Mobilization of gammadelta T lymphocytes in response to psychological stress, exercise, and beta-agonist infusion

Research output: Contribution to journalArticle

Abstract

The mobilization of cytotoxic lymphocytes, such Natural Killer (NK) cells and CD8+ T cells, during stress and exercise is well documented in humans. However, humans have another cytotoxic lymphocyte subset that has not been studied in this context: the Gamma Delta (gammadelta)T lymphocyte. These cells play key roles in immune processes including the elimination of bacterial infection, wound repair and delayed-type hypersensitivity reactions. The current study investigated the effects of stress, exercise, and beta-agonist infusion on the mobilization of gammadelta T lymphocytes. Three separate studies compared lymphocytosis in response to an acute speech stress task (n =29), high (85%Wmax) and low (35%Wmax) intensity concentric exercise (n = 11), and isoproterenol infusion at 20ng/min/kg and 40ng/min/kg (n = 12). Flow cytometric analysis was used to examine lymphocyte subsets. gammadelta T lymphocytes were mobilized in response to all three tasks in a dose-dependent manner; the extent of mobilization during the speech task correlated with concomitant cardiac activation, and was greater during higher intensity exercise and increased dose of beta-agonist infusion. The mobilization of gammadelta T lymphocytes was greater (in terms of % change from baseline) than that of CD8+ T lymphocytes and less than NK cells. This study is the first to demonstrate that gammadelta T cells are stress-responsive lymphocytes which are mobilised during psychological stress, exercise, and beta-agonist infusion. The mobilization of these versatile cytotoxic cells may provide protection in the context of situations in which antigen exposure is more likely to occur.

Details

Original languageEnglish
Pages (from-to)823-829
Number of pages7
JournalBrain, Behaviour, and Immunity
Volume23
Issue number6
Publication statusPublished - 21 Mar 2009

Keywords

  • Sympathetic reactivity, Lymphocytosis, Adaptive immunity, T lymphocytes, Infusion, Exercise, Acute stress, Adrenergic, Isoproterenol, Innate immunity