S. aureus is a leading cause of bacterial infection. Macrophages, the first line of defence in the human immune response, phagocytose and kill S. aureus but the pathogen can evade these responses. Therefore, the exact role of macrophages is incompletely defined. We develop a mathematical model of macrophage - S. aureus dynamics, built on recent experimental data. We demonstrate that, while macrophages may not clear infection, they significantly delay its growth and potentially buy time for recruitment of further cells. We find that macrophage killing is a major obstacle to controlling infection and ingestion capacity also limits the response. We find bistability such that the infection can be limited at low doses. Our combination of experimental data, mathematical analysis and model fitting provide important insights in to the early stages of S. aureus infections, showing macrophages play an important role limiting bacterial replication but can be overwhelmed with large inocula.

中文翻译：

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数学模型显示巨噬细胞会延迟金黄色葡萄球菌的复制，但杀菌能力的限制限制了细菌的清除。


金黄色葡萄球菌是细菌感染的主要原因。巨噬细胞是人体免疫反应的第一道防线，吞噬并杀死金黄色葡萄球菌，但病原体可以逃避这些反应。因此，巨噬细胞的确切作用尚不完全确定。我们根据最近的实验数据开发了巨噬细胞 - 金黄色葡萄球菌动力学的数学模型。我们证明，虽然巨噬细胞可能无法清除感染，但它们会显着延迟其生长，并可能为招募更多细胞赢得时间。我们发现巨噬细胞杀伤是控制感染的主要障碍，摄入能力也限制了反应。我们发现双稳定性使得感染可以在低剂量下受到限制。我们将实验数据、数学分析和模型拟合相结合，为金黄色葡萄球菌感染的早期阶段提供了重要的见解，表明巨噬细胞在限制细菌复制方面发挥着重要作用，但可能被大量接种物淹没。