Transcriptome profile of memory phenotype CD8 T cells are shaped by overexpression of CD103

The CD8 T cells in the peripheral tissues maintained as a mixture of naïve and memory-phenotype in the steady state, while the mechanism how the balance of naïve and memory-phenotype CD8 T cells is controlled remains unclear. Here, we report that integrin CD103 plays critical role in this process. CD103 is differentially expressed on peripheral CD8 T cells with highest expression on naïve CD8 T cells (Ly6C–CXCR3–) and lowest expression on memory-phenotype CD8 T cells (Ly6C+CXCR3+). To understand the biological significance of CD103 downregulation on memory-phenotype CD8 T cells, we generated transgenic mice that overexpress CD103 under the control of the human CD2 promoter/enhancer so that CD103 is constitutively expressed on all T lineage cells (CD103Tg), and we found that memory-phenotype CD8 T cells are accumulated in CD103Tg mice. Therefore, we performed RNA sequencing on sorted memory-phenotype CD8 T cells from WT and CD103Tg mice to elucidate the molecular mechanism how forced expression of CD103 promotes accumulation of memory-phenotype CD8 T cells. Transcriptome analysis of Ly6C+CXCR3+ CD8 T cells sorted from lymph node of WT (C57BL/6) and CD103Tg mice