Human respiratory syncytial virus (RSV) is a pneumovirus that causes severe infections in infants worldwide. Despite intensive research, safe and effective vaccines against RSV have remained elusive. The main reason is that RSV infection of children previously immunized with formalin-inactivated-RSV vaccines has been associated with exacerbated pathology, a phenomenon called RSV vaccine-enhanced respiratory disease. In parallel, despite the high RSV prevalence, only a minor proportion of children develop severe diseases. Interestingly, variation in the immune responses against RSV or following RSV vaccination could be linked with differences of exposure to microbes during childhood. Gammaherpesviruses (γHVs), such as the Epstein-Barr virus, are persistent viruses that deeply influence the immune system of their host and could therefore affect the development of pneumovirus-induced immunopathologies for the long term. Here, we showed that a previous ɣHV infection protects against both pneumovirus vaccine-enhanced disease and pneumovirus primary infection and that CD8 T cells are essential for this protection. These observations shed a new light on the understanding of pneumovirus-induced diseases and open new perspectives for the development of vaccine strategies.

中文翻译：

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γ 疱疹病毒许可 CD8 T 细胞保护宿主免受肺炎病毒诱导的免疫病理。

人类呼吸道合胞病毒 (RSV) 是一种肺病毒，可导致全世界婴儿严重感染。尽管进行了深入研究，但安全有效的 RSV 疫苗仍然难以捉摸。主要原因是先前用福尔马林灭活 RSV 疫苗免疫的儿童的 RSV 感染与恶化的病理有关，这种现象称为 RSV 疫苗增强性呼吸道疾病。同时，尽管 RSV 流行率很高，但只有一小部分儿童会患上严重疾病。有趣的是，针对 RSV 或 RSV 疫苗接种后免疫反应的变化可能与儿童时期接触微生物的差异有关。伽马疱疹病毒 (γHV)，例如爱泼斯坦-巴尔病毒，是持久性病毒，深刻影响宿主的免疫系统，因此可能长期影响肺病毒诱导的免疫病理学的发展。在这里，我们表明先前的 ɣHV 感染可以预防肺炎病毒疫苗增强型疾病和肺炎病毒原发性感染，并且 CD8 T 细胞对于这种保护至关重要。这些观察结果为了解肺炎病毒引起的疾病提供了新的思路，并为疫苗策略的开发开辟了新的视角。