Science Translational Medicine

Medication-overuse headache (MOH) is one of the leading causes of chronic daily headache worldwide and arises from the repeated use of acute anti-migraine medications, including triptans. However, the cellular substrates and intracellular pathways driving this paradoxical chronification remain unknown. Here, using Schwann cell-selective silencing of the 5-HT1B/D receptor, we observed that acute triptan administration counteracts CGRP-induced, endosome-confined cAMP accumulation, preventing the development of periorbital mechanical allodynia in mice. In contrast, prolonged 5-HT1B/D activation in Schwann cells induces epigenetic and transcriptomic dysregulation associated with MOH in mice. Specifically, intronic hypermethylation-driven overexpression of BETAGLYCAN promotes activation of a non-canonical TGF-{beta}-dependent signaling cascade. The resulting TGF-{beta}3 upregulation establishes a feed-forward loop that sustains proalgesic paracrine communication between Schwann cells and primary sensory neurons. Analysis of plasma levels from patients with MOH confirmed elevated TGF-{beta}3 levels specifically associated with triptan-dependent MOH, supporting the translational relevance of these findings. Together, our data identify Schwann cell 5-HT1B/D signaling as a dual mediator of both the acute anti-migraine efficacy and the maladaptive mechanisms underlying MOH. These results provide a conceptual framework for strategies aimed at preserving the therapeutic benefits of triptans while limiting the adverse consequences of chronic administration. One Sentence SummarySchwann cell 5-HT1B/D receptor signaling mediates the dual effects of triptans by acutely inhibiting CGRP-driven nociceptive pathways while chronically promoting epigenetically driven TGF-{beta}3-dependent proalgesic signaling that causes medication-overuse headache.

Juvenile dermatomyositis (JDM) is a chronic multisystem vasculopathy and inflammatory myopathy characterized by proximal muscle weakness, distinct rash, and risk of complications such as calcinosis cutis, skin ulceration, and mortality. Molecular insight from diagnostic muscle biopsy histology is limited, and the mechanistic pathoetiology of JDM remains poorly defined. We used single nuclei transcriptomics to assess muscle samples from patients with newly diagnosed treatment-naive JDM. As a control, we assessed muscle samples from patients with congenital (nemaline) myopathy (CM), a non-inflammatory disorder. A total of 25,794 high quality nuclei were analyzed and clustered into various muscle-resident or infiltrating cellular populations. JDM tissue was characterized by an enriched interferon (IFN) response signature across endothelial, stromal, and immune cell compartments. Endothelial and perivascular populations showed increased inflammatory and angiogenic programs. Intercellular communication inference analysis identified dysregulated vascular endothelial growth factor (VEGF)-related signaling involving endothelial, stromal, and myonuclear populations as a possible mechanism for myonuclear-driven modulation of the muscle microvasculature. Spatial RNA in situ hybridization supported increased expression of selected IFN responsive and angiogenesis signaling genes in JDM tissue. Collectively, these data provide a cell type-resolved view of treatment-naive JDM muscle and highlight vascular and IFN pathways for follow-up in larger cohorts.

