In vitro Homeostatic Proliferation of Human CD8 T Cells

Abstract

Long-lived T-cell–mediated immunity requires persistence of memory T cells in an antigen-free environment while also maintaining a heightened capacity to recall effector functions. Such antigen-independent homeostatic proliferation is mediated in part by the common gamma-chain cytokines IL-7 and IL-15. To further explore the mechanisms governing maintenance of effector functions in long-lived memory T cells during antigen-independent proliferation, human naïve and memory CD8 T cells can be sorted from peripheral blood mononuclear cells (PBMCs), labeled with the proliferation-tracking dye carboxyfluorescein succinimidyl ester (CFSE), and then purified based on their levels of cell division. This allows investigators to assess differences in the desired molecular target in cells that have undergone cytokine-driven proliferation. We provide here a protocol for assessing epigenetic programs in divided and undivided human naïve and memory CD8 T cells following 7 days in culture with IL-7 and IL-15 to illustrate how this approach can shed light on the mechanism(s) that governs the preservation of effector functions during homeostasis of long-lived memory CD8 T cells.

Integrative Epigenomic and Transcriptomic Analysis Reveals Robust Metabolic Switching in the Brain During Intermittent Fasting

“…Histone modifications induced by environmental influences have been reported to be stable throughout somatic cell division (Abdelsamed et al, 2018;Almouzni and Cedar, 2016;Gensous et al, 2019;Pal and Tyler, 2010;Vickers, 2014). Hence, we investigated whether the effects of IF on H3K9me 3 were maintained following refeeding.…”