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Chen, G.

Publications and source records attributed to Chen, G..

At least 19 recordsLinked to original sources

Localized Chromatin Rewiring Shapes Rhythmic Transcription within a Stable 3D Genome in Rice

How spatial genome architecture coordinates rhythmic gene transcription across scales in plants remains poorly understood. Here, we integrated bridge linker Hi-C (BL-Hi-C), H3K9ac ChIP-seq and RNA-seq at six time points across a 24-h circadian cycle in rice. While global higher-order structure was largely invariant, with 84.5% of A/B compartments and over 95% of topologically associating domains (TADs) conserved across all time points, we identified 557 dynamic compartment transitions coupled to changes in active chromatin marks. Within this stable structural scaffold, 35.8% of TADs containing clustered loci of multiple rhythmic genes with synchronized expression phases. In contrast, fine-scale intradomain contacts and chromatin loops exhibited pronounced temporal plasticity. Chromatin interactions connected rhythmic genes with diverse expression phases. Myb-binding motifs were enriched at chromatin interaction anchors at dawn and early day (ZT0 and ZT4). Together, our findings demonstrate that localized chromatin rewiring occurs within relatively stable architectural frameworks, providing a spatiotemporal context for circadian gene regulation in rice.

genomics↗

Integrated Multiomics Reveals Intergenerational Brain Sensory System Remodeling Induced by Parental Intermittent Fasting

Intermittent fasting (IF) is increasingly recognized as a potent modulator of metabolic health, but its effects on brain function across generations remain poorly understood. Here, we show that parental IF, administered to both mothers and fathers before mating, is associated with coordinated molecular remodeling in the cerebral cortex of fathers and their offspring, with shared molecular signatures identified between these generations and a pronounced enrichment of sensory-associated pathways. Using whole-genome bisulfite sequencing, transcriptomic profiling, and proteomic analysis, we found that IF elicited widespread cortical epigenetic remodeling in fathers, accompanied by transcriptional and protein-level changes enriched for olfactory, taste, synaptic, and neurometabolic pathways. Strikingly, related molecular signatures were detected in F1 offspring that had never been directly exposed to fasting, consistent with intergenerational transmission of IF-associated cortical remodeling. Offspring responses were sex dependent, with female and male progeny exhibiting distinct patterns of DNA methylation, gene expression, and protein abundance. Integrated multiomic analyses identified conserved candidate networks involved in sensory perception, glutamatergic signaling, synaptic organization, intracellular trafficking, cytoskeletal regulation, and stress-response pathways. Together, these findings identify sensory-associated cortical remodeling as a prominent molecular feature associated with parental IF and reveal persistent, sex-dependent molecular alterations in the offspring brain.

genomics↗

AMPK-dependent brain-wide norepinephrine release promotes recovery from metabolic coma in mice

Coma is a pathological brain state characterized by loss of consciousness. How the brain recovers from coma remains largely unknown. Using mouse models of metabolic coma, we identified an endogenous neuromodulatory pathway that actively promotes coma recovery. In mice subjected to hypoglycemic coma, hypoglycemia triggered AMPK-dependent excitation of nucleus tractus solitarius (NTS) neurons, which activated locus coeruleus (LC) norepinephrine neurons through a glutamatergic NTS-LC circuit. LC activation drives widespread norepinephrine release across cortical and subcortical regions, thereby promoting post-coma arousal. Notably, coma-associated brain-wide norepinephrine release was unconventional in both scale and duration, with a magnitude approximately 10-fold higher than physiological norepinephrine release during sleep-wake cycles. This neuromodulatory process also operated during hypercapnic coma. Vagus nerve stimulation accelerated coma recovery by engaging this endogenous anti-coma mechanism. Our findings uncover an AMPK-dependent brainstem circuit that actively restores arousal from metabolic coma, revealing a neural defense strategy against profound metabolic stress.

neuroscience↗

Two functionally distinct amyloid-β intermediates link aggregation pathways to pathology in Alzheimer's disease

