Clinical Journal of the American Society of Nephrology

Introduction Acute interstitial nephritis is an important differential diagnosis in patients with deteriorating kidney function. Diagnosis currently requires kidney biopsy, an invasive procedure associated with risks. We hypothesized that urinary T cells may serve as a non-invasive biomarker for acute interstitial nephritis. Methods A total of 320 patients undergoing clinically indicated kidney biopsy were enrolled in a discovery cohort at Charite Berlin (n = 80), an internal validation cohort at Charite (n = 100), and an external validation cohort at The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou (n = 140). Urinary immune cells were assessed by flow cytometry. Renal T cell infiltration was evaluated by immunofluorescence in kidney biopsy specimens from the discovery and internal validation cohorts, including 16 patients with acute interstitial nephritis and 9 patients without acute interstitial nephritis. Additionally, CXCL9 was measured by ELISA in 102 urine samples from these cohorts. Results Across all cohorts, 27 patients (8.4%) were diagnosed with acute interstitial nephritis. In the discovery cohort, multiple urinary T cell subsets were increased in acute interstitial nephritis, with activated CD4+ effector memory T cells expressing CD38 and HLA-DR showing the strongest diagnostic performance. This marker outperformed urinary monocytes, eosinophils, and CXCL9 and was validated in both independent cohorts. Across all cohorts, the area under the receiver operating characteristic curve was 0.84 and increased to 0.91 after exclusion of 8 patients receiving corticosteroids. A cutoff of 211 activated CD4+ effector memory T cells per 100 mL urine yielded a sensitivity of 78% and a specificity of 81%. Urinary activated CD4+ effector memory T cell counts correlated with renal CD4+ and CD4+ CD38+ T cell infiltration in acute interstitial nephritis. Conclusions Urinary activated CD4+ effector memory T cells expressing CD38 and HLA-DR represent a promising non-invasive biomarker for the diagnosis of acute interstitial nephritis.

Background: Early renal function decline is often accompanied by bothersome urological symptoms, yet effective early-stage nutritional interventions remain limited. L-Ergothioneine (EGT), a diet-derived antioxidant concentrated in renal tissue via the OCTN1 transporter, has shown renoprotective potential preclinically, but human interventional data are sparse. Methods: In this single-center, open-label, self-controlled trial, 31 adults (aged 45-70 years) with early renal function decline and persistent urological symptoms ([&ge;]3 months) received oral EGT (120 mg/day) for 90 days; 27 completed the study. Participants served as their own controls. The primary outcome was the within-subject change in eGFR (CKD-EPI 2021 creatinine); secondary outcomes included cystatin C-based eGFR, serum creatinine, UACR, a 10-item voiding diary, and a low-back-pain visual analogue scale (VAS). Within-subject changes were assessed by paired t-test or Wilcoxon signed-rank test. Results: Creatinine-based eGFR increased from 86.04 {+/-} 17.89 to 93.25 {+/-} 19.00 mL/min/1.73 m2 (+8.4%; p = 0.0016) and serum creatinine fell by 7.0% (p = 0.015). However, cystatin C-based eGFR and serum cystatin C were unchanged (p = 0.31 and p = 0.99), so the filtration signal was not corroborated by an independent, muscle-mass-independent marker. UACR showed a non-significant downward trend. Patient-reported outcomes improved most robustly: the total voiding diary score decreased by 57.2% (p < 0.0001) and low-back-pain VAS by 67.2% (p = 0.0002), with significant relief of urgency, frequency, and voiding difficulty. No product-related adverse events occurred. Conclusions: In this uncontrolled study, 90-day EGT supplementation was associated with marked improvement in urological symptoms and in creatinine-based eGFR, although the latter was not confirmed by cystatin C. These changes cannot be attributed to EGT alone and may substantially reflect placebo and natural-history effects. The findings are hypothesis-generating and warrant confirmation in a randomized, placebo-controlled trial using validated symptom instruments. Trial Registration: ChiCTR2500108897; Prospectively registered on 2025-09-08.