Clinicopathologic calculators for bladder cancer moderately predict survival and fail to depict the underlying molecular phenotype. We applied urinary capillary electrophoresis-mass spectrometry (CE-MS) to identify prognostic signatures linked to bladder cancer outcome. In a discovery cohort (n=131; mean follow-up 623 days), 114 survival-associated peptides, predominantly collagen fragments, were significant prognostic factors of survival and were integrated into a classifier (BC110), resulting in an accuracy of 0.80 (p-value < 0.001). Validation of the classifier in an independent cohort (n=102; mean follow-up 1605 days) confirmed correlation with survival (AUC: 0.78; p-value=0.03). Survival analysis using the BC110 scores resulted in significant prediction of both overall (p-value<0.0001) and progression-free survival outcome (p-value < 0.0001). To test biological plausibility, a previously reported collagen-focused model (COL210) was subsequently investigated and demonstrated concordant prognostic separation, reinforcing extracellular matrix remodeling as the underlying signal. These urine-based classifiers enable non-invasive risk stratification and may complement guideline calculators by identifying high-risk patients for adjuvant therapy and low-risk groups for reduced surveillance, potentially lowering reliance on repeated cystoscopy. Significance StatementAccurate non-invasive risk stratification in bladder cancer remains a major unmet clinical need, given the diseases high recurrence rates and the need for cystoscopic surveillance. We applied a standardized urinary peptidomics workflow using capillary electrophoresis-mass spectrometry (CE-MS) to develop a machine learning based classifier (BC110) enriched in collagen and other extracellular matrix (ECM) components, in a discovery cohort (n=131) of mainly NMIBC patients. In an independent validation cohort (n=102), BC110 achieved robust quartile-based separation of overall and progression-free survival, with a PFS hazard ratio of 7.23 (highest vs. lowest quartile; p<0.0001). Prognostic performance was further confirmed with a previously reported fibrillar collagen model (COL210), identifying ECM remodeling as the biological driver of the peptide alterations depicted in urine in association with BC progression. These classifiers provide a reproducible, urine-based approach to non-invasive survival prediction, enabling risk-adapted surveillance and earlier therapeutic intervention. While urinary peptidomics requires prospective validation, it is poised to reduce reliance on invasive cystoscopy and to advance personalized care through clinical implementation.

Sepsis is a leading cause of morbidity and mortality in critically ill children, yet heterogeneity in immune responses complicates the development of targeted therapies. Although immune dysregulation is associated with poor outcomes in sepsis, it remains unclear which host immune factors contribute causally to sepsis morbidity and mortality. To address this gap, we integrated deep immune phenotyping, plasma proteomics, single-cell transcriptomics, and phosphoflow cytometry in a prospective cohort of 88 critically ill children to elucidate the immunologic mechanisms which underly disease heterogeneity. Unsupervised clustering of plasma cytokines identified three immunologic subgroups, including a high-severity group ("Group C") characterized by marked hypercytokinemia, driven primarily by IL-6 and IFN-{gamma}. Group C exhibited distinct alterations in immune cell frequency and activation status, along with a strong association between hyperinflammatory signaling and lymphocyte dysfunction. Single-cell RNA sequencing revealed transcriptional signatures of T cell activation and metabolic stress, and identified widespread suppression of a lymphoid protective gene program across CD8 T cell subsets. In the setting of increased expression of activation markers, T cell receptor repertoire analysis revealed no dominant clonotypes, consistent with a bystander mechanism of T cell activation. Using phosphoflow cytometry, we demonstrated baseline hyperactivation of STAT1 and STAT3 in CD8 T cells from patients in Group C, and these cells failed to respond to aCD3/aCD28 stimulation. Together, these findings define IL-6/IFN-{gamma}-driven T-cell dysfunction as a distinct endotype of immune dysregulation in pediatric sepsis, highlighting the JAK/STAT axis as a potential future target for immunomodulatory therapy.

Recurrent urinary tract infections (rUTIs) are a major health burden worldwide, with history of infection being a significant risk factor. While the gut is a known reservoir for uropathogenic bacteria, the role of the microbiota in rUTI remains unclear. We conducted a year-long study of women with and without history of rUTIs, from whom we collected urine, blood and monthly fecal samples for multi-omic interrogation. The rUTI gut microbiome was significantly depleted in microbial richness and butyrate-producing bacteria compared to controls, reminiscent of other inflammatory conditions, though Escherichia coli gut and bladder dynamics were comparable between cohorts. Blood samples revealed signals of differential systemic immunity, leading us to hypothesize that rUTI susceptibility is in part mediated through a syndrome involving the gut-bladder axis, comprising gut dysbiosis and differential immune response to bacterial bladder colonization, manifesting in symptoms. This work highlights the potential for microbiome therapeutics to prevent and treat rUTIs.

