Epigenetic Differences in IFN and IL-4 Promoter Regions of Dairy Cows Identified With Type 1 and 2 Immune Response Bias

Abstract Text: Over the past two decade epigenetics has influenced the investigation of disease susceptibility. DNA methylation has been extensively studied in CD4+ T-cell immune responses (IR) and it has been shown that specific DNA methylation sites within cytokine promoters influence cytokine production. The objective of this study was to determine the role of DNA methylation at cytokine promoters in high (H) antibody- (AMIR) or H cell- (CMIR) mediated immune responses in cows. CD4+ T-cells were isolated from H-AMIR (n=10) and H-CMIR (n=11) cows three weeks after calving. DNA was collected for bisulfite pyrosequencing to determine DNA methylation patterns. T-cells from H-CMIR cows produced more IL-4 and IFN-γ than cells from H-AMIR cows. DNA methylation at the IL4 and IFNG promoter ranged from 30-70% methylation. Interestingly, H-CMIR cows had lower CpG methylation overall at the IFNG promoter than H-AMIR, which correlated with high IFNγ production.

Keywords:

dairy cattle

epigenetics

health