Background: Uremic pruritus affects up to 90% of individuals and substantially impairs quality of life, in the group of patients undergoing chronic dialysis. Despite multiple therapeutic options, an optimal and well tolerated treatment remains elusive. Ketotifen, a mast cell stabilizer with antihistaminic properties prevent itch by inhibition of mast cell derived tryptase, which modulates protease-activated receptor-2 (PAR-2) in the cowhage itch pathway. Materials and Methods: In this prospective observational study, 230 chronic dialysis patients were screened, of whom 48 (20.9%) had clinically significant pruritus identified using a structured questionnaire. Twenty-four patients with moderate-to-severe symptoms who were prescribed ketotifen as part of routine clinical care consented to prospective follow-up. Ketotifen was initiated at 1 mg twice daily, with dose escalation to 2 mg twice daily in patients with persistent symptoms according to routine clinical practice. Pruritus severity was assessed using visual (VAS), verbal (VRS), and numerical (NRS) rating scales before and after treatment. Results: After two weeks of initial 1mg therapy, 19 showed significant clinical improvement. Mean scores reduced 77.5 [-&gt;] 27.1 (VAS), 87.5 [-&gt;] 20.8 (VRS), and 74.2 [-&gt;] 25 (NRS) (around 65% reduction with p < 0.001 across all scales). Clinical relief was achieved in 83.3% overall and mild tolerable drowsiness occurred only at the 2mg dose. Conclusion: Ketotifen is a safe, effective and well tolerated option for moderate to severe uremic pruritus in dialysis patients. Larger multicenter studies are warranted to confirm efficacy and optimize dosing.

Rationale & Objective: People who live in rural areas with advanced chronic kidney disease (CKD) face well-documented structural barriers to receiving care, yet little is known about how they experience their illness or perceive interactions with their healthcare teams. We aimed to characterize the lived experiences and care perceptions of adults living in rural areas with advanced, pre-dialysis CKD. Study Design: We conducted semi-structured qualitative interviews with patients and care partners. Setting & Participants: We recruited patients with advanced CKD (stages 4-5, not on dialysis) and their care partners from a single hospital-based nephrology clinic in northern New England serving a predominantly rural population. Analytical Approach: We analyzed interview transcripts using participatory Practical Thematic Analysis (PTA), an inductive, stakeholder-engaged approach to qualitative analysis. Results: We interviewed 12 patients and 4 care partners. Four themes were identified: (1) logistical challenges of rural CKD care were pervasive but frequently normalized as an expected feature of rural life; (2) disease progression and future treatments were sources of uncertainty and concern, with expectations about dialysis often shaped by peer accounts rather than clinical discussion; (3) clinical conversations centered on laboratory results and medications, leaving emotional concerns and psychologic challenges unaddressed; and (4) physical symptoms and lifestyle changes were common but frequently attributed to comorbid conditions rather than to CKD. Limitations: Recruitment from a single clinic with a small, racially homogeneous sample limits transferability. While in-person recruitment may have excluded patients with greater transportation barriers, those who attended represent a population navigating substantial access challenges to receive care. Conclusions: Adults living in rural areas with advanced CKD experience logistical, emotional, and informational challenges broadly consistent with those reported in non-rural CKD populations. Patients normalized geographic barriers and did not consistently identify rurality as a source of disadvantage, even as structural barriers persisted. These findings support the development of structured communication approaches in nephrology care that invite discussion of disease trajectory, daily life impacts, and emotional concerns.