ObjectiveTo determine whether quantitative ultrasound (QUS), which characterizes tissue microstructure using radiofrequency data, can identify regional heterogeneity within seminiferous tubules that corresponds to localized spermatogenesis in men with non-obstructive azoospermia (NOA). DesignTwo-cohort study using a biological extremes cohort to establish plausibility of a QUS biomarker, followed by an independent NOA-biopsy cohort with site-matched imaging and tissue sampling. SettingAcademic male fertility referral center. PatientsThe biological extremes cohort included fertile men with presumed intact spermatogenesis (n=15) and men with NOA and subsequent negative microdissection testicular sperm extraction (mTESE; n=10). The NOA-biopsy cohort consisted of 27 men with NOA undergoing site-matched testicular biopsy via testicular sperm aspiration (TESA) or testicular sperm extraction (TESE), yielding 12 sperm-positive and 36 sperm-negative biopsy sites. InterventionsHigh-frequency testicular ultrasound (36 MHz) with acquisition of raw radiofrequency data, allowing objective, quantitative analysis of tissue scattering patterns beyond conventional grayscale imaging. Regions of interest were manually annotated and, in the NOA-biopsy cohort, spatially matched to biopsy locations. Main Outcome MeasuresAssociation between sperm presence at biopsy sites and a pre-specified QUS measure of local tissue heterogeneity: the 75th percentile of a sliding window coefficient of variation map of the Nakagami k-factor within the superficial testicular parenchyma (K_Zone1_CV). This metric reflects the upper range of local variability in ultrasound backscatter, which is influenced by the underlying organization of seminiferous tubules. ResultsIn the biological extremes cohort, K_Zone1_CV distinguished fertile controls (median 1.79, IQR 1.64-1.85) from NOA men with globally negative mTESE (median 1.51, IQR 1.42-1.58; P < 0.001), with an area under the receiver operating characteristic curve (AUC) of 0.91 (95% CI 0.79-1.00). In the independent NOA-biopsy cohort, K_Zone1_CV discriminated sperm-positive from sperm-negative biopsy sites with an AUC of 0.93 (95% CI 0.85-0.99). At a threshold of 1.60, sensitivity was 100%, specificity was 86.1%, positive predictive value was 70.6%, and negative predictive value was 100%. Serum hormone levels, testicular volumes, and biopsy technique did not differ significantly between groups. ConclusionsRegional testicular tissue heterogeneity measured by quantitative ultrasound is associated with localized spermatogenesis in men with NOA. At the selected threshold, no sperm-positive biopsy site was misclassified as negative. These findings support the hypothesis that QUS can noninvasively detect the focal seminiferous tubule heterogeneity that predicts sperm retrieval success. This imaging approach could inform future image-guided sperm retrieval strategies. Further validation in larger cohorts and assessment of intra-patient variability are needed.

Histopathological evaluation of skeletal muscle biopsies relies on subjective, semi-quantitative assessment with no standardized grading system. We developed a four-tissue deep learning segmentation pipeline using Cellpose-SAM for myofiber instance segmentation, a pixel classifier for fat infiltration, and watershed detection for nuclei. We applied this pipeline to 478 H&E whole-slide images from two independent cohorts: HuashanMuscle (n = 79; China; myotonic dystrophy type 1 [DM1], n = 28; limb-girdle muscular dystrophy type R1 [LGMDR1, calpainopathy], n = 12; type R2 [LGMDR2, dysferlinopathy], n = 22; controls, n = 17) and GTEx (n = 399; United States; three-level myopathy spectrum). Thirty-seven unique morphometric features were extracted per sample. Nuclear centralization index (NCI) and fiber size variability coefficient (fiber CV) discriminated myopathy from controls (p = 1.3E-05, rank-biserial r = 0.69; and p = 2.9E-04, r = 0.58, respectively). DM1 showed the highest NCI (median 0.121), consistent with its centronuclear pathology, and NCI correlated with CTG repeat count (Spearman rho = 0.46, p = 0.042, n = 20). In the GTEx cohort, both biomarkers exhibited significant dose-response trends across the myopathy spectrum (Jonckheere-Terpstra p < E-04). The MyoPath Score, a logistic regression composite of seven pathology indicators trained on GTEx, achieved AUC = 0.788 (LOO-CV 0.735) and transferred to the independent HuashanMuscle cohort with AUC = 0.873 without retraining. Segmentation achieved Dice coefficients of 0.92 (myofiber), 0.95 (fat), 0.87 (nucleus), and 0.88 (connective tissue), with intraclass correlation coefficients exceeding 0.88. NCI and fiber CV provide objective, reproducible quantitative biomarkers for skeletal muscle pathology severity assessment with potential as standardized grading criteria and clinical trial endpoints.

