β-arrestin 2-mediated immune suppression induced by chronic stress.

Objective: Stress, either physical or psychological, can modulate immune function. However, the mechanisms associated with stress-induced immune suppression remain to be elucidated. beta-Arrestin 2 serves as adaptor, scaffold, and/or signal transducer. The role of beta-arrestin 2 in stress-induced immune suppression is not known yet. Methods/Results: Here, we demonstrate that beta-arrestin 2 deficiency in mice increases the sensitivity to the chronic stress-induced reduction in the number of splenocytes. Interestingly, the stress-induced suppression of T helper-type (Th) 1 cytokines and the increased production of Th2 cytokines were greatly enhanced in beta-arrestin 2-deficient mice compared with wildtype mice. Moreover, inhibition of PI3K in beta-arrestin 2-deficient mice exerts an additive effect on the stress-induced reduction in the number of splenocytes. Conclusion: Our study demonstrates that a deficiency in beta-arrestin 2 augments stress-induced immune suppression. Copyright (C) 2011 S. Karger AG, Basel