newly assembled genome has markedly improved over previous versions. Comparative analysis revealed a high degree of synteny with previously published genomes. A large number of structural variations were identified between the O. longistaminata and O. sativa. A total of 2,466 segmentally duplicated genes were identified and enriched in cellular amino acid metabolic processes. We detected a slight expansion of some subfamilies of resistance genes and transcription factors. This newly assembled T2T genome of O. longistaminata provides a valuable resource for the exploration and exploitation of beneficial alleles present in wild relative species of cultivated rice.

genomics↗

Dimensionality Reduction and Denoising of Spatial Transcriptomics Data Using Dual-Channel Masked Graph Autoencoder

Recent advances in spatial transcriptomics (ST) technology allow researchers to comprehensively measure gene expression patterns at the level of individual cells or even subcellular compartments while preserving the spatial context of their tissue. Spatial domain identification is a critical task in analyzing the ST data. However, effectively capturing distinctive gene expression features and relationships between genes poses a significant challenge. We develop a graph self-supervised learning method STMask for the analysis and exploration of the ST data. STMask combines the masking mechanism with a graph autoencoder, compelling the gene representation learning channel to acquire more expressive representations. Simultaneously, it combines the masking mechanism with graph self-supervised contrastive learning methods, pulling together the embedding distances between spatially adjacent points and pushing apart the representations of different clusters, allowing the gene relationship learning channel to learn more comprehensive relationships. The applications of STMask to four ST datasets demonstrate that STMask outperforms state-of-the-art methods in various tasks, including spatial clustering and trajectory inference. Source code is available at https://github.com/donghaifang/STMask. Author summarySpatial Transcriptomics (ST) is an emerging transcriptomic sequencing technology aimed at revealing the spatial distribution of gene expression and cell types within tissues. This method enables the acquisition of gene expression profiles at the level of individual cells or spots within the tissue, uncovering the spatial expression patterns of genes. However, accurately identifying spatial domains in ST data remains challenging. In our study, we introduce STMask, a self-supervised learning method that combines a dual-channel masked graph autoencoder with masking and contrastive learning. Our work contributes primarily in two aspects: (1) We propose a novel graph self-supervised learning method (STMask) specifically tailored for the analysis and research of ST data, which enhances the ability to capture the unique features of gene expression and spatial relationships within tissues. (2) Through comprehensive experiments, STMask provides valuable insights into biological processes, particularly in the context of breast cancer. It identifies enrichment of various differentially expressed genes in tumor regions, such as IGHG1, which can serve as effective targets for cancer therapy.

genomics↗