Background Diagnostic interpretation of kidney allograft biopsies using the Banff classification remains variable, but the determinants of this variability are not fully defined. We performed a global, fully digital multi-reader study to identify the principal drivers of disagreement in Banff-based assessment. Methods Thirty six kidney transplant biopsies were independently scored by 67 renal pathologists on a standardized digital platform. Readers assessed Banff lesions on hematoxylin and eosin, periodic acid Schiff, and Jones' silver stains; final diagnostic categories were assigned using prespecified Banff-based decision rules. Interobserver agreement was quantified with Gwet's agreement coefficient (AC) statistics. Determinants of diagnostic agreement were evaluated) using pairwise mixed-effects logistic regression, and reader similarity was examined by principal component analysis (PCA) with post hoc molecular annotation. Results Agreement for final diagnostic categories was moderate (Gwet's AC1, 0.55; 95% CI, 0.47 - 0.63). Lesion-level agreement varied substantially, with lowest agreement for selected threshold-dependent inflammatory or semi-quantitative lesions, including interstitial inflammation in areas of IFTA, peritubular capillaritis and arteriolar hyalinosis. Diagnostic concordance differed markedly across biopsies, indicating strong case-level heterogeneity. In pairwise models, differences in active inflammatory and vascular lesion scoring were the strongest correlates of diagnostic disagreement; reader experience and geography contributed minimally. Principal component analysis showed reader variation was organized along two dominant axes: a rejection-calling threshold axis linked mainly to tubulointerstitial inflammatory injury, and a T cell-mediated (TCMR/TI) and antibody-mediated/microvascular (AMR/MVI) inflammation-oriented phenotypic classification axis. Conclusion Interobserver variation in Banff-based kidney transplant biopsy assessment is structured rather than random and driven mainly by how readers threshold and integrate key inflammatory lesion compartments rather than experience or geographic location.

Background: Chronic kidney disease (CKD) is associated with alterations in the gut microbiome that promote the accumulation of gut-derived uremic solutes and contribute to systemic inflammation, vascular dysfunction, and disease progression. Dietary fiber has emerged as a promising modulator of gut microbial metabolism, yet the influence of fiber physicochemical properties, particularly fermentability and viscosity, on uremic metabolite production in CKD remains poorly understood. Objective: To systematically evaluate the effects of isolated dietary fiber interventions, classified by fermentability and viscosity, on gut microbial metabolites in CKD across experimental rodent models and randomized clinical trials, and to determine whether these fiber properties modify microbial metabolites. Methods: A systematic search of PubMed, Embase, CINAHL, and Cochrane Library (through June 2026) identified randomized controlled trials and controlled rodent studies assessing isolated dietary fiber in CKD. Eligible studies reported at least one gut-derived metabolite (i.e., indoxyl sulfate (IS), p-cresyl sulfate (PCS), trimethylamine-N-oxide (TMAO), tryptophan-derived indoles, or short-chain fatty acids (SCFAs)). Random-effects models were used for pooled estimates using weighted mean differences (WMD) for human studies and standardized mean differences (SMD) for animal studies. Subgroup analyses evaluated fiber fermentability, viscosity, intervention dose, duration, and CKD stage. Risk of bias was assessed with ROB-2 and SYRCLE, and evidence certainty with GRADE. Results: Twenty-eight studies (13 human, 15 animal) met eligibility criteria, comprising 511 participants and 312 animals with CKD. Isolated fiber supplementation, primarily fermentable and non-viscous fibers, reduced IS (human: -0.13 mg/dL; 95% CI: -0.25, -0.01; p = 0.03; animal: -1.99; 95% CI: -3.06, -0.92; p < 0.0001) and pCS (human: -0.23 mg/dL; 95% CI: -0.46, 0.001; p = 0.051; animal: -1.56; 95% CI: -2.08, -1.03; p < 0.0001). SCFAs increased in animal studies, including cecal acetate (2.00, 95% CI: 0.78 to 3.22; p = 0.001) and circulating propionate (1.51, 95% CI: 0.054 to 2.96; p=0.04). There were no dose-dependent effects, but longer interventions (>8 weeks) tended to lower pCS (-0.26 mg/dL, 95% CI: -0.55 to 0.02; p=0.06). Some heterogeneity and low-to-moderate certainty were observed. Conclusion: Isolated dietary fiber reduces major gut-derived uremic solutes in CKD, with fermentability influencing metabolic responsiveness, but with minimal studies on viscous fibers. Larger, longer-duration trials with standardized reporting of total fiber intake and clinical endpoints are needed to guide evidence-based dietary recommendations in CKD.

