ABSTRACT
The pathological anatomical results of coronavirus disease-2019 (COVID-19) patients showed that excessive inflammatory reaction in the lungs is one of the important causes for such complications as acute lung injury or acute respiratory distress syndrome. Therefore, regulation of immune response may be an effective measure for COVID-19. Alveolar macrophages have a high heterogeneity and plasticity. The dynamic changes of subsets balance and function of M1/M2 alveolar macrophages have a significant effect on pulmonary inflammatory response during the early and late stages of infection. This paper reviews the classification and function of macrophages and explores the mechanism of alveolar macrophage in the pathological process of COVID-19 at different stages and the pharmacodynamic mechanism of traditional Chinese medicine. Besides, it provides ideas for the treatment of COVID-19 with traditional Chinese medicine and other drugs' research and development based on the regulation of macrophage polarization.