Systems-level temporal immune- metabolic profile in Crimean-Congo hemorrhagic fever virus infection

Crimean-Congo hemorrhagic fever (CCHF) caused by CCHF virus (CCHFV) is one of the epidemic-prone diseases prioritized by the World Health Organisation as public health emergency with an urgent need for accelerated research. lhe trajectory of host response against CCHFV is multifarious and remains unknown. Here, we reported the temporal spectrum of pathogenesis following the CCHFV infection using genome-wide blood transcriptomics analysis followed by advanced systems biology analysis, tempo-ral immune- pathogenic alterations, and context- specific progressive and postinfection genome-scale metabolic models (GSMM) on samples collected during the acute (T0), early convalescent (T1), and convalescent-phase (T2). lhe interplay between the retinoic acid- inducible gene - I- like/nucleotide- bindingoligomerization domain-like receptor and tumor necrosis factor signaling governed the trajectory of antiviral immune responses. lhe rearrangement of intracellular metabolic fluxes toward the amino acid metabolism and metabolic shift toward oxidative phosphorylation and fatty acid oxidation during acute CCHFV infection determine the pathogenicity. lhe upregulation of the tricarboxylic acid cycle during CCHFV infection, compared to the noninfected healthy control and between the severity groups, indicated an increased energy demand and cellular stress. lhe upregulation of glycolysis and pyruvate metabolism potentiated energy generation through alternative pathways associated with the severity of the infection. lhe downregulation of metabolic processes at the convalescent phase identified by blood cell transcriptomics and single-cell type proteomics of five immune cells (CD4+ and CD8+ T cells, CD14+ mono-cytes, B cells, and NK cells) potentially leads to metabolic rewiring through the recovery due to hyperactivity during the acute phase leading to post-viral fatigue syndrome.

Automated summary

This study analyzed the trajectory of host response and metabolic changes following CCHFV infection, revealing that antiviral immune responses are regulated by genes and signaling pathways. The reorganization of metabolism during the acute phase contributes to pathogenicity, while downregulated metabolic processes during the convalescent phase may lead to metabolic rewiring.