Exosomes in pulmonary infection: mediators of immune regulation and potential immunotherapeutic targets

Pulmonary infection is one of the major health problems worldwide, with common pathogens including viruses, bacteria, and fungi. During pulmonary infection, exosomes secreted by different immune cells serve as important communication mediators between cells and have the ability to regulate the immune system. Exosomes regulate lung immune responses by carrying bioactive molecules, including miRNA, proteins, and lipids, initiating and inhibiting inflammatory responses, pathogen clearance, and immune tolerance. This paper discusses multiple roles of exosomes in regulating the function of lung-resident innate immune cells (epithelial cells, macrophages, and neutrophils) and their potential effects in infectious diseases of the lung. In addition, the existing research has described the prospects of exosomes in immunotherapy. This review aims to summarise their role in the diagnosis and treatment of pulmonary infection in order to clarify the role and mechanism of exosomes in pulmonary infectious diseases.