t-helper cell type-1 transcription factor t-bet is down-regulated in type 1 diabetes

T cells have been identified as key players in the pathogenesis of type 1 diabetes. however, the exact role of t-cell subpopulations in this pathway is presently unknown. the purpose of this study was to assess the expression pattern of two lineage-specifying transcription factors gata-3 and t-bet, which are important in t helper type 1 (th1) and th2 cell development, respectively. gene expression analysis of peripheral blood mononuclear cells (pbmcs) was performed using reverse transcription-quantitative polymerase chain reaction (rt-qpcr). plasma levels of ifn-γ and il-4 were also determined by elisa. t-bet and ifn-γ gene expression was significantly lower in patients group compared with healthy controls (p<0.05). the expression of gata-3 was relatively similar in patients and controls; however, il-4 mrnas were significantly increased in the pbmcs from patients as compared with normal controls (p<0.05). in addition, a marked increase in plasma il-4 levels were observed in patient group compared with controls (p<0.001). to the contrary, ifn-γ protein levels were decreased in patients in comparison with controls (p<0.001). these data suggest additional implications of the role of th1/th2 imbalance for the immunopathogenesis of type 1 diabetes.