Background: Diabetic kidney disease (DKD) remains a leading cause of end-stage renal disease worldwide, characterized by progressive structural and metabolic alterations secondary to chronic hyperglycemia. While numerous type 1 and type 2 rodent models have been developed to study the pathophysiology of DKD, no single model perfectly recapitulates the full clinical spectrum of human disease. The selection of an optimal model depends deeply on the specific research objective, as phenotypic expression and histopathological severity vary significantly across different strains and induction methods. The present study provides a comparative analysis of the renal histological of three widely utilized murine models: the chemically induced streptozotocin (STZ) model and the genetic Akita (type 1) and db/db (type 2) models. Methods: Male STZ-induced (28 weeks post-induction), heterozygous Akita (28 weeks old), and db/db mice at two different age intervals (18-21 and 16-24 weeks old) were assessed. Renal injury was quantified using four light-microscopic parameters: glomerulomegaly, mesangial hypercellularity, tubular vacuolization and arteriolar hyalinosis. Due to observed discrepancies between metabolic and structural findings in the db/db strain, transmission electron microscopy (TEM) was employed for subcellular characterization. Results: All models exhibited significant hyperglycemia and albuminuria. At the light-microscopic level, STZ and Akita mice demonstrated consistent and pronounced renal lesions. In contrast, db/db mice despite increasing albuminuria and obesity, light microscopy revealed heterogeneous and inconsistent histopathological changes. However, TEM analysis of db/db mice kidneys successfully captured early ultrastructural injury, including irregular glomerular basement membrane (GBM) thickening and focal podocyte foot process effacement, which were undetectable by light microscopy. Conclusions: Our findings indicate that the Akita and STZ-induced models exhibit prominent structural alterations detectable by conventional light microscopy, whereas the db/db model requires ultrastructural evaluation by TEM to reliably confirm renal injury. This study underscores the limitation of routine histology in certain type 2 diabetes models and highlights the complementary value of TEM for accurate histopathological characterization. Collectively, the alternative histopathological markers identified herein offer sensitive and readily accessible indices for monitoring early-to-moderate DKD progression, providing a more robust framework for preclinical model selection and therapeutic evaluation in future studies.

The Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) is a crucial but labor-intensive tool for managing SLE. We developed a privacy-preserving, model-agnostic large language model (LLM) framework to automate SLEDAI-2K assessment from real-world electronic health records. The framework was developed on a specialist-verified ground truth of 658 clinical notes and externally validated on 56 MIMIC-IV discharge summaries. Seven open-source LLMs were evaluated using advanced prompting and ensemble strategies. The top-performing model, a two-layered GPT-OSS-120B + verifier, achieved a micro-F1 of 94.2% for descriptor classification and an 86% exact match for SLEDAI-2K scores on the internal set, with corresponding external validation performance of 87.7% and 64%, respectively. To demonstrate clinical utility, the LLMs were deployed on 2,576 serial notes from 108 SLE patients. Patients identified by the LLMs as achieving sustained low disease activity had a significantly lower incidence of stage 3 chronic kidney disease (log-rank p = 0.0053), the need for kidney replacement therapy (p = 0.044), and hospitalization (p = 0.021) over 18.3 years of follow-up. These findings demonstrate that privacy-preserving LLMs, when guided by a well-designed framework, can assist in specialist-level reasoning in autoimmune diseases, offering a scalable solution for clinical decision support and patient management.

