Heat stress and immune response phenotype affect DNA methylation in blood mononuclear cells from Holstein dairy cows

Our goal was to identify epigenetic differences between high and low immune responder cows in response to heat stress. We report genome-wide DNA methylation of blood mononuclear cells (BMCs) isolated from high and low cows, before and after in vitro heat stress. We identified differential methylation of promoter regions associated with a variety of biological processes including immune function, stress response, apoptosis, and cell signalling. The specific differentially methylated promoter regions differed between samples from high and low cows, and results revealed pathways associated with cellular protection during heat stress. Overall design: Examination of DNA methylation in blood mononuclear cells from bovine