Inclusion criteria of the test group: (1) Meeting the specific diagnostic criteria for related lung diseases; (2) The factors of lung diseases were infection and sepsis;~Inclusion criteria of the control group: control 1: (1) Meeting the specific diagnostic criteria for related lung diseases; (2) The factors of lung diseases were non-infectious factors.~Control 2: Healthy children~Exclusion criteria of the test group: (1) Patients with hemodynamic instability Patients with pulmonary hypertension;(2) Patients with congenital heart disease, congenital genetic metabolic disease, epilepsy, acute and chronic renal insufficiency, nephrotic syndrome, diabetes, et al.~The collection of clinical data includes: name, sex, age, hospitalization number, date of hospitalization, main diagnosis, course of disease, main examination and test results, medication, respiratory support, prognosis, etc.~Collect peripheral blood serum, sputum or alveolar lavage fluid samples for target sequencing.
Lung disease is the primary cause of hospitalization for children. For example, ARDS caused by severe lung infection is a serious clinical problem. The affected patients have serious clinical symptoms, and may have pulmonary complications such as lung consolidation and fibrosis, which will worsen the quality of life. Therefore, effective treatment is urgently needed. The exosomes derived from mesenchymal stem cells (MSC-Exo) has become a candidate treatment strategy for pulmonary inflammatory diseases through its immunomodulatory effect. In this study, we explored the role of MSC-Exo in children's lung diseases and determined the therapeutic mechanism of MSC-Exo. According to the inclusion and exclusion criteria, recruit subjects who meet the study, and then analyze their clinical data and blood, sputum or alveolar lavage fluid samples.