Pneumonia is a ubiquitous disease caused by viral and bacterial infections, characterized by high levels of reactive oxygen species in inflamed areas. Therapeutic strategies targeting reactive oxygen species levels in pneumonia have limited success due to the intricate nature of lung tissues and lung inflammatory responses. Here we describe an inhalable, non-invasive therapeutic platform composed of engineered cerium-based tannic acid nanozymes bound to a self-assembling peptide. In vitro and in vivo studies show that the nanozyme is internalized mostly by activated macrophages and epithelial cells in the inflamed sites. In the oxidative environments of a mouse model of viral pneumonia, nanozyme aggregates into catalytically active structures that reduce reactive oxygen species levels and inflammatory cytokine production and promote macrophage polarization to the prohealing (M2) phenotype. Moreover, the nanozyme attenuates bacterial inflammation and reduces tissue damage in a mouse viral pneumonia model with secondary bacterial infection. Overall, this nanozyme platform is a promising strategy for treating pneumonia and its associated conditions.

肺炎是一种由病毒和细菌感染引起的普遍疾病，其特征是发炎区域活性氧水平高。由于肺组织和肺部炎症反应的复杂性，针对肺炎中活性氧水平的治疗策略成功率有限。在这里，我们描述了一种可吸入、非侵入性的治疗平台，该平台由与自组装肽结合的工程化铈基单宁酸纳米酶组成。体外和体内研究表明，纳米酶主要由发炎部位的活化巨噬细胞和上皮细胞内化。在病毒性肺炎小鼠模型的氧化环境中，纳米酶聚集成催化活性结构，降低活性氧水平和炎性细胞因子的产生，并促进巨噬细胞极化为促愈合 （M2） 表型。此外，纳米酶可减轻继发性细菌感染小鼠病毒性肺炎模型中的细菌炎症并减少组织损伤。总体而言，这种纳米酶平台是治疗肺炎及其相关疾病的一种有前途的策略。