Early recruitment of neutrophils from the blood to sites of tissue infection is a hallmark of innate immune responses. However, little is known about the mechanisms by which apoptotic neutrophils are cleared in infected tissues during resolution and the immunological consequences of in situ efferocytosis. Using intravital multiphoton microscopy, we show previously unrecognized motility patterns of interactions between neutrophils and tissue-resident phagocytes within the influenza-infected mouse airway. Newly infiltrated inflammatory monocytes become a chief pool of phagocytes and play a key role in the clearance of highly motile apoptotic neutrophils during the resolution phase. Apoptotic neutrophils further release epidermal growth factor and promote the differentiation of monocytes into tissue-resident antigen-presenting cells for activation of antiviral T cell effector functions. Collectively, these results suggest that the presence of in situ neutrophil resolution at the infected tissue is critical for optimal CD8⁺ T cell–mediated immune protection.

中性粒细胞早期从血液募集到组织感染部位是先天免疫反应的标志。然而，人们对感染组织中凋亡中性粒细胞在消退过程中被清除的机制以及原位胞吞作用的免疫学后果知之甚少。使用活体多光子显微镜，我们显示了流感感染小鼠气道内中性粒细胞和组织驻留吞噬细胞之间相互作用的先前未被识别的运动模式。新浸润的炎性单核细胞成为吞噬细胞的主要池，并在消退阶段清除高度活动的凋亡中性粒细胞中发挥关键作用。凋亡的中性粒细胞进一步释放表皮生长因子并促进单核细胞分化为组织驻留的抗原呈递细胞，从而激活抗病毒T细胞效应功能。总的来说，这些结果表明，受感染组织中中性粒细胞原位消退的存在对于最佳 CD8 ⁺ T 细胞介导的免疫保护至关重要。