Neurotoxic intermediates formed during amyloid-{beta}(A{beta}) aggregation are thought to drive Alzheimer's disease, yet their rarity and transient nature have obscured their identity and formation pathways in the human brain. Here, we combine super-resolution microscopy and single-molecule functional imaging with kinetic modelling to classify A{beta} intermediates according to their membrane-disrupting activity and connect their damaging effects to the aggregation pathways that generate them. Applying this framework to recombinant A{beta}42, an Alzheimer's knock-in mouse model and human Alzheimer's brain tissue, we find two functionally distinct intermediate populations present across all systems. They form through separate aggregation routes and differ in their neurotoxicity, abundance and susceptibility to inhibition. Both damage neurons and glia, but only one converts into plaques. Suppressing these intermediates pharmacologically in mice reduces plaque burden, attenuates astrogliosis and improves cognition. Our findings connect model systems with human pathology and identify intermediate formation pathways as actionable therapeutic targets across protein-misfolding disorders.

biophysics↗

Near-infrared optoacoustic modulation of the blood-brain barrier permeability using size-tuned hyperbranched gold nanoconstructs

The blood-brain barrier (BBB) constitutes a major bottleneck for the systemic delivery of most therapeutic agents to the central nervous system. Here, we report near-infrared reversible optoacoustic modulation of the BBB permeability (NIR-ROAMBBB), leveraging endothelial tight junction targeting hyperbranched gold nanoconstructs (HBGNCs) to amplify localized optoacoustic transduction under femtosecond laser excitation. We first synthesized HBGNCs with tunable particle sizes (62-150 nm) and consistent branch morphologies via a seed-mediated growth approach, and uncovered a non-monotonic relationship between particle dimension and optoacoustic output, where the 62 nm HBGNCs generated nearly twofold stronger optoacoustic signal than gold nanorods and gold nanostars under matched excitations. Conjugation with BV11 antibodies against junctional adhesion molecule A increased HBGNC endothelial association and cerebral accumulation, enabling focal and fluence-dependent transient BBB opening (3-6 h) under 800 nm femtosecond pulsed laser excitation, as validated by in vitro trans-endothelial electrical resistance measurements, ex vivo Evans blue extravasation staining, and in vivo NIR imaging. Featuring deep tissue penetration of NIR light, robust optoacoustic conversion of HBGNCs, and negligible femtosecond laser-induced photothermal damage, this non-invasive strategy enables precise focal modulation of BBB permeability and potential drug delivery.

bioengineering↗

Blood-Mediated Opto-Acoustic Stimulation of Brain Cortex at Sub-millimeter Precision

Direct modulation of neural activity with high spatiotemporal precision is a cornerstone in experimental neuroscience. Here, we present a blood-mediated optoacoustic stimulation (BOAS) approach that utilizes blood as an endogenous transducer for brain stimulation. By delivering 532-nm nanosecond pulsed laser to the cortex, we demonstrate that the absorption of hemoglobin generates sufficient acoustic pressure to trigger neuronal activity. By integrating BOAS with calcium imaging in GCaMP6f-expressing mice, localized neuronal responses were observed. Quantitative analysis reveals that BOAS produces responses comparable to natural visual stimulation and is significantly more efficient than the photothermal stimulation. Furthermore, we show that the response is dose-dependent. At high energy doses, BOAS induces cortical spreading depression. Histological evaluation confirmed that the brain maintains tissue integrity even under these stimulation parameters. Together, this work establishes a versatile method for precise brain stimulation as an alternative method for stimulating neuron at cortex.

