cfMSC Stem Cell Therapy Targeting COPD

Inclusion Criteria: 1. Ability to understand the study protocol and the willingness to provide written informed consent; 2. Age 40-80 years old, male or female; 3. Diagnosed with moderate to severe COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines (GOLD Ⅱ-Ⅳ). 4. Regular use of COPD conventional drugs for more than 3 months, and the condition is stable for more than 4 weeks; 5. ineffective clinical treatment; 6. Life expectancy \> 6 months; 7. At least six months smoking cessation, including non-smoking during the treatment and follow-up periods of the study. Exclusion Criteria: 1. Combined with other serious lung diseases: asthma, active pulmonary tuberculosis, bronchiectasis, pulmonary embolism, interstitial lung disease, pulmonary hypertension, etc.; 2. A history of lung surgery (pneumonectomy, lung volume reduction surgery, etc.) or bronchial intervention surgery within 12 months; 3. Invasive or non-invasive mechanical ventilation history within 4 weeks, or moderate to severe acute exacerbation of COPD within 4 weeks; 4. Negative for HIV, HCV or syphilis serology; 5. A history of malignant tumors or malignant tumors under treatment; 6. Autoimmune diseases requiring long-term use of glucocorticoids or immunosuppressants; 7. Poorly controlled diabetes (fasting blood glucose \> 10.0 mmol/L) or severe metabolic diseases; 8. A history of alcohol or drug abuse, or mental diseases that cannot cooperate with the study; 9. Pregnancy or breastfeeding. 10. Unable or unwilling to comply with study specific schedules or procedures.