Identification of Th1- and Th2-speciric genes by microarray analysis

CD4(+) helper T (Th) cells are subdivided into Th1 and Th2 cells in terms of their differential cytokine production pattern. These cells are key immunoregulatory cells in host defense mechanisms. Therefore, identification of differential gene expression in Th1 and Th2 cells is crucial for immunomodulation. Here we describe identification of Th1- or Th2-specific genes by DNA microarray analysis. We prepared mRNA from anti-CD3 mAb stimulated or unstimulated Th1 and Th2 cells, then gene expression profiles were analyzed by using a microarray spotted with 8,700 EST clones. We detected preferential expression of 57 genes in Th1 cells and 37 genes in Th2 cells. By semi-quantitative RT-PCR analysis, we identified 11 genes specifically expressed in Th1 cells, and 7 genes in Th2 cells. These genes may contribute to the differentiation and function of helper T cells and thereby regulation of immune response. Further analysis would help to develop a method to modulate immune response.