bioengineering↗

Hidden genetic diversity in 320 nearly-complete East Asian genome assemblies

East Asian populations, representing over 20% of the global population, remain critically underrepresented in human genomic studies, limiting our understanding of population-stratified genetic variation and its implications for health and disease. Here we present the first phase of the Asian Pan-Genome project (APG), comprising 320 nearly complete, fully phased haploid genome assemblies from 160 East Asian individuals. These assemblies achieve unprecedented quality, with an average contig N50 of 144.3 megabase pairs and an average quality value of 64.5. Leveraging these superior assemblies, we reveal previously uncharacterized diversity in human repeatome, including population-stratified patterns in centromere satellites and rDNA arrays. Compared to existing global human genome assemblies, the newly generated genomes supplement 152 million base pairs of novel sequences, 355 gene gains, 18,300 structural variation loci and 26 large euchromatic inversions missing from current human pangenomes. We perform population stratification analyses of structural variations, and further resolve the structural haplotypes of complex genomic regions such as Major Histocompatibility Complex and Survival Motor Neuron loci across global pangenomes, exemplifying tandem-duplicate and inversion-rich complex locus architectures in the human genome, respectively. This resource provides a critical foundation for human genetic studies, especially for East Asian populations, promoting more accurate variant discovery, reducing bias, and ultimately advancing the equity and efficacy of genomic medicine.

genomics↗

Tracing the 'Panda of the Sea': Species-Specific qPCR Assays for eDNA Monitoring of Critically Endangered Bahaba taipingensis in the Pearl River Estuary

Chinese Bahaba (Bahaba taipingensis, Sciaenidae) is a Critically Endangered, Grade I state-protected marine fish in China. Reliable, non-invasive monitoring tools are urgently needed to inform conservation and restocking efforts. We developed and validated three TaqMan probe-based qPCR assays targeting mitochondrial 12S rRNA, ND5, and control region (D-loop) loci for species-specific detection of B. taipingensis. Primer-probe sets were designed from complete mitochondrial genomes and evaluated in silico against GenBank and in vitro against tissue DNA from B. taipingensis and closely related sciaenids, plus positive eDNA samples; sensitivity was quantified using serial dilutions of synthetic target DNA. All three assays showed high specificity and consistent amplification; 12S rRNA assay (Bhb_12S) was selected for field screening based on superior low-copy sensitivity and minimal by-products. We applied the Bhb_12S assay to 414 seawater samples collected from 23 sites in western Hong Kong during 2025 surveys, detecting B. taipingensis eDNA in the September samples (0.71-2.85 copies per L; mean 2.05), with positive detections confirmed by Sanger sequencing. Overall, these validated qPCR assays provide a robust molecular toolkit for non-invasive monitoring of B. taipingensis and will aid conservation planning, restocking evaluation, and long-term biodiversity assessments in the Pearl River Estuary and adjacent coastal waters.

ecology↗

Temporal decoding of blood flow derived mechanical cues driving liver regeneration

Liver regeneration is initiated by rapid vascular changes, yet how blood flow-derived mechanical cues are decoded by liver sinusoidal endothelial cells (LSECs) remains unclear. Here, we found that partial hepatectomy generates temporally distinct mechanical cues in vivo, with a transient rise in shear stress followed by progressive sinusoidal dilation and endothelial stretch. To dissect these forces, we developed a liver regeneration chip that reconstructs sinusoidal architecture and enables independent or coupled manipulation of shear stress and mechanical stretch. Shear-dominant, stretch-dominant, and coupled mechanical modalities induce divergent LSEC regenerative programs involving extracellular matrix remodeling, cell-cycle regulation, cytoskeletal organization, and angiocrine signaling. Mechanistically, force-specific pathways, including Wnt, HIF-1, NF-{kappa}B, and Piezo1-associated signaling, mediate these outputs. Inhibition of these pathways after partial hepatectomy impairs hepatocyte proliferation and survival. These findings reveal that LSECs temporally decode blood flow-derived mechanical forces into distinct regenerative outputs, establishing endothelial mechanotransduction as an upstream regulator of liver regeneration. HIGHLIGHTS{blacksquare} Partial hepatectomy decouples transient shear from progressive stretch in vivo. {blacksquare}A liver regeneration chip recreates structure and distinct mechanical modalities in sinusoids. {blacksquare}Distinct mechanical modalities encode divergent LSEC regenerative programs. {blacksquare}Force-specific LSEC mechanotransduction supports hepatocyte proliferation and survival.

