Benign airway stenosis and respiratory tract fistula are common types of airway injury. The diseases occurred after endogenous and exogenous stimuli (tuberculosis, tumor, surgery, tracheal intubation) causing damage to the airway mucosa, resulting in scar repair and irreversible loss of airway epithelium. Autologous adipose vascular fraction (stromal vascular fraction, SVF) is a mixture of cells obtained from adipose tissue through digestion and centrifugation, containing a variety of cell types, such as mesenchymal cells, endothelial progenitor cells, endothelial cells, pericytes, and macrophages. Previous studies have shown that SVF can achieve regeneration and wound healing through modulating the immune microenvironment, promoting angiogenesis, thereby promoting endogenous regeneration of the in situ adult stem cells. This project utilizes the tissue repair function of autologous SVF to treat benign airway stenosis and respiratory tract fistula. To clarify the efficacy and safety of autologous SVF in the treatment of airway injury.

Inclusion Criteria:

• Subjects aged between 18 to 75
• Subjects diagnosed with benign airway stenosis, tracheoesophageal fistula(the sizes of the fistulas less than 2cm), and bronchopleural fistula
• Subjects willing to accept SVF treatment
• Subjects tolerant to the bronchoscope
• Subjects signed informed consent

Exclusion Criteria:

• Subjects with the following pulmonary diseases: asthma, active pulmonary tuberculosis, pulmonary embolism, pneumothorax, pulmonary hypertension, etc;
• Subjects with incomplete remission of malignant tumors or with incurable malignant tumors;
• Subjects with uncontrolled systemic infection;
• Subjects requiring anti-clotting drugs;
• Subjects with myocardial infarction, unstable angina, liver cirrhosis, acute glomerulonephritis, etc;
• Subjects with syphilis, HIV, HBV, HCV antibody positive;
• Subjects with Coagulation disorders such as hemophilia, giant platelet syndrome, thromboasthenia, etc;
• Subjects with severe renal damage, serum creatinine is more than 1.5 times the upper limit of the normal value;
• Subjects with liver disease or liver damage: ALT, AST, total bilirubin > 2 times the upper limit of the normal value;
• Subjects with a history of psychosis or suicide or epilepsy or other central nervous system diseases;
• Subjects with severe arrhythmias(e.g. ventricular tachycardia, frequent supraventricular tachycardia, atrial fibrillation, atrial flutter, etc.) or degree II above abnormal conduction;
• Subjects allergic to thrombin;
• Subjects accepted by any other clinical study within the first three months of the study;
• Subjects with poor compliance;
• Any other conditions might increase the risk of the patient or interfere with the clinical study.