Monocyte and lymphocyte activation in bipolar disorder: a new piece in the puzzle of immune dysfunction in mood disorders

Int J Neuropsychopharmacol. 2014 Oct 31;18(1):pyu021. doi: 10.1093/ijnp/pyu021.

Abstract

Background: This study tested the hypothesis that the low-grade inflammation presented in patients with bipolar disorder (BD) is associated with expansion of activated T cells, and this activated state may be due to a lack of peripheral regulatory cells.

Methods: Specifically, we investigated the distribution of monocytes and lymphocyte subsets, and investigated Th1/Th2/Th17 cytokines in plasma by flow cytometry. Twenty-one BD type I patients and 21 age- and sex-matched controls were recruited for this study.

Results: BD patients had increased proportions of monocytes (CD14+). Regarding lymphocyte populations, BD patients presented reduced proportions of T cells (CD3+) and cytotoxic T cells (CD3+CD8+). BD patients also exhibited a higher percentage of activated T CD4+CD25+ cells, and a lower percentage of IL-10 expressing Treg cells.

Conclusions: Our data shed some light into the underlying mechanisms involved with the chronic low-grade inflammatory profile described in BD patients.

Keywords: bipolar disorder; cytokines; lymphocytes; mania; monocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bipolar Disorder / blood*
  • Bipolar Disorder / immunology*
  • Blood Chemical Analysis
  • Cytokines / blood
  • Female
  • Flow Cytometry
  • Humans
  • Interleukin-10 / metabolism
  • Logistic Models
  • Lymphocyte Activation / immunology*
  • Male
  • Middle Aged
  • Monocytes / immunology*
  • T-Lymphocytes, Regulatory / immunology

Substances

  • Cytokines
  • IL10 protein, human
  • Interleukin-10