BackgroundAzoospermia, characterized by the absence of sperm in the ejaculate, impacts 1% of men globally. Surgical approaches to retrieve sperm from the testis are effective in some cases but can be invasive and expensive. Here we described a noninvasive ultrasound-guided rete testis (UGRT) approach to retrieve sperm from the testes or infuse stem cells into the testes of men with azoospermia. MethodsUltrasound was used to guide insertion of a 25-gauge hypodermic needle through the base of the scrotum and into the rete testis space that is contiguous with all seminiferous tubules. Medium was infused into the rete testis and aspirated to retrieve sperm from monkeys and men (NCT03291522) with azoospermia. A peripubertal patient with osteosarcoma of the femur cryopreserved a testicular cell suspension to safeguard his future fertility (NCT02972801). He returned as a young adult (21-25 yo) survivor for autologous transplantation of his cryopreserved testicular cells, including spermatogonial stem cells, using the UGRT approach (NCT04452305). FindingsSperm were successfully aspirated from four of six monkeys with radiation-induced azoospermia and three of three patients with obstructive azoospermia, demonstrating proficiency with the UGRT approach. Sperm were not recovered from the testes of seven patients with nonobstructive azoospermia. Semen analysis confirmed that the adult survivor of childhood cancer was azoospermic. His cryopreserved testis cells were transplanted back into one testis, with no adverse effects. After transplantation, the testicular parenchyma had a normal homogeneous appearance. Testosterone, Follicle Stimulating Hormone, and Luteinizing Hormone levels were normal. Inhibin B levels were low. The patient remains azoospermic one year after transplantation. InterpretationWe describe a platform for proficiency training in UGRT flushing, aspiration, or injection. This provides a noninvasive option for sperm retrieval and infusing stem cells or other therapeutics into the testis. FundingThe Eunice Kennedy Shriver National Institute for Child Health and Human Development HD100197 and the UPMC Magee Center for Reproduction and Transplantation.

Patients with rheumatoid arthritis (RA) display distinct patterns of synovitis. To define the inflammatory mechanisms driving this heterogeneity, we analyzed the inflamed synovium of wild-type (WT), Il6ra-/-, and Il27ra-/- mice with antigen-induced arthritis (AIA). Remarkably, each strain developed a joint pathology mirroring a major RA synovial pathotype: myeloid-rich (WT), fibroblast-rich/pauci-immune (Il6ra-/-), and lymphoid-rich (Il27ra-/-) synovitis. Histology confirmed minimal immune infiltration in Il6ra-/- joints, while WT and Il27ra-/- mice exhibited prominent immune involvement, including organized synovial lymphoid-like aggregates in Il27ra-/- mice. Transcriptomic and epigenomic profiling revealed both shared and distinct regulatory programs among genotypes. Il6ra-/- mice showed increased WNT, DKK, and AMPK signaling associated with fibroblast, chondrocyte, and osteoclast activation (e.g., Adamts19, Dkk1, Ecm1). Consistent with synovial ectopic lymphoid-like structures, Il27ra-/- mice showed enrichment of lymphocyte activation (e.g., Il17a, Il22, Bhlhe40). WT mice exhibited hallmarks of MAP kinase activation. These molecular signatures parallel those of fibroblast-, lymphoid-, and myeloid-rich synovitis in RA. Defining a STAT1-STAT3 regulatory interplay influencing transcriptional decisions in WT and Il27ra-/- mice, our findings offer insights into cytokine-driven disease heterogeneity. Together, these results establish a framework for mechanism-based classification of synovitis and introduce new mouse models to study the molecular drivers of synovial pathotypes and treatment response.

