Immune Regulatory Markers in Clinical Cases of COVID-19

Abstract The objective of this research study is to profile anti-viral and pro-inflammatory cytokines, major histocompatibility complex (MHC) class I & II molecules and cell death markers in clinical cases of sepsis. Research study design included three patient cohorts namely, COVID-19 with sepsis (C19wSepsis, N=17), COVID-19 with no sepsis (C19NoSepsis, N=17) and sepsis alone (N=24). Healthy subjects served as controls (N=16). Serum samples derived from patient cohorts and control subjects were analyzed by ELISA for anti-viral and pro-inflammatory cytokines (IFN-gamma and IL-1beta), MHC class I (MHCA) & MHC class II (MHCDRb1) molecules and cell death markers. Data and statistical analyses were performed using GraphPad Prism 7.0. ELISA of serum samples identified a significant increase in serum IFN-gamma, MHCA and MHCDRb1 levels in C19wSepsis cohort compared to C19NoSepsis cohort and control subjects [p < 0.0001]. Although there was a significant increase in IL-1beta levels in serum samples of C19wSepsis compared to control subjects and sepsis alone cohort [p < 0.0005], the levels were comparable between C19wSepsis and C19NoSepsis cohorts [p >= 0.05]. Cell death markers, Caspase-3 and p62/SQSTM1, showed significantly altered levels between the three patient cohorts when compared to controls [p < 0.01]. Representative data from flow cytometry confirm ELISA results. Results from this study identify key immune regulatory markers in clinical cases of COVID-19.