bioengineering↗

IL-21-producing peripheral helper T cells associate with autoimmune bile duct injury in biliary atresia

BackgroundBiliary atresia (BA) is a severe neonatal liver disease characterized by progressive fibrosis and bile duct obliteration. ObjectiveAlthough immune dysregulation is implicated in the pathogenesis of BA, the specific mechanisms driving bile duct injury remain incompletely understood. This study aimed to characterize tertiary lymphoid structures (TLSs) within extrahepatic biliary remnants (EBRs), identify their cellular mediators, and evaluate the therapeutic potential of targeting IL-21 receptor signaling. DesignWe performed integrated bulk RNA sequencing, single-cell RNA sequencing, spatial transcriptomics, multiplex immunohistochemistry, and flow cytometry on clinical samples from BA patients and non-BA cholestatic controls. TLS maturation was assessed by CD23 immunohistochemistry in EBRs from 148 BA patients and correlated with clinical parameters. Anti-IL-21R antibody treatment was evaluated in a rhesus rotavirus-induced BA mouse model, with treatment initiated on day 4 post-infection. ResultsTLSs were identified in BA EBRs with significantly higher prevalence than in matched liver tissues. Mature TLSs containing CD23 germinal centers were associated with elevated serum matrix metalloproteinase-7, more advanced hepatic fibrosis, and localized autoantibody deposition on injured bile ducts. Single-cell profiling revealed expanded CD4+ T peripheral helper (Tph) cells expressing IL-21 and CXCL13 within TLS-containing EBRs. Tph cells were enriched in peripheral blood of BA patients compared to non-BA cholestatic controls (P = 0.0025), and serum IL-21 was significantly elevated (P < 0.0001). Post-infection IL-21R blockade in the mouse model reduced jaundice incidence, improved weight gain, prevented extrahepatic biliary obstruction, and significantly improved long-term survival. ConclusionTLSs in BA extrahepatic biliary remnants harbor expanded Tph cells associated with IL-21-mediated B cell activation and bile duct injury. IL-21R blockade ameliorated disease in a murine BA model, identifying the IL-21/IL-21R axis as a potential therapeutic target warranting further investigation. Key MessagesO_ST_ABSWhat is already known on this topicC_ST_ABSImmune dysregulation contributes to biliary atresia (BA), with documented lymphocyte infiltration and defective B cell tolerance. However, the cellular mechanisms linking local immune activation to bile duct injury are unclear, and the roles of organized lymphoid structures and specific CD4 T cell subsets in orchestrating local humoral responses have not been characterized. What this study addsThis study demonstrates that mature tertiary lymphoid structures in extrahepatic biliary remnants are associated with disease severity markers and localized bile duct injury in BA. We identify T peripheral helper cells as an expanded IL-21-producing CD4 T cell population within these structures, and show that post-infection IL-21 receptor blockade prevents biliary obstruction and improves survival in a murine BA model. How this study might affect research, practice or policyThese findings identify the IL-21/IL-21R signaling axis as a candidate therapeutic target in BA warranting further preclinical and translational investigation. TLS maturation status in biliary remnants and serum autoantibody levels may serve as potential biomarkers of disease severity, meriting prospective evaluation in clinical cohorts.

immunology↗

AlfaDAX-Derived ActRIIA/B Antibody with Semaglutide Enhances Fat Loss and Improves Weight-Loss Quality in DIO Mice

