EMBO Molecular Medicine最新文献

Cardiac lymphatic alterations and insufficient lymphatic drainage have been found in cardiovascular diseases (CVDs). To unravel the mechanisms underlying lymphatic dysfunction, we applied single-cell (sc) analyses in murine heart failure (HF) models. Transaortic constriction (TAC) in C57BL/6J and BALB/c mice modeled chronic pressure -overload-induced cardiac hypertrophy and HF, respectively. Cardiac lymphatic (LEC) and blood vascular endothelial cells (BEC) were analyzed by scRNAseq, and targets validated by immunohistochemistry and human LEC cultures. While LEC profiles were comparable between strains in healthy mice, we found expansion of lymphatic capillaries and loss of valves post-TAC only in BALB/c. Differentially expressed gene (DEG) analysis revealed a reduction post-TAC only in BALB/c of lymphatic junctional components. Conversely, LEC expression of immune cell cross-talk mediators was mostly preserved post-TAC. Interestingly, around 35% of DEGs identified in cardiac LECs post-TAC were similarly altered in interleukin (IL)1β-stimulated human LECs. In conclusion, loss of lymphatic valves and dysregulated lymphatic barrier may underlie poor drainage capacity during pressure-overload-induced HF, despite potent lymphangiogenesis and preserved LEC immune attraction. Our work provides tractable targets to restore lymphatic health in CVDs.

Circulating blood proteomics enables minimally invasive biomarker discovery. Nanoparticle-based circulating plasma proteomics studies have reported varying number of proteins (ca 2000-7000), but it remains unclear whether a higher protein number is more informative. Here, we first develop OmniProt-a silica-nanoparticle workflow optimized through a systematic evaluation of nanoparticle types and protein corona formation parameters. Next, we present an Astral spectral library for 10,109 protein groups. Using the Astral with 60 sample-per-day throughput, OmniProt identifies ca 3000 to 6000 protein groups from human plasma. Platelet/erythrocyte/coagulation-related contamination artificially inflates protein identifications and compromises quantification accuracy in nanoparticle-enriched samples. Through controlled contamination experiments, we identified biomarkers for platelet/erythrocyte/coagulation-related contamination in nanoparticle-based plasma proteomics. We developed open-access software Baize for contamination assessment. We validated the pipeline in 193 patients with CT-indistinct benign nodules or early-stage lung cancers, flagging five contaminated samples. This study reveals that contamination alters protein identification/quantification in nanoparticle-based plasma proteomics and presents Baize software to evaluate it.

Salmonella Typhi secretes typhoid toxin that activates cellular DNA damage responses (DDR) during acute typhoid fever. Human infection challenge studies revealed that the toxin suppresses bacteraemia via unknown mechanisms. Using quantitative proteomic analysis on the plasma of bacteraemic participants, we demonstrate that wild-type toxigenic Salmonella induced secretion of lysozyme (LYZ) and apolipoprotein C3 (APOC3). Recombinant typhoid toxin or Salmonella infection recapitulated LYZ and APOC3 secretion in cultured cells, which involved ATM/ATR-dependent DDRs and confirmed observations in typhoid fever. LYZ caused spheroplast formation, inhibited the Salmonella type 3 secretion system, and intracellular infections. LYZ expression was regulated by p53 in a cell type-specific manner and driven by mitochondrial oxidative stress that caused nuclear DDRs and p53-mediated senescence responses. Addition of LYZ inhibited oxidative DNA damage and resulting senescence responses caused by typhoid toxin. Our findings may indicate that toxin-induced DDRs elicit antimicrobial responses, which suppress Salmonella bacteraemia during typhoid fever.

Primary human pancreatic ductal organoids (HPDO) have emerged as a model to study pancreas biology and model disease like pancreatitis and pancreatic cancer. Yet, donor material availability, genetic variability and a lack of extensive benchmarking to healthy and disease pancreas limits the range of applications. To address this gap, we established porcine pancreatic ductal organoids (PPDO) as a system from a reliable, genetically defined and easily obtainable source to model pancreatic ductal/progenitor biology. We benchmarked PPDO to HPDO and primary porcine pancreas using single-cell RNA sequencing (scRNA-Seq). We observed no overt phenotypic differences in PPDO derived from distinct developmental stages using extensive proteomics profiling, with a WNT/basal cell signaling enriched population characterizing PPDO. PPDO exhibited differentiation potential towards mature ductal cells and limited potential towards endocrine lineages. We used PPDO as a chemical screening platform to assess the safety of FDA-approved drugs and showed conserved toxicity of statins and α-adrenergic receptor inhibitors between PPDO and HPDO cultures. Overall, our results highlight the PPDO as a model for mammalian duct/progenitor applications.