AUTHOR=Cui Jing , Oehrl Stephanie , Ahmad Fareed , Brenner Thorsten , Uhle Florian , Nusshag Christian , Rupp Christoph , Funck Felix , Meisel Stefan , Weigand Markus A. , Morath Christian , Schäkel Knut TITLE=Detection of In Vivo Inflammasome Activation for Predicting Sepsis Mortality JOURNAL=Frontiers in Immunology VOLUME=11 YEAR=2021 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2020.613745 DOI=10.3389/fimmu.2020.613745 ISSN=1664-3224 ABSTRACT=

Sepsis is a severe life-threatening syndrome caused by dysregulated host responses to infection. Biomarkers that allow for monitoring the patient’s immune status are needed. Recently, a flow cytometry-based detection of in vivo inflammasome activation by formation of cytoplasmic aggregates of ASC (apoptosis-associated speck-like protein containing a caspase recruitment domain) has been proposed. Here we report on the frequency of ASC-speck+ leukocytes correlating with the survival of sepsis. 25 patients with sepsis were sampled consecutively for 7 days. Blood, serum samples and patient data were collected according to the guidelines of the PredARRT-Sep-Trial. Flow cytometric analysis was performed on fresh whole blood samples to investigate the formation of ASC-specks in leukocyte subsets. Serum samples were analyzed for production of IL-1ß, IL-18 and additional inflammatory markers. ASC-speck formation was found to be increased in leukocytes from sepsis patients compared to healthy donor controls. The absolute number of ASC-speck+ neutrophils peaked on day 1. For monocytes, the highest percentage and maximum absolute number of ASC-speck+ cells were detected on day 6 and day 7. Inflammatory cytokines were elevated on day 1 and declined thereafter, with exception of IL-18. Survival analysis showed that patients with lower absolute numbers of ASC-speck+ monocytes (<1,650 cells/ml) on day 6 had a lower probability to survive, with a hazard ratio (HR) of 10.178. Thus, the frequency of ASC-speck+ monocytes on day 6 after onset of sepsis may serve to identify patients at risk of death from sepsis.