Therapeutic use of IL-2 to enhance

antiviral T-cell responses in vivo

Speaker: 蘇玲瑤

Commentator: 黎煥耀  老師

Time: 2003/10/22 13:00~14:00

Place: Room 601

Abstract

    Interleukin-2 (IL-2) is a cytokine secreted by activated T lymphocytes that regulates the proliferation and differentiation of lymphocytes. IL-2 is currently used to enhance T-cell responses to viral and tumor antigens in patients, including those with HIV or metastatic cancer. However, IL-2 may have both positive and negative effects on T cells. To better understand theses opposing results are due to IL-2 acting differently on T cells depending on their stage of differentiation, the authors examined the effects of IL-2 therapy during the expansion, contraction and memory phases of the T-cell response in lympocytic choriomeningitis virus (LCMV)-infected mice. Additional IL-2 in expansion phase sustained expression of the high-affinity IL-2R but did not enhance CD8⁺ T cell expansion. Furthermore, virus-specific CD4⁺ T cells reduced in IL-2-treated mice. In contrast, IL-2 treatment during the death phase of the T-cell response resulted in increased proliferation and survival of virus-specific T cells. Moreover, IL-2 therapy increased proliferation of resting memory T cells and enhanced T-cell response in mice that harbor a persistent viral infection. That corresponded to an increased ability to control virus. In short, the timing of IL-2 administration and differentiation status of the T-cell are critical parameters in designing IL-2 therapies.

References

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3.      Blattman, J.N. et al. Therapeutic use of IL-2 to enhance antiviral T-cell responses in vivo. Nat. Med. 9,540-547 (2003).