GLP-1 receptor agonists achieve weight loss but are associated with clinically significant reductions in lean mass. Activin type II receptors (ActRIIA and ActRIIB) mediate signaling of myostatin and activin A, both of which negatively regulate muscle growth, suggesting that dual blockade of these receptors may preserve or increase lean mass while promoting fat loss. In this study, we developed anti-ActRIIA/B antibodies using AI-driven platforms (AlfaDAX) and selected the lead candidate AB130-165 based on in vitro binding, functional blocking, and developability assessments. Compared with a laboratory-prepared bimagrumab analog, AB130-165 exhibited potent dual inhibition of ActRIIA/B signaling, with a 9.5-fold higher functional blocking activity against activin A-induced SMAD signaling and 1054-fold improvements in binding affinity for ActRIIA (KD = 0.204 pM), 10-fold for ActRIIB (KD = 0.243 pM), respectively. In diet-induced obese mice, combination therapy with AB130-165 and semaglutide resulted in a 33.4% body weight reduction, which was superior to semaglutide monotherapy (-24.3%) and the bimagrumab combination group (-25.5%). Moreover, the combination significantly improved body composition, reducing fat mass percentage by 77.8% (vs. 65.0% in the bimagrumab combination group) and increasing the lean-to-body weight ratio to 67.3% (vs. 62.3%), demonstrating superior fat loss with better preservation of lean mass. Collectively, these findings establish AB130-165 as a differentiated anti-ActRII antibody that enables high-quality weight loss, and its combination with semaglutide shows superior efficacy over bimagrumab-based regimens. With favorable developability and potential for long-acting subcutaneous administration, AB130-165 represents a promising next-generation therapeutic candidate for obesity and muscle-sparing weight management.

pharmacology and toxicology↗

CatESO: Differentiable Enzyme Sequence Optimization Guided by Substrate-Aware kcat Prediction

Enzymes drive biological chemistry and offer greener routes to chemicals, materials and medicines, yet their broader use as biocatalysts is often limited by insufficient catalytic turnover. Improving turnover is hard: measured rate constants are scarce and protein sequence space is vast. Deep-learning models now predict the turnover number, kcat, with growing accuracy, but they are typically applied after sequence generation to score or filter candidates, which separates the kinetic objective from the design itself. To bridge the gap between sequence generation and kinetic evaluation, we introduce CatESO, a differentiable sequence optimizer that enables direct, gradient-guided design of substrate-specific catalytic turnover. By backpropagating through a cross-modal kcat predictor under continuous sequence relaxation, CatESO co-optimizes predicted catalytic activity, evolutionary plausibility and structural integrity in one end-to-end framework, using ESM-2 and ESMFold to keep designs evolutionarily plausible and foldable. Across seven stringent out-of-distribution enzymes spanning EC classes 1-7, CatESO raised model-predicted kcat for the vast majority of designs, with a median predicted fold change of 1.52 while every variant retained a pLDDT above 70. Against RFdiffusion3-LigandMPNN pipeline and ZymCtrl, CatESO struck a better balance between predicted activity and structural confidence. By making substrate-conditioned kinetic objectives differentiable, CatESO carries differentiable protein design beyond structure- and binding-centred goals to enzyme catalytic function, giving a general route to function-oriented enzyme engineering.

biochemistry↗

Region-specific molecular regulatory programs define epithelial identity, progenitor states, and mucus homeostasis in human distal airways

Small distal airways differ from proximal large airways in structure, airflow dynamics, and epithelial composition, and represent a central site of muco-obstructive lung disease pathogenesis. However, due in part to their inaccessibility, the molecular mechanisms that establish regional epithelial identity and govern mucociliary defense in distal airway epithelia remain poorly defined. Here, we integrate transcriptomic, secretomic, and chromatin accessibility analyses of matched primary human large and small airway epithelial cultures to define region-specific regulatory networks. We identify distal airway-specific transcriptional and chromatin programs required for maintaining epithelial identity and mucus homeostasis. Loss of NKX2-1 impairs distal airway secretory cell (DASC) differentiation and shifts mucus properties toward a disease-associated state. Lineage-resolved organoid assays identify an NKX2-1-high distal airway basal cell population with hybrid basal-secretory features as a selective progenitor for DASCs. Collectively, these findings establish a molecular framework for distal airway epithelial biology and define mechanisms regulating region-specific mucociliary host defense.

