Enhanced Immune Activation Following Acute Social Stress Among Adolescents With Early-Life Adversity

Abstract

Background: Early-life adversity (ELA) has been linked to higher depression risk across the life span and chronic inflammatory conditions that contribute to earlier mortality. In this study, we characterized innate immune responses to acute social stress in a community sample of adolescents (mean age = 13.9 ± 1.6 years; 46.4% female) as a potential pathway linking ELA and depression pathogenesis. Methods: Parents reported their child’s exposure to 9 ELAs, and adolescents participated in the Trier Social Stress Test for Children, with blood collected immediately before and then at 60 and 90 minutes thereafter. Overall, 65 adolescents had complete data for analysis of stress-induced changes in gene expression and 84 adolescents had complete data for circulating inflammatory markers. Results: Relative to adolescents exposed to no ELA (11.9%) or low ELA (ELA = 1−3; 67.9%), those exposed to high ELA (ELA = 4+; 20.2%) showed larger stress-associated increases in expression of both proinflammatory and innate antiviral gene transcripts in circulating blood. Consistent with a potential mediating role of sympathetic nervous system activity, promoter-based bioinformatics analyses implicated CREB transcription factor activity in structuring observed gene expression differences. These effects were accompanied by a smaller initial but protracted increase in circulating interleukin 6 in adolescents with high ELA. Conclusions: Results are consistent with the hypothesis that ELA may enhance cellular and gene regulatory reactivity to stress, which may, in turn, increase vulnerability to depression and other inflammation-related disease processes.

Keywords

• Adolescence
• Depression
• Early-life adversity
• Inflammation
• Innate immune system
• Social stress