T CELL IMMUNITY TO RESPIRATORY VIRUS INFECTIONS

呼吸道病毒感染是全球发病率和死亡率的主要原因。 CD8+细胞毒性T淋巴细胞（CTL）已被证明在控制原发性感染中发挥核心作用，并代表了改进目前疫苗的重要目标，旨在强调针对这类病毒的细胞应答。 在目前的提案中，我们利用两种成熟的呼吸道病毒感染模型（仙台病毒和流感病毒）来研究记忆CD8+ T细胞的回忆。 初步数据显示，在仙台病毒和流感病毒感染后，不仅在脾中，而且在肺组织和灌洗液中都可以发现大量的抗原特异性T细胞。 有趣的是，在肺中的记忆性CD8+ T细胞与在脾中观察到的记忆性CD8+ T细胞在CD8+ T细胞中的表型和频率方面不同。该提案的基本假设是，肺部的记忆性CD8+ T细胞对继发性感染期间的快速回忆反应做出了重大贡献。 这一假设将通过（I）表征从呼吸道病毒感染恢复后在肺中持续存在的抗原特异性CD8+记忆T细胞，以及（II）确定不同记忆细胞群体对回忆反应的相对贡献来检验。

Respiratory virus infections are a major cause of morbidity and mortality worldwide. CD8+ cytotoxic T lymphocytes (CTL) have been shown to play a central role in controlling primary infection and represent an important target for improving current vaccines designed to emphasize cellular responses against this class of viruses. In the current proposal, we take advantage of two well-established models of respiratory virus infections (Sendai virus and influenza virus) to investigate the recall of memory CD8+ T cells. Preliminary data show that substantial numbers of antigen-specific T cells can be found not only in the spleen, but also in the lung tissue and lavage following both Sendai virus and influenza virus infection. Interestingly, memory CD8+ T cells in the lung differ from those observed in the spleen in terms of phenotype and frequency among CD8+ T cells. The underlying hypothesis of the proposal is that memory CD8+ T cells in the lung make a substantial contribution to the rapid recall response during secondary infection. This hypothesis will be tested by (I) characterizing antigen-specific CD8+ memory T cells that persist in the lungs following recovery from respiratory virus infection, and (II) determining the relative contributions of distinct populations of memory cells to the recall response.