Direct IL-6 Signals Maximize Protective Secondary CD4 T Cell Responses against Influenza

作者：Strutt Tara M^*; McKinstry Karl Kai^*; Kuang Yi; Finn Caroline M; Hwang Ji Hae; Dhume Kunal; Sell Stewart; Swain Susan L

来源：The Journal of Immunology, 2016, 197(8): 3260-3270.

DOI：10.4049/jimmunol.1600033

Memory T cells can often respond against pathogens that have evaded neutralizing Abs and are thus key to vaccine-induced protection, yet the signals needed to optimize their responses are unclear. In this study, we identify a dramatic and selective requirement for IL-6 to achieve optimal memory CD4 T cell recall following heterosubtypic influenza A virus (IAV) challenge of mice primed previously with wild-type or attenuated IAV strains. Through analysis of endogenous T cell responses and adoptive transfer of IAV-specific memory T cell populations, we find that without IL-6, CD4(+), but not CD8(+), secondary effector populations expand less and have blunted function and antiviral impact. Early and direct IL-6 signals to memory CD4 T cells are required to program maximal secondary effector responses at the site of infection during heterosubtypic challenge, indicating a novel role for a costimulatory cytokine in recall responses.

• 出版日期2016-10-15