Using ATAC-Seq to investigate the impact of vaccination on the epigenome

We used a mouse model to investigate whether live (BCG) and non-live (DTPw) vaccines differentially reprogram trained immune responses and to investigate whether immunisation with DTPw altered susceptibility to sepsis. We found that compared to BCG-immunised mice, DTPw immunisation led to altered monocyte and dendritic cell (DC) cytokine responses to subsequent secondary stimuli, as well as genome-wide changes to chromatin accessibility in DCs. These effects were evident months after immunisation and are consistent with different programs of trained immunity being induced by live versus non-live vaccines. Overall design: There are 12 samples total from 12 individual mice at one timepoint. 5 with each vaccine (BCG and DTPw) and 2 not vaccinated which are referred to as mock. Dendritic cells from these were subjected to ATAC-Seq.