Cell Biology↗

A Tripartite Map of the Ventromedial Prefrontal Cortex

The ventromedial prefrontal cortex (VMPFC) has been repeatedly implicated in affect, valuation, and social cognition, yet how these diverse functions are organized within a single cortical territory has remained unresolved. Here, we integrate large-scale meta-analysis, individual-level task fMRI, artificial neural-network encoding models, and multimodal connectivity analyses to reveal the internal functional architecture of the human VMPFC. Across four complementary studies, we identify a robust tripartite organization along the anterior-posterior axis, comprising posterior affective, middle valuation, and anterior social functional motifs. Connectivity fingerprinting demonstrates that each motif is preferentially embedded within distinct large-scale brain networks, providing a mechanistic account of VMPFC functional specialization. This organization is reproducible at the level of individual subjects, generalizes to naturalistic stimuli, extends across development, and shows cross-species correspondence with non-human primates and multiple neurobiological markers. Together, these findings resolve a long-standing organizational question and establish a biologically grounded framework for interpreting VMPFC function.

neuroscience↗

Helminth infection induces RELMa-dependent adipose tissue transcriptional reprogramming and protection against diet-induced obesity

Obesity, a rising epidemic in the United States, is causally associated with adipose tissue inflammation, therefore targeting this immune dysfunction offers promising therapeutic avenues. Chronic helminth infection can prevent obesity pathogenesis but there remain opportunities to determine the immune factors that mediate protection and whether long-term protection is associated with changes in the visceral adipose tissue. We optimized a mouse model of western diet-induced obesity and investigated if transient helminth infection was protective through the immunoregulatory protein RELM. Wild-type (WT) or RELM knockout (KO) C57BL/6J mice were fed a western diet of high glucose and high fat followed by infection with helminth Nippostrongylus brasiliensis, which infects the lung and small intestine but is cleared within two weeks. Infection attenuated weight gain and improved glucose tolerance even after the parasite was expelled in WT but not RELM deficient mice. This protection was associated with reduced adipocyte hypertrophy in WT mice. Adipose tissue bulk RNA sequencing and digital cell quantification indicated that RELM promoted enrichment of eosinophils and M2 macrophages and upregulated pathways associated with fatty acid oxidation, mitochondrial function, and thermogenesis, whereas RELM deficiency led to pro-inflammatory, fibrotic, and lipid accumulation transcriptional profiles. Specific genes that were changed with infection and RELM deficiency included collagen and serpin genes associated with tissue remodeling and fibrosis, and changes within the adipose tissue was confirmed by immunofluorescent staining. Together, these findings establish that helminth-induced RELM critically protects against western diet-driven obesity and associated adipose transcriptional reprogramming and tissue remodeling.

immunology↗

Distinguishing Photoacoustic and Photothermal Neuron Stimulation Through Quantitative Mapping Spatiotemporal Field Evolution

Neuromodulation is a rapidly advancing strategy for modulating brain function and treating neurological disorders, yet the mechanisms of optical neural stimulation remain incompletely understood. A central challenge is that photoacoustic (PA) and photothermal (PT) effects are typically generated simultaneously and evolve on overlapping spatial and temporal scales, making their contributions to neuronal activation difficult to distinguish. Here, we overcome this limitation by integrating two carbon-based emitters with a spatial-offset pump-probe imaging platform to distinguish PA and PT neuromodulation through direct mapping of spatiotemporal field evolution. The two emitters produce nearly identical thermal fields while exhibiting a 26-fold difference in acoustic output, enabling decoupled comparison of thermal and acoustic contributions. To directly characterize the physical fields, we establish a spatial-offset pump-probe imaging system capable of visualizing both temperature and pressure evolution, confirming matched thermal profiles between the two emitters. Neuronal stimulation experiments further show that neurons are markedly more responsive to PA stimulation than to PT stimulation. Beyond resolving a longstanding mechanistic question, this work demonstrates the enhanced efficiency of PA stimulation and provides general guidance for designing high-performance optical neural interfaces.