Sepsis, the dysregulated host response to infection causing life-threatening organ dysfunction, is an unmet global health challenge. Here we apply high-throughput tandem mass spectrometry to delineate the plasma proteome for sepsis and comparator groups (non-infected critical illness, post-operative inflammation and healthy volunteers) involving 2622 samples and 4553 liquid chromatography-mass spectrometry analyses in a single batch, at 100 samples/day. We show how this scale of data can establish shared and specific proteins, pathways and co-expression modules in sepsis, and be integrated with paired leukocyte transcriptomic data (n=837 samples) using matrix decomposition. We map the landscape of the host response in sepsis including changes over time, and identify features relating to etiology, clinical phenotypes and severity. This work reveals novel subphenotypes informative for sepsis response state, disease processes and outcome, highlights potential biomarkers, pathways and processes for drug targets, and advances a systems-based precision medicine approach to sepsis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with no definitive disease-modifying therapies available, underscoring the urgent need to identify novel druggable targets. The G protein-coupled receptor GPR17 is a critical regulator of oligodendrocyte maturation and has emerged as a candidate target in ALS, yet its relevance to human disease and therapeutic potential remain unclear. Here, we demonstrate that pathological GPR17 upregulation defines a conserved, pathologically immature oligodendroglial state in human ALS that can be pharmacologically leveraged to restore myelin integrity and improve functional outcome in vivo. Publicly available transcriptomics datasets and histological analysis revealed an increased abundance of GPR17-expressing immature oligodendrocytes in post-mortem human spinal cord tissue from ALS cases compared with non-neurological controls. Moreover, sustained activation of GPR17 with a selective agonist was able to induce GPR17 internalization in heterologous expression systems. In line with this mechanism, treatment with the same agonist promoted the differentiation of primary oligodendrocyte precursor cells derived from SOD1G93A mice. Translating these findings in vivo, chronic treatment with a brain-penetrant GPR17 agonist derived from the same pharmacological class significantly extended survival, delayed body weight loss, and improved motor performance in female SOD1G93A mice, whereas male mice showed no therapeutic benefit. These effects were associated with restored oligodendrocyte maturation, preserved myelin integrity, motor neuron survival, and attenuated reactive gliosis in the spinal cord of female SOD1G93A mice, while milder effects were observed in males. Together, these findings establish oligodendroglial GPR17 as a conserved and pharmacologically actionable target in ALS and show that sustained in vivo GPR17 agonism can reprogram altered oligodendroglial states and slow disease progression in a sex-dependent manner.

Pediatric Inflammatory Bowel Disease (IBD) remains challenging to treat and difficult to prognosticate. Although multiple immune cell types coordinate pathology in both Crohns disease (CD) and ulcerative colitis (UC), specifying which cell types and cell states portend better or worse response to major IBD treatment strategies, including anti-TNF therapies (the only FDA-approved therapy for pediatric IBD), remains challenging. Here, we present the results of the PREDICT study, which enrolled 79 treatment-naive pediatric patients at the time of diagnostic endoscopy, enabling a comprehensive transcriptomic, histologic, and serologic analysis of 40 CD patients and 16 UC patients, as well as 23 patients with functional gastrointestinal disorders (FGID) who served as pediatric non-inflamed controls. Leveraging these data, we performed a comprehensive analysis of colonic immunology in each of these clinical conditions. Our results indicate that, within the complex landscape of immune pathology in pediatric CD and UC, there is a coordinated shift across the TH1-to-TH17 immune activation continuum among T cells that is pertinent to anti-TNF response. For CD, this shift defines partial response to anti-TNF treatment. For UC, the landscape is more complex, with both TH17 and TFH biology defining disease, and pre-treatment TH17 biology contributing to anti-TNF treatment resistance. Related to this, polyreactive TCR phenotypes within UC TFH cells are correlated with both germinal center activity and the frequency of IgG1 plasma cells, yet opposed to the TH17 signatures associated with anti-TNF nonresponse. The elucidation of these distinct mechanisms of T cell-dependent disease pathology, treatment response, and TCR polyreactivity suggests a model in which sustained TH17 signaling in CD and baseline TH17 signaling in UC are associated with disease pathogenesis, forming a basis for a generalized understanding of IBD pathogenesis and underscoring the need for endotype-specific approaches to IBD therapy.

