Protection from Respiratory Virus Infections Can Be Mediated by Antigen-Specific Cd4+ T Cells That Persist in the Lungs

作者：Robert J. Hogan, Weimin Zhong, Edward J. Usherwood, Tres Cookenham, Alan D. Roberts, David L. Woodland · 发表于：The Journal of Experimental Medicine · 年份：2001 · DOI：10.1084/jem.193.8.981 · 被引用次数：289 · 研究领域：Immune Cell Function and Interaction、T-cell and B-cell Immunology、Immunotherapy and Immune Responses

Although CD4(+) T cells have been shown to mediate protective cellular immunity against respiratory virus infections, the underlying mechanisms are poorly understood. For example, although phenotypically distinct populations of memory CD4(+) T cells have been identified in different secondary lymphoid tissues, it is not known which subpopulations mediate protective cellular immunity. In this report, we demonstrate that virus-specific CD4(+) T cells persist in the lung tissues and airways for several months after Sendai virus infection of C57BL/6 mice. A large proportion of these cells possess a highly activated phenotype (CD44(hi), CD62L(lo), CD43(hi), and CD25(hi)) and express immediate effector function as indicated by the production of interferon gamma after a 5-h restimulation in vitro. Furthermore, intratracheal adoptive transfer of lung memory cells into beta2m-deficient mice demonstrated that lung-resident virus-specific CD4(+) T cells mediated a substantial degree of protection against secondary virus infection. Taken together, these data demonstrate that activated memory CD4(+) T cells persisting at mucosal sites play a critical role in mediating protective cellular immunity.