neuroscience↗

Pathology-Targeted EP4 Agonism Reverses Fibrosis in a Rat Model of DMD

Duchenne muscular dystrophy (DMD) presents a critical therapeutic gap in adolescent patients, where extensive fibro-fatty muscle replacement and depletion of the regenerative niche render existing interventions insufficient. Prostaglandin E2 signaling through the EP4 receptor stimulates bone and muscle regeneration and repair, but systemic off-target effects have limited the clinical translation of EP4 agonism in diseases such as DMD. We therefore evaluated irodanoprost (IROD), a bone-targeted prodrug of an EP4-selective agonist, in a DMD rat model, comparing early- and late-intervention cohorts. In adolescent rats, 8 weeks of treatment reduced body weight deficit by 41.4% and restored hindlimb muscle mass and maximum tetanic force to wild-type levels. IROD dose-dependently inhibited fibro-adipogenic progenitor differentiation into -SMA myofibroblasts, facilitating active resolution of established fibrosis below pre-treatment baseline. This was accompanied by re-activation of a synchronized regenerative program marked by clustered eMHC fibers, restoring the total myofiber pool to wild-type levels. A strong linear correlation between intramuscular fat reduction and fibrosis resolution suggests that MRI-based fat imaging may serve as a non-invasive surrogate for monitoring anti-fibrotic efficacy. The efficacy of IROD is likely aided by the fact that while it selectively distributes to bone in healthy animals, we observed markedly enhanced accumulation of the drug in dystrophic muscle. These findings establish IROD as a pathology-targeted approach capable of resolving the fibro-fatty niche and restoring regenerative capacity in advanced DMD. SummaryPathology-targeted EP4 agonism resolves established fibrosis and restores myofiber regeneration in a rat model of adolescent Duchenne dystrophy. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=104 SRC="FIGDIR/small/728674v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@20447dorg.highwire.dtl.DTLVardef@70929dorg.highwire.dtl.DTLVardef@a99628org.highwire.dtl.DTLVardef@1c158f4_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Label-free 3D virtual histology of human formalin-fixed paraffin-embedded (FFPE) prostate needle biopsies with propagation-based phase-contrast micro-CT (PBCT)

For over a century, the goal of estimating clinical outcome from tumor biopsies has been based on histomorphology of 2D tissue slices that represent a small fraction of collected samples. Its power derives from histologys 1) unbiased representation of cell types, 2) subcellular resolution that allows the characterization of health and disease states across cell types, and 3) multi-millimeter fields of view that allow assessment of tumor heterogeneity. Histologys dependence upon physical slices, however, limits assessment of 3-dimensional cellular volumes and tissue architecture. Here, we used propagation-based phase-contrast micro-CT (PBCT) to create 3D histological images of residual formalin-fixed, paraffin-embedded (FFPE) prostate needle biopsies. The resulting isotropic, grey-scale, 0.5 micron voxel matrices were used to explore the potential of for the 3D virtual histology to distinguish diagnostic categories including benign prostatic tissue and prostatic adenocarcinoma of Gleason patterns 3, 4, and 5. Maximum intensity projections of stacks of digital slices totaling 5 microns "slices" allowed the study of virtual sections corresponding to actual serial H&E-stained sections of tissue cut after micro-CT imaging. Like histology, our PBCT reconstructions allowed us to distinguish between non-infiltrative and undulating glands of benign prostatic tissue, infiltrative round glands of Gleason pattern 3, cribriform structures of Gleason pattern 4, and comedonecrosis of Gleason pattern 5. Unlike histology, micro-CT allowed us to further probe 3D tissue architecture in volumetric context. User-friendly exploration of sample volumes was achieved using a customized Neuroglancer multiplanar and 3D rendering interface. Sparsely trained cycleGAN produced plausible virtual H&E staining from the unstained micro-CT reconstructions. Unlike tissue-section based histology, micro-CT-based virtual histology yields nondestructive 3D characterization of cancer cell and tissue architecture, including glandular spaces, without the undersampling or cutting artifacts of histology. These findings demonstrate the feasibility of PBCT-based 3D virtual histology of prostate cancer and suggest the exploration of derived quantitative analyses of tumor properties for potential contributions to patient care.

pathology↗