Lung Microbiome Participation in Local Immune Response Regulation in Respiratory Diseases

The lung microbiome composition has critical implications in the regulation of innate and adaptive immune responses. Next-generation sequencing techniques have revolutionized the understanding of pulmonary physiology and pathology. Currently, it is clear that the lung is not a sterile place; therefore, the investigation of the participation of the pulmonary microbiome in the presentation, severity, and prognosis of multiple pathologies, such as asthma, chronic obstructive pulmonary disease, and interstitial lung diseases, contributes to a better understanding of the pathophysiology. Dysregulation of microbiota components in the microbiome–host interaction is associated with multiple lung pathologies, severity, and prognosis, making microbiome study a useful tool for the identification of potential therapeutic strategies. This review integrates the findings regarding the activation and regulation of the innate and adaptive immune response pathways according to the microbiome, including microbial patterns that could be characteristic of certain diseases. Further studies are required to verify whether the microbial profile and its metabolites can be used as biomarkers of disease progression or poor prognosis and to identify new therapeutic targets that restore lung dysbiosis safely and effectively.