Despite the success of antiretroviral therapy (ART) in suppressing HIV-1 replication, viral reservoirs persist and reignite viremia upon treatment interruption, posing a major barrier to achieving a cure. Analytical treatment interruption (ATI) is a key experimental strategy in HIV-1 cure research, used to evaluate the efficacy of novel therapeutic interventions. While ATI protocols have evolved to minimize clinical risks, the long-term consequences of ATI remain poorly understood. Here, we investigated the enduring immunologic and virologic effects of extended ATI in a unique cohort of volunteers enrolled in a dendritic cell-based therapeutic vaccine trial (DC-TRN) nearly two decades ago. Participants were re-evaluated more than 10 years after ART resumption. Using integrated approaches--including proviral reservoir quantification, inducibility profiling and high-dimensional immune phenotyping--we identified a significant expansion of the inducible HIV-1 reservoir and a distinct immune signature, despite sustained viral suppression and clinical stability. Notably, Central Memory T cells expressing CXCR3 positively correlated with inducible tat/rev msRNA+ T cells. These findings underscore the durable imprint of ATI-based immune interventions on HIV-1 reservoir dynamics and immune homeostasis. Overall, the findings emphasize the need for extended follow-up and functional immune assessments in HIV-1 cure-focused trials.

Sepsis is a dysregulated host response to infection and a leading cause of global mortality, yet effective targeted therapies remain lacking. Here, we applied a proteogenomic framework integrating large-scale human genetics with circulating proteomics to identify therapeutic targets. In a meta-analysis of genome-wide association studies of 60,314 sepsis cases and 1,464,733 controls, we identified four genome-wide significant loci, including a missense variant in SERPINA1, encoding alpha-1 antitrypsin (AAT), that was also associated with 30-day sepsis mortality in the UK Biobank. Mendelian randomization (MR) and colocalization analyses supported a causal and protective effect of higher genetically predicted circulating AAT levels on sepsis risk. The protective association was highly specific to acute infectious phenotypes, including pneumonia, and was not observed for non-infectious traits. In two independent cohorts (UK Genomic Advances in Sepsis and the Biobanque Quebecois sur la COVID-19), circulating AAT increased markedly during acute illness but was significantly attenuated among missense variant carriers in a dose-dependent manner, consistent with impaired protease-antiprotease balance. MR of the AAT-regulated proteome recapitulated findings from prior sepsis trials, both negative and positive, providing orthogonal genetic support for therapeutic modulation of this pathway. Together, these findings provide the first human genetic evidence for AAT's causal role in sepsis, positioning SERPINA1 as a high-priority candidate for drug repurposing and targeted therapeutic interventions.

