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Babdor, J.

Publications and source records attributed to Babdor, J..

4 recordsLinked to original sources

A Reproducible Pre-Transplant γδ T-cell Effector Signature Reveals Immune-Metabolic Programs Associated with Kidney Allograft Rejection

Despite optimized immunosuppression, acute kidney transplant rejection affects 10-20% of recipients within the first year, and no reliable pre-transplant molecular test exists to identify patients at high risk, independent of the donor HLA matching. Across three independent cohorts of kidney transplant recipients, profiled by bulk RNA-sequencing with T-cell receptor repertoire analysis, flow cytometry, CyTOF with paired metabolomics, we identified a reproducible depletion of {gamma}{delta} T cells associated with rejection: an elevated {beta}/{gamma}{delta} T cell ratio in two post-transplant, biopsy-matched cohorts, and depletion of specific {gamma}{delta} T effector clusters in a third, longitudinally sampled cohort. In this third cohort, {gamma}{delta} T cell depletion was already present at the pre-transplant baseline in patients who subsequently developed rejection and remained detectable across the transplant course, indicating that it reflects recipient baseline immune biology rather than a consequence of graft injury. Longitudinal metabolomic profiling in this cohort identified time-dependent metabolic changes, including in amino acid metabolism that co-occur with the {gamma}{delta} signature and converge with it upon multi-omics integration. At the pre-transplant baseline, {gamma}{delta} T-cell marker expression alone showed exploratory discriminatory value for rejection risk (AUC = 0.69), improving marginally when integrated with metabolomic features (AUC = 0.71); larger prospective studies will be needed before clinical translation.

immunology↗

A widespread gut bacterial lineage distinguished by redox metabolism and phage defense

Genomic variation within gut microbial species can have consequences for host health and disease. However, for low abundance species, these variations can be difficult to capture by both culture-dependent and -independent approaches. Here, we focus on the prevalent but low abundance gut Actinomycetota Eggerthella lenta. We developed a selective media for sensitive and specific isolation of E. lenta from human stool. Genomes from 87 new E. lenta isolates were combined with prior high-quality assemblies, shedding light on within-species functional diversity. Phylogenetic analysis revealed a broadly distributed subclade, which we refer to as E. lenta Group B. This lineage was differentiated by its metabolic potential and bacteriophage defense, though mobile elements were shared broadly across the species. Notably, Group B was positively associated with intestinal inflammation in subjects with inflammatory bowel disease. Overall, these results emphasize the importance of bacterial population structure in host-microbiome interactions and provide a framework to study low-abundance gut taxa. HIGHLIGHTSO_LISelective media enables E. lenta isolation and reveals high prevalence in humans C_LIO_LIDiscovery of a distinctive lineage within E. lenta undergoing genome reduction C_LIO_LIE. lenta Group B has altered metabolism, phage defense, and disease associations C_LIO_LIA widespread conjugative plasmid could enable improved genetics C_LI

microbiology↗

Coordinated variation in the immune systems and microbiomes of healthy humans is linked to tonic interferon states

Human immune systems are highly variable, with most variation attributable to non-genetic sources. The gut microbiome crucially shapes the immune system; however, its relationship with the baseline immune states of healthy humans remains incompletely understood. Therefore, we performed multi-omic profiling of 110 healthy participants through the ImmunoMicrobiome study. A factor-based integrative approach identified coordinated variation, revealing that the tonic interferon response was amongst the most variable immune features in healthy participants. Microbiome composition, pathways, and stool metabolites varied concomitantly with interferon response pathways. Distinct transcriptional programs involving inflammation and TGF-{beta} in SIGLEC-1high monocytes and CD69high activated MAIT and NK cells were representative of these programs. Our study provides extensive data to examine the relationship between the immune states and microbiomes of healthy individuals at steady state, which paves the way for delineating inter-individual differences relevant for disease susceptibility and responses to therapy.

immunology↗

Comprehensive Immune Monitoring of Clinical Trials to Advance Human Immunotherapy

The success of immunotherapy has led to a myriad of new clinical trials. Connected to these trials are efforts to discover biomarkers providing mechanistic insight and predictive signatures for personalization. Still, the plethora of immune monitoring technologies can face investigator bias, missing unanticipated cellular responses in limited clinical material. We here present a mass cytometry workflow for standardized, systems-level biomarker discovery in immunotherapy trials. To broadly enumerate human immune cell identity and activity, we established and extensively assessed a reference panel of 33 antibodies to cover major cell subsets, simultaneously quantifying activation and immune checkpoint molecules in a single assay. The resulting assay enumerated [≥] 98% of peripheral immune cells with [≥] 4 positively identifying antigens. Robustness and reproducibility were demonstrated on multiple samples types, across research centers and by orthogonal measurements. Using automated analysis, we monitored complex immune dynamics, identifying signatures in bone-marrow transplantation associated graft-versus-host disease. This validated and available workflow ensures comprehensive immunophenotypic analysis, data comparability and will accelerate biomarker discovery in immunomodulatory therapeutics.

immunology↗