甲型流感病毒 (IAV) 感染构成了持续的全球健康挑战，需要细致入微地掌握宿主免疫反应，以采取最佳干预措施。虽然衰老、免疫衰老和 IAV 之间的相互作用被认为是严重下呼吸道感染的关键，但特定患者属性在 IAV 感染期间形成先天免疫反应和炎性体活动中的作用仍然没有得到充分研究。在这项研究中，我们利用 H3N2 IAV 人类肺组织的离体感染模型来辨别患者人口统计学、IAV 核蛋白 (NP) 表达、Toll 样受体 (TLR) 谱、PD-1/PD-L1 标记物、我们的队列由 2018 年至 2019 年期间接受视频辅助胸腔镜手术的 30 名成年患者组成。术后肺组织暴露于 H3N2 IAV 进行离体感染，并使用流式细胞术分析随后的免疫反应。我们观察到肺细胞内明显的 IAV 活性，如两种上皮细胞中明显的 NP 上调所示 (P = 0.022)与对照组相比，IAV 暴露组中的巨噬细胞（P = 0.003）。值得注意的是，IL-2 水平与上皮细胞上 TLR1 表达和巨噬细胞上 PD-L1 标记物的变化相关。年龄成为调节因素，抑制先天免疫反应，白介素 2 和干扰素 γ 浓度降低就证明了这一点（均调整后 P < 0.05）。有趣的是，一组具有明显肿瘤坏死因子-α 模拟后感染的参与者（集群 1）与集群 2 和集群 3 中的对应参与者相比，细胞因子反应减弱（所有调整后的 P < 0.05）。集群 2 中的个体，其特征是巨噬细胞中模拟感染后的 NP 表达较低，与集群 3 中的个体相比，这些细胞上的 NP 和 TLR1-3 表达变化减少，白细胞介素 2 分泌变化减少。通过其升高的 NP 巨噬细胞表达来鉴定（所有调整后的 P < 0.05）。我们的工作阐明了患者因素、先天免疫和遭受离体 H3N2 IAV 暴露的肺组织中炎症反应的多方面相互作用，反映了真实世界的下呼吸道感染。虽然这些发现为定制治疗策略奠定了基础，但彻底验证和完善还需要补充研究。版权所有 © 2023 Huang、Wu、Hsieh、Lin、Hsieh、Huang、Yang、Tsao、Shih 和 Lee。

Influenza A virus (IAV) infection poses a persistent global health challenge, necessitating a nuanced grasp of host immune responses for optimal interventions. While the interplay between aging, immunosenescence, and IAV is recognized as key in severe lower respiratory tract infections, the role of specific patient attributes in shaping innate immune reactions and inflammasome activity during IAV infection remains under-investigated. In this study, we utilized an ex vivo infection model of human lung tissues with H3N2 IAV to discern relationships among patient demographics, IAV nucleoprotein (NP) expression, toll-like receptor (TLR) profiles, PD-1/PD-L1 markers, and cytokine production.Our cohort consisted of thirty adult patients who underwent video-assisted thoracoscopic surgery during 2018-2019. Post-surgical lung tissues were exposed to H3N2 IAV for ex vivo infections, and the ensuing immune responses were profiled using flow cytometry.We observed pronounced IAV activity within lung cells, as indicated by marked NP upregulation in both epithelial cells (P = 0.022) and macrophages (P = 0.003) in the IAV-exposed group relative to controls. Notably, interleukin-2 levels correlated with variations in TLR1 expression on epithelial cells and PD-L1 markers on macrophages. Age emerged as a modulating factor, dampening innate immune reactions, as evidenced by reduced interleukin-2 and interferon-γ concentrations (both adjusted P < 0.05). Intriguingly, a subset of participants with pronounced tumor necrosis factor-alpha post-mock infection (Cluster 1) showed attenuated cytokine responses in contrast to their counterparts in Cluster 2 and Cluster 3 (all adjusted P < 0.05). Individuals in Cluster 2, characterized by a low post-mock infection NP expression in macrophages, exhibited reduced variations in both NP and TLR1-3 expressions on these cells and a decreased variation in interleukin-2 secretion in comparison to their Cluster 3 counterparts, who were identified by their elevated NP macrophage expression (all adjusted P < 0.05).Our work elucidates the multifaceted interplay of patient factors, innate immunity, and inflammasome responses in lung tissues subjected to ex vivo H3N2 IAV exposure, reflecting real-world lower respiratory tract infections. While these findings provide a foundation for tailored therapeutic strategies, supplementary studies are requisite for thorough validation and refinement.Copyright © 2023 Huang, Wu, Hsieh, Lin, Hsieh, Huang, Yang, Tsao, Shih and Lee.