Interleukin-10 (IL-10) is a potent immunoregulatory cytokine that suppresses pro-inflammatory cytokine production, reduces antigen presentation by myeloid cells, promotes M2 macrophage polarization, and inhibits T cell activation. Despite these well-established immunoregulatory functions, efforts to harness recombinant IL-10 therapeutically have been limited by its short plasma half-life and poor retention in the secondary lymphoid organs (SLOs), key sites of autoreactive T cell priming in autoimmune disease. Previously, we engineered a fusion of serum albumin and IL-10 (SA-IL-10) with extended half-life and enhanced exposure in the SLOs following intravenous administration. Here, we integrate human transcriptomic analyses and a murine model of neuroinflammation, experimental autoimmune encephalomyelitis (EAE), to investigate how sustained IL-10 exposure in the SLOs modulates immune responses under inflammatory conditions. Human single-cell RNA sequencing analyses revealed reduced IL-10 expression alongside increased IL-10 receptor expression across multiple immune cell populations in treatment-naive patients with multiple sclerosis (MS), motivating the investigation of IL-10-based immunomodulatory strategies. Prophylactic SA-IL-10 administration prevented the development and progression of EAE with superior efficacy to wild type IL-10 and comparable protection to fingolimod, an FDA-approved MS therapy. Immunophenotyping of the SLOs revealed that SA-IL-10 suppressed pathogenic, antigen-specific ROR{gamma}t+ Foxp3- TH17 T cells, CD86+ M1-like macrophages, CD86+ dendritic cells, and pro-inflammatory cytokine production, while expanding immunoregulatory CD206+ M2-like macrophages and increasing the frequency of multiple checkpoint markers (CTLA-4, PD-1, TIGIT, ICOS) on GATA3+ Foxp3- TH2 cells. Despite the absence of direct central nervous system targeting, SA-IL-10 treatment also reduced the infiltration of macrophages, dendritic cells, and CD4+ T cells into the spinal cord. Repeated SA-IL-10 administration was well tolerated, as treated EAE mice gained significantly more body weight over the course of treatment compared to PBS- and WT IL-10-treated controls, and exhibited plasma biochemistry parameters comparable to control animals at study endpoint. Together, these findings demonstrate that increasing IL-10 exposure in the SLOs suppresses neuroinflammation by promoting immunoregulation. One Sentence SummarySubcutaneously administered serum albumin-fused interleukin-10 prevents experimental autoimmune encephalomyelitis by suppressing pathogenic TH17 cells and pro-inflammatory myeloid cells in the secondary lymphoid organs and spinal cord, while expanding immunoregulatory cells in the secondary lymphoid organs.

Broadly neutralizing antibodies (bnAbs) that target the HIV gp41 membrane-proximal external region (MPER) have some of the highest neutralization breadth. An MPER peptide-liposome vaccine has been found to expand MPER bnAb precursors in monkeys. The HVTN133 phase 1 clinical trial (NCT03934541) studied the MPER peptide-liposome immunogen in 24 HIV-1 seronegative individuals. Participants were randomized in a dose-escalation design to either 500 mcg or 2000 mcg of the MPER-peptide liposome or placebo. Four intramuscular injections were planned at months 0, 2, 6, and 12. The trial was stopped prematurely due to an anaphylaxis reaction in one participant attributed to vaccine-associated polyethylene glycol. The immunogen induced MPER-specific serum antibodies and CD4+ T-cell responses in 95% and 85% of vaccinees, respectively, and 35% of vaccine recipients had circulating IgG+ memory B cells with an MPER-bnAb binding phenotype. Affinity purification of plasma MPER-specific IgG demonstrated tier 2 HIV-1 neutralizing activity in two of five participants after 3 immunizations and tier 2 HIV-1 neutralizing B cell clonal lineages were isolated from MPER-reactive B cells. These results demonstrate that the HIV gp41 MPER region is a promising target for induction of heterologous neutralizing antibodies by a candidate HIV vaccine. Trial Registrationhttp://www.clinicaltrials.gov/ Identifier: NCT03934541 FundingNational Institutes of Health, Bill and Melinda Gates Foundation

The heterogeneity of brain aging is a hallmark of neurological and psychiatric disorders, yet machine-learning tools used to characterize this process, including the brain age paradigm, have largely relied on global metrics that lack the specificity to map these complex patterns. Here, we introduce BrainAgeMap, an interpretable deep learning framework that generates fine-grained, voxel-wise maps of brain-predicted age difference (brain-PAD) from T1-weighted magnetic resonance imaging scans. We provide converging lines of evidence for the frameworks clinical, prognostic, and neurobiological utility. Disorder-specific topographies of accelerated aging were identified in Alzheimers disease (AD), frontotemporal dementia, and schizophrenia. Longitudinal analysis of the hippocampus revealed accelerated aging in individuals with progressive versus stable mild cognitive impairment (MCI), demonstrating prognostic value. Regional brain-PAD in the temporal lobe correlated strongly with in vivo tau pathology measured by positron emission tomography in AD, linking the maps to underlying molecular pathology. Furthermore, regional brain aging in MCI and AD was linked to individual differences in episodic memory function. BrainAgeMap provides a robust tool to delineate disease-specific pathways of neurodegeneration, offering new opportunities for early diagnosis, patient stratification, and monitoring therapeutic interventions.

