Cognitive Behavioral Therapy Affects Function of the Immune System

Josie Gilbert* and Elizabeth Engler-Chiurazzi, Department of Neuroscience, West Virginia University, Morgantown, WV 26506

Field (Broad Category): Neuroscience (Health Sciences) 

Student’s Major: Neuroscience 

Major depressive disorder, characterized by anhedonia, low mood, decreased motivation, and in some cases, suicidality, is a major public health concern. Indeed, MDD is the fourth leading cause of disability worldwide and has an economic burden in the United States of $210 billion per year. A growing body of evidence supports the connection between dysfunction of the immune system and MDD, in particular a proinflammatory response; however, the mechanism by which immune system activity affects MDD is unclear. Several behavioral interventions are known to abate depressive symptoms, so we would expect biomarkers indicative of an immune response to change following successful treatment. I hypothesize that if CBT is given to individuals with MDD, there should be a trend towards an anti-inflammatory response and decreased levels of pro-inflammatory cytokines in blood serum following treatment. To examine this, a literature search was conducted on studies that measured cytokine levels in blood before and after treatment with CBT. These studies measured several biomarkers, including IL-6 and TNF-α, predominantly pro-inflammatory cytokines, and IL-10, a predominantly anti-inflammatory cytokine. A general trend of IL-6 and TNF-α reduction following CBT occurred across most studies, while the effect of CBT on IL-10 is inconsistent, supporting the hypothesis that there is a diminished presence of circulating pro-inflammatory cytokines following CBT but not consistently supporting the hypothesis that circulating anti-inflammatory cytokines are increased following CBT. Additional research into immune system changes before and after behavioral interventions could lead to predictions of treatment efficacy and the development of novel therapeutic drugs. 

Funding: EEC (K01 MH117343 NATIONAL; U54 GM104942 NATIONAL; WVU Research Office STATE), JWS (P20 GM10998 NATIONAL), and EEC/JWS (Brain Health Project PRIVATE COMPANY; WVU College of Medicine Funds STATE). 

Program/mechanism supporting research/creative efforts: WVU's Research Apprenticeship Program (RAP) & accompanying HONR 297-level course