Heterochromatin protein 1 (HP1 is an intrinsic component of heterochromatin domains where it is involved in a diverse set of functions including heterochromatin spreading and organization, chromatin compaction and transcriptional silencing. It has been suggested that HP1 functions through a phase separation mechanism, a process that has been observed in vitro in the presence of N-terminal phosphorylation, nucleic acids and nucleosome arrays. HP1 can also interact with numerous binding partners that contain a specific motif called an HP1 access code (HAC). HACs recognize and bind to an interface formed by the chromoshadow (CSD) domains in the HP1 homodimer, the functional form of the protein. It has been shown that some HP1 binding partners can enhance its phase separation ability while others disrupt the process. Here, we focus on the interactions between HP1 and three binding partners, namely the p150 subunit of the chromatin assembly factor 1 (CAF-1), the N-terminal domain of the lamin B receptor (LBR), and the mitotic protein Shugoshin 1 (Sgo1). Using phase separation assays, we show that CAF-1 prevents HP1 phase separation while LBR and Sgo1 enhance it. Binding assays, mutational studies, NMR spectroscopy and computational analysis allow us to dissect the contributions of the HAC motifs, the charge patterns of the binding partner sequences and the role of N-terminal phosphorylation on HP1 in condensate formation. Our results demonstrate that each binding partner uniquely balances these contributions to modulate the properties of HP1, while electrostatic interactions dominate the regulation of phosphorylated HP1. These results suggest that HP1 binding partners play an important role in the modulation of its properties and the regulation of its functions in distinct biological contexts.

Temporal niche partitioning is a strategy for reducing interspecies competition and strengthening reproductive isolation. It relies on animals confining their daily activity to distinct diurnal, crepuscular, or nocturnal windows. However, a hardwired temporal niche is only advantageous under stable, predictable ecological regimes; surviving dynamic environments demands behavioral flexibility. Yet, it remains unclear how animals override rigid biological constraints to rapidly exploit transiently available fitness-critical time windows. To address this, we leveraged the twilight-active, species-rich Drosophila genus and monitored their daily activity under naturalistic conditions. Here, we show that intense sociosexual interactions rapidly drive a species-specific reformatting of their canonical crepuscular niche. The dominant sensory modality used for sexual communication predicts niche shift direction: reliance on chemosensation for courtship redirects behavioral activity into the night, while visual reliance shifts it into the day. This temporal plasticity bypasses the circadian clock, instead operating via a conserved dopaminergic pathway. Dopamine operates a dual-output brain circuit that simultaneously inhibits sleep and sustains sexual motivation. Our results reveal how mating imperatives decouple behavioral timing from circadian command, enabling conditional colonization of otherwise restricted temporal windows. Ultimately, by driving the divergence of previously overlapping niches, sociosexually induced temporal plasticity provides a powerful mechanism for sympatric coexistence in crowded environments.

The spatial arrangement of immune cells in the tumor microenvironment (TME) varies widely, from dispersed to clustered and tumor excluded to infiltrating. Multiplexed spatial profiling is an effective means of characterizing tumor-infiltrating lymphocytes (TILs) and immune complexes such as tertiary lymphoid structures (TLS) in the TME. However, few approaches have been described for objectively parametrizing patterns of immune organization and assessing their association with biological or clinical variables. This makes it difficult to evaluate whether a set of tumors is relatively immunologically cold or hot. Here we describe an intuitive set of statistical tools (available in the R package, tlsR) for characterizing lymphocyte patterns in the TME of solid cancers. We apply tlsR to primary prostate cancer (PCa), which is often described as immunologically cold. Using a cohort of 29 radical prostatectomy specimens stratified into low Gleason-grade (LGG; n=15) and high Gleason-grades (HGG; n =14) we show that HGG PCa is significantly more infiltrated than LGG PCa with lymphocytes organized into B cell or T cell enriched immune clusters (BICs and TICs). A subset of these ICs have the B and T cell zonation and follicular dendritic cells characteristic of a bona fide TLS. HGGs are also enriched with ICs containing precursor exhausted T cells (Tpex) and proliferating B cells and their tumor compartments harbor granzyme-B+ cytotoxic T cells in contact with cancer cells. Thus, far from being cold, a subset of HGG PCa has features associated with active immune surveillance, a finding with implications for emerging PCa immunotherapies.

