Hepatic Interleukin-7 Expression Regulates T Cell Responses

作者：Sawa Yukihisa; Arima Yasunobu; Ogura Hideki; Kitabayashi Chika; Jiang Jing Jing; Fukushima Toru; Kamimura Daisuke; Hirano Toshio; Murakami Masaaki^*

来源：Immunity, 2009, 30(3): 447-457.

DOI：10.1016/j.immuni.2009.01.007

Systemic cytokine activity in response to Toll-like receptor (TLR) signaling induces the expression of various proteins in the liver after infections. Here we show that Interleukin-7 (IL-7), the production of which was thought to occur at a constant rate in vivo, was a hepatically expressed protein that directly controled T cell responses. Depletion of IL-7 expression in the liver abrogated several TLR-mediated T cell events, including enhanced CD4( ) T cell and CD8( ) T cell survival, augmented CD8( ) T cell cytotoxic activity, and the development of experimental autoimmune encephalitis, a Th17 cell-mediated autoimmune disease. Thus, T cell responses are regulated by hepatocyte-derived IL-7, which is expressed in response to TLR signaling in vivo. We suggested that TLR-induced IL-7 expression in the liver, which is an acute-phase response, may be a good diagnostic and therapeutic target for efficient vaccine developments and for conditions characterized by TLR-mediated T cell dysregulation, including autoimmune diseases.

• 出版日期2009-3-20