Chronic exposure to stress has detrimental effects on the adaptive immune response. Studies in vitro show that exposure of norepinephrine (NE), a stress hormone, decreases proliferation and functionality of T cells. T cells consist of several different types of cells and each of them serves distinct functions during an immune response. It is unknown how NE reduces functionality of T cells and whether NE has different impact on different types of T cells. Here, we assessed the effect of NE on CD8 T cell function in humans in vitro. We found that not all subsets of CD8 T cells respond the same to NE exposure; memory cells including central memory (Tcm) and effector memory (Tem) were more significantly affected by NE compared to naïve (Tn) CD8 T cells in terms of gene expression of cytokines (IL-2, IFNG, and TNF) important to proliferation and function in the adaptive immune response. Furthermore, expression of NE receptor, Beta-2 adrenergic receptor (B2AR), was higher in freshly isolated memory CD8 T cells (both Tcm and Tem) compared to Tn CD8 T cells. Together these findings show that memory CD8 T cells are more susceptible to NE induced reduction of cytokine production. Currently we are analyzing the effect of NE on general gene expression in Tcm and Tem cells as well as examining histone modifications in these cytokine loci to determine if NE effect via chromatin changes in CD8 T cells.