The incidence of early-onset colorectal cancer (CRC) has risen sharply in recent decades1, yet the biological basis underlying the distinct behavior of tumors arising in young versus aged tissues remains poorly understood. Here we show that aging reprograms the epigenetic landscape of the colon, restricting colon tumor growth through stable silencing of developmental and fetal gene programs. We find that colon tumors arising in aged mice are intrinsically less proliferative than those arising in young animals. Multi-omic profiling of normal colon and colon tumors reveals that aging drives DNA hypermethylation, loss of Polycomb-associated chromatin states, and reduced chromatin accessibility at a defined set of developmental genes that are bivalent (marked by both H3K27me3 and H3K4 methylation), transcriptionally active in colon tumors from young animals and repressed in both tumors and normal tissue from old animals. Among the genes most strongly repressed in old animals is Tacstd2 (Trop2), a regulator of fetal intestinal programs and epithelial stemness. Pharmacologic inhibition of DNA methylation reactivates the aging-silenced gene network in organoids from old animals, whereas genetic disruption of Tacstd2 suppresses growth and developmental transcriptional programs in young tumor organoids. TACSTD2, fetal gene signatures, and the aging-associated bivalent gene program are likewise repressed in late-onset vs. early-onset human colorectal cancers. Collectively, these findings identify age-associated epigenetic silencing of developmental gene programs as a causal mechanism that constrains colorectal tumor growth and provide a mechanistic framework for understanding the distinct biology of early-onset colorectal cancer.

Extrahepatic delivery of lipid nanoparticles (LNPs) to non-phagocytic cells is a major challenge, with the leading strategy involving surface functionalization with target-specific monoclonal antibody (mAb) ligands. We investigate the stability of mAb-conjugated LNPs using two anchoring systems: the commonly used DSPE-PEG2kDa-maleimide and a block copolymer, PCL5kDa-b-PEG2kDa -maleimide, with the hypothesis that conjugation to a 150,000 Da antibody could overwhelm the relatively small ~600 Da aliphatic anchor on the PEG-lipid in vivo. Shedding of the mAB would compromise targeting. Conjugation integrity following IV injection was assessed by tagging LNPs and mAbs with metal ion tracers that could be quantified by ICP-MS. Results show that DSPE-PEG-mAb rapidly (within 1h) dissociates from LNPs in blood, leading to accelerated LNP clearance. In contrast, mAbs conjugated using PCL-b-PEG remained stably associated with the LNP over the 24h circulation and clearance of the construct. Results are connected to a thermodynamic model that reproduces experimental findings for PEG-anchor(-mAb) shedding in vitro and in vivo. This study identifies anchoring strength as a critical, unconsidered parameter for in vivo performance when conjugating mAbs to LNPs for extrahepatic delivery.

Blockade by sedimentary particles, such as mineral crystals, is a continuous risk the kidney tubule faces. To prevent that, kidney resident macrophages form transepithelial protrusions and remove intratubular sedimentary particles, a behavior particularly prevailing in the medulla over the cortex. However, the molecular mechanisms underlying this characteristic behavior of medulla macrophages are incompletely understood. In this study, we identified that the medulla had higher mechanical stiffness than the cortex in steady state, which was further elevated when kidney stone formed. Increased tissue rigidity was sensed by medulla macrophages via mechanoreceptor Piezo1, which promoted macrophage protrusion formation and their ability to clean the tubules. Loss of Piezo1 expression in kidney macrophages predisposed mice to intratubular accumulation of mineral crystal in steady state and accelerated kidney stone formation during oxalate intake challenge. Signaling via Piezo1 mobilized molecules involved in cell adhesion and protrusion assembly, including Talin2 and focal adhesion kinase (FAK). Finally, we developed a first-of-its-kind cell-based therapy for the treatment of experimental nephrolithiasis by exploiting macrophage Piezo1 activity, and this strategy shows great promise for future translational research.

