Temporal and Spatial Characterization of Mononuclear Phagocytes in Circulating, Pulmonary Alveolar, and Interstitial Compartments in LPS-Induced Acute Lung Injury

Frontiers in Surgery

article

Qi Li¹  Guoan Xiang²  Shouchun Peng³  Wenjie Ji⁴ 

[1] Department of Tuberculosis, Beijing Chest Hospital, Capital Medical University;Department of Respiratory, The Third Medical Center of Chinese People's Liberation Army General Hospital;Department of Respiratory, Affiliated Hospital of Armed Police Logistic College;Institute of Cardiovascular Disease and Heart Center, Pingjin Hospital

关键词: acute lung injury;    lipopolysaccharide;    Ly6C;    alveolar macrophages;    interstitial macrophages;   

DOI  :  10.3389/fsurg.2022.837177

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

Peripheral circulating monocytes and resident macrophages are heterogeneous effector cells that play a critical role in the maintenance and restoration of pulmonary integrity. However, their detailed dynamic changes in lipopolysaccharide (LPS)-induced acute lung injury (ALI) remain unclear. Here, we investigated the impact of mononuclear phagocyte cells in the development of LPS-induced ALI/Acute respiratory distress syndrome (ARDS) and described the relations between the dynamic phenotypic changes and pulmonary pathological evolution. In this study, mice were divided into two groups and intraperitoneally injected with normal saline (NS) or LPS, respectively. A series of flow cytometry assay was performed for the quantification of peripheral circulating monocyte subpopulations, detection of the polarization state of bronchoalveolar lavage fluid (BALF)-isolated alveolar macrophages (AMϕ) and pulmonary interstitial macrophages (IMϕ) separated from lung tissues. Circulating Ly6C lo monocytes expanded rapidly after the LPS challenge on day 1 and then decreased to day 7, while Ly6C hi monocytes gradually increased and returned to normal level on the 7th day. Furthermore, the expansion of M2-like AMϕ (CD64 + CD206 + ) was peaked on day 1 and remained high on the third day, while the polarization state of IMϕ (CD64 + CD11b + ) was not influenced by the LPS challenge at all the time points. Taken together, our findings show that Ly6C lo monocytes and M2-like AMϕ form the major peripheral circulation and pulmonary immune cell populations, respectively. The dynamic changes of mononuclear phagocyte in three compartments after the LPS challenge may provide novel protective strategies for mononuclear phagocytes.

【 授权许可】

CC BY