Iminosugar MON-DNJ modulation of transciptomic response to dengue virus and LPS in primary human macrophages

Protocols for the treatment of sepsis and septic shock are restricted to early administration of appropriate antibiotics and supportive organ care. To date, there has been limited success in addressing the characteristically dysregulated host response once it is underway. Furthermore, virus-induced sepsis remains poorly appreciated, and treatment strategies are similarly limited to supportive measures. Prior in vitro and murine studies demonstrate antiviral efficacy of iminosugars against diverse viral pathogens, but translational approaches to humans are missing. Here we show successful iminosugar-mediated inhibition of dengue virus, bacterial lipopolysaccharide, and fungal antigen stimulated cytokine responses in human macrophages. Iminosugar treatment mediated a sustained reduction in oxidative stress and the secretion of proinflammatory cytokines, particularly IFN-g and TNF-a. Transcriptome analysis suggests that the mechanism behind this reduction involves endoplasmic reticulum (ER) stress via early, pathogen-independent induction of a robust unfolded protein response (UPR). Based on these findings, we propose that iminosugars have the potential to fill the treatment gap in controlling symptoms and complications of a wide variety of inflammatory disorders associated with excessive cytokine secretion. Primary human monocyte-derived macrophages from 4 donors were matured in the presence of recombinant human IL-4 (25 ng/mL) for 3 days. After 3 days, media was removed and samples were infected with dengue virus (DENV-2 16681) at MOI of 1 or treated with lipopolysaccharide (Salmonella enterica, 200 ng/mL) for 90 minutes. Uninfected controls were incubated in X-VIVO medium. Virus was removed and samples were treated with N9-methoxynonyl-deoxynojirimycin (MON-DNJ, 25 μM) or untreated. LPS-treated samples were diluted to a final concentration of 100 ng/mL LPS for the time period following the initial 90 minute incubation and were treated with MON-DNJ or untreated. Samples were collected at 6 hours and 24 hours post-initiation of infection for a total of 12 treatments in biological quadruplicate for 48 total samples.