Whether different pathogens acquire resistance to antimicrobials through the same mutations is a major question in evolution and microbiology. Most antifungal drugs are used to treat infections caused by multiple fungal species, many of which have diverged for millions of years. If the evolution of resistance was to converge onto the same set of mutations across species, knowing the mechanism of resistance in one would allow us to predict and track it in others. The extent of this convergence remains unknown due to the lack of systematic data on resistance mutations. Here, we quantify the conservation of resistance mutations in the cytosine deaminase (CD), a protein responsible for resistance to flucytosine, one of the oldest antifungal drugs. By comparing the crystal structures of this enzyme through 600 My of evolution, we show that the CD structure is highly conserved. We compared the full CD mutational resistance spectrum of resistance from an ascomycete and a basidiomycete. We found that resistance mutations in one ortholog can be used to predict resistance in the other at a high level of accuracy. However, because of epistasis, around 10% of mutations have distinct effects in the two orthologs, which imposes an upper limit to the transferability of the knowledge of resistance mutations from one species to another. Using biochemical assays and by structural characterization of several mutants, we identify distinct mechanisms of epistasis, one important being that the local physiochemical environment of some position has evolved in a way that makes the same substitutions destabilizing or entirely inactivating in an ortholog-specific manner. Our results show that resistance mutations can be conserved in fungi across hundreds of millions of years of evolution but that epistasis eventually limits the accuracy of these predictions.

Single-nucleus transcriptomic atlases offer an unprecedented opportunity to connect cellular molecular states with Alzheimer's disease (AD) neuropathology, but whether these profiles encode reproducible, predictive information about pathological burden remains unclear. We present the SEA-AD DREAM Challenge, an open, international, model-to-data competition built on the Seattle Alzheimer's Disease Brain Cell Atlas to predict Alzheimer's disease neuropathological severity from single-nucleus RNA-sequencing data. Participants developed containerized models to predict categorical neuropathological staging, including overall Alzheimer's disease neuropathologic change, Braak stage, Thal phase, and CERAD score, as well as quantitative amyloid-{beta} and phospho-tau burden measured by 6E10 and AT8 immunohistochemistry. Across 17 eligible teams from 15 countries, the crowdsourcing framework enabled systematic comparison of diverse computational approaches and surfaced a broad landscape of modeling strategies and candidate predictive features. Top-performing methods achieved near-perfect prediction of categorical staging, with the best submission reaching a quadratic weighted kappa of 1.0 for the Overall AD Neuropathological Change score (ADNC), and competitive prediction of quantitative pathological burden in held-out data, with a best concordance correlation coefficient of 0.48. Post hoc perturbation analyses revealed that top categorical-stage predictions relied heavily on donor-level metadata-driven signals rather than transcriptomic features, whereas quantitative pathology prediction was more robust and supported by transcriptomic and cell-type-associated features with potential biological relevance to AD progression. The challenge also introduced the first AI Agent Track in a DREAM Challenge, providing an early benchmark for autonomous and human-guided agentic model development in single-cell neuroscience. This work demonstrates that single-nucleus transcriptomes encode substantial information about Alzheimer's disease pathology, establishes a reproducible benchmark for molecular neuropathology prediction, and highlights critical principles for designing privacy-preserving, leakage-aware community challenges using deeply phenotyped human brain data.

