Longitudinal Immune Profiling and Corticosteroid Modulation of the Immediate Innate Immune Response to ChAdOx1 nCoV-19

ChAdOx1 nCoV-19, a chimpanzee adenovirus (ChAd)-vector vaccine expressing the SARS-CoV-2 spike protein, has elicited robust immunological responses in large populations. Despite its proven efficacy and safety, some recipients have reported immediate inflammatory reactions post-vaccination. We comprehensively examined the immune landscape following ChAdOx1 nCoV-19 vaccination based on the epigenomic profiles of monocytes. Glucocorticoids are wildly used as steroid anti-inflammatory drugs to modify acute and chronic inflammation. Recently, dexamethasone is used to modify inflammation in COVID19 and side-effects after COVID19 vaccination. ChAdox1 nCoV-19 induces interferon responses and inflammation in human. In addition to IFNa, TNF and IL1b treatment to mimic inflammatory environment gives general effects of glucocorticoids in complex inflammatory context. Overall design: Peripheral blood samples were obtained from five healthy volunteers at four post-ChAdOx1 nCoV-19 vaccination time points: days 0 (baseline), 1, 3, and 14. To mimic COVID19 and inflammatory environment, we pre-treated combination of IFNa(1000U), TNF(20ng), and IL1b(20ug) to 1 million of PBMC derived CD14+ cells with 100mg/ml of MCSF. In order to investigate glucocorticoid effects in chromatin-remodeling level, we treated 100nM of Dexamethasone to each condition at 3h after cytokine treatment. Cells are havested 12h after dexamethasone treatment.