T-bet deficient mice exhibit resistance to stress-induced development of depression-like behaviors.

T-bet, a Th1-specific T-box transcription factor, regulates Th1 development by inducing endogenous Th1 cytokines and IFN-γ. This study was conducted to determine if T-bet knockout mice exhibit resistance to stress-induced development of depression-like behaviors. The T-bet knockout mice significantly reduced depressive-like behaviors provoked by repeated restraint stress in an elevated plus-maze test (EPM), tail suspension test (TST), and forced swim test (FST). Moreover, stress-induced elevations of the pro-inflammatory cytokines were attenuated in T-bet deficient group. These results suggest that T-bet directly mediated stress-induced depression. Therefore, understanding T-bet function during stress represents an additional treatment strategy for depression.