We showed before that the endogenous peptide Nociceptin blocks the premature differentiation of oligodendrocytes (OLGs), preventing untimely precocious myelination in the developing brain. Consistent with this early function, Nociceptin brain expression is developmentally regulated, sharply decreasing with the initiation and progression of myelination. However, we now found that at difference with controls and relapsing-remitting multiple sclerosis (RRMS), Nociceptin levels are highly elevated in cerebrospinal fluid from patients with the most severe progressive MS (PMS) forms. This questioned whether Nociceptin early developmental effects could be latter recapitulated, interfering with remyelination in PMS. This possibility was tested by inducing experimental autoimmune encephalomyelitis in older mice, at an age equivalent to that with increased risk of RRMS transition into PMS. Older animals develop persistently highly debilitating clinical symptoms, and display both brain and spinal cord demyelination. Importantly, these mice exhibit elevated brain Nociceptin levels, and their treatment with an antagonist of the Nociceptin receptor (NOR) elicits a regression of clinical scoring that is accompanied by higher ratios of OLGs/OLG progenitor cells, increased myelination, and reduction of reactive astrocytes. These findings suggest that Nociceptin may be a crucial player in the age-related progression of MS; interfering with OLG maturation and remyelination, and perhaps further exacerbating neurological dysfunction by targeting astrocyte populations. The upregulation of Nociceptin secretion by human astrocytes in response to proinflammatory cytokines, also points to this peptide as a mediator of microglia-astrocyte interactions supporting MS progression with aging. NOR may offer a novel pharmacological target for ameliorating the devastating effects of MS progression.

Brain areas differ in their inherent susceptibility to focal seizures, but the principles governing this risk remain unclear. While prior work has focused on anatomical and physiological factors, here we observed a fundamental contribution from the computations performed by the underlying neural network. Handcrafted and trained recurrent neural networks supporting continuous representations respond to seizure perturbations with higher activity and earlier performance decline relative to matched networks stabilizing discrete, well-separated states. Consistent with this prediction, in vivo recordings revealed that medial entorhinal cortex, whose grid cells exhibit continuous attractor dynamics, drives acute epileptiform discharges with stronger involvement and smoother state trajectories compared to CA3, a hippocampal subfield associated with discrete memory storage. Moreover, selective synaptic silencing demonstrated that this difference in seizure responses depends on intact entorhinal connectivity. Thus, the computations that enable neural networks to process information also influence their vulnerability to pathological transitions.

Joint music making offers an ecologically powerful framework for investigating human social interaction and synchronization. Yet, experimental paradigms often rely on traditional instruments that limit accessibility, reproducibility, and experimental control. In parallel, the use of music for therapy and rehabilitation is expanding, motivating the development of digital musical instruments that can serve research, educational, and clinical purposes. Here, we introduce the e-Music Box Roma (eMB Roma), an open, reproducible digital musical instrument designed to study music making behavior regardless of musical training. The eMB Roma plays preregistered music with tempo controlled by hand rotary movements. Building on the original e-Music Box (Novembre et al., 2015), the eMB Roma retains its intuitive rotary hand control while introducing major innovations: a fully open and 3D-printable design, modular hardware with integrated slider and button controls, polyphonic output with multiple simultaneous instruments, and MIDI compatibility. Additionally, a dedicated graphical user interface allows real-time monitoring, experiment control, device synchronization (like neuroimaging or motion capture devices), and both solo and joint music-making paradigms. The eMB Roma provides a flexible and accessible platform for research contexts, allowing experimental control, reproducibility, and future extensions. Its open design and modularity make it suitable not only for research but also for therapeutic, rehabilitation, and educational applications, where it can support personalized interventions and quantitative assessment of motor performance.

Representations of the same physical stimulus vary between individuals. Characterizing individual differences has practical implications, but is challenging because these representations are not directly observable. Given a model of how representations vary within a population, we propose a Bayesian adaptive procedure for estimating an individual observer's representation from a series of targeted perceptual discrimination judgments. A key component of our approach is using Fisher information to identify stimulus distortions that efficiently differentiate observers in the population. As a proof of concept, we focus on individual differences in color perception and simulate observers with cone fundamentals drawn from an individual colorimetric observer model. We demonstrate that our approach can recover key aspects of a sampled observer's cone fundamentals using simulated three-alternative forced-choice oddity judgments with approximately 500 trials, corresponding to an experimental duration of approximately one hour. Our Bayesian adaptive framework provides a promising and generalizable approach to efficiently link behavioral measurements to individual differences in sensory representations.