Chronic Obstructive Pulmonary Disease (COPD) is a kind of chronic bronchitis or emphysema with characteristics of long-term poor airflow, resulting in chronic pulmonary heart disease, chronic respiratory failure or even death. Anatomically, the pulmonary bronchus structures in COPD patients are damaged and cannot be repaired by recent clinical treatment so far. This study intends to carry out an open, single-armed, phase I/II clinical trial to investigate whether bronchial basal cells can regenerate damaged lung tissue. During the treatment, bronchial basal cells will be isolated from patients' own bronchi and expanded in vitro. After careful characterization, cultured cells will be transplanted autologously into the lesion by fiberoptic bronchoscopy. The safety and efficacy of the treatment will be monitored by measuring the key clinical indicators.

Inclusion Criteria:

• Aged between 40 to 75;
• Diagnosed with COPD according the guideline (a. with symptoms of productive cough, sputum production or shortness of breath; b. with poor airflow as indicated by FEV1<70% predicted value and FEV1/FVC < 0.7 in pulmonary function test; c. with exclusion of other pulmonary disease by CT or blood examination.);
• Clinically stable for more than 4 weeks;
• Tolerant to bronchofiberscope;
• Written informed consent signed.

Exclusion Criteria:

• Pregnant or lactating women;
• Patients positive for syphilis, HIV;
• Patients with malignant tumor;
• Patients with serious significant pulmonary infection and need anti-infection treatment;
• Patients with serious heart disease(NYHA class Ⅲ-Ⅳ);
• Patients with a history of abusing alcohol and illicit drug;
• Patients participated in other clinical trials in the past 3 months;
• Patients assessed as inappropriate to participate in this clinical trial by investigator.