Breakthrough infections of patients on antimicrobial prophylaxis represent a significant and often unexplained cause of morbidity. Here, we reveal that in high-risk patients on micafungin prophylaxis heteroresistance - the presence of a phenotypically unstable, low frequency subpopulation of resistant cells ([~]1 in 10,000) - underlies breakthrough bloodstream infections by Candida parapsilosis misclassified as susceptible by standard antimicrobial susceptibility testing. By analyzing 219 clinical C. parapsilosis isolates from North America, Europe, and Asia, we demonstrate widespread micafungin heteroresistance. To facilitate detection of micafungin heteroresistance, we constructed a predictive machine learning framework that classifies isolates as heteroresistant or susceptible by a maximum of ten genomic features. Our results connect heteroresistance to unexplained prophylaxis failure and demonstrate a proof-of-principle diagnostic approach with the potential to inform clinical decisions.

Management of peripheral nervous system (PNS) neuropathies, such as traumatic peripheral nerve injury (PNI), relies on accurate assessment of muscle denervation and recovery. Yet, the current gold-standard clinical test, needle electromyography (EMG), has multiple shortcomings that can complicate surgical treatment. Here, we introduce a noninvasive method for holistic evaluation of muscle denervation by utilizing positron emission tomography (PET) to quantify expression of prostate-specific membrane antigen (PSMA), also known as glutamate carboxypeptidase II (GCPII), within muscles. We identified that GCPII is persistently over-expressed in denervated muscles and that expression normalizes with muscle reinnervation. Leveraging this phenomenon, we used two PSMA/GCPII-PET agents that are FDA-approved for prostate cancer imaging, [18F]DCFPyL and [68Ga]PSMA-11, to detect muscle denervation and subsequent reinnervation in experimental models of PNI. We found that denervated muscle had approximately twice the uptake as innervated muscle on GCPII-PET/magnetic resonance (MR) imaging and GCPII-PET/computed tomography (CT), which persisted for at least 16 weeks after nerve injury without repair in rats and swine. GCPII-targeted uptake also declined to near baseline levels with muscle reinnervation after nerve repair. To assess clinical feasibility, we performed [18F]DCFPyL PET/CT in a patient who had sustained a unilateral radial nerve injury 15 weeks prior, and we observed elevations in denervated muscle uptake that mirrored our preclinical findings. Our consistent findings across species of increased GCPII-PET uptake in chronically denervated muscle and its decline with muscle reinnervation, along with the established safety profile of available GCPII-PET agents, support the promise of GCPII-PET as a rapidly translatable strategy for characterization and longitudinal monitoring of PNIs and non-traumatic PNS neuropathies.

Eating a varied diet is a central tenet of good nutrition. Here, we develop the first molecular tool to quantify human dietary plant diversity by applying DNA metabarcoding with the chloroplast trnL-P6 marker to 1,001 fecal samples from 310 participants across four cohorts. The number of plant taxa per sample (plant metabarcoding richness, or pMR) correlated with recorded intakes in interventional diets ({rho}=0.31) and with indices calculated from a food-frequency questionnaire in freely-chosen diets ({rho}=0.40-0.63). In adolescents unable to collect validated dietary survey data, trnL metabarcoding detected 111 plant taxa, with 86 consumed by more than one individual and four (wheat, chocolate, corn, and potato family) consumed by >70% of individuals. Adolescent pMR was associated with age and income, replicating prior epidemiologic findings. Overall, trnL metabarcoding promises an objective and accurate measure of the number and types of plants consumed that is applicable to diverse human populations.