Dead Mesenchymal Stem Cells for Radiation Lung Injury

Inclusion Criteria: * Received chest radiotherapy; * EOCG PS score of 0 to 3 points; * Diagnosis of radiation lung injury by the attending physician, grade 2 to 3 (according to the CTCAE v5.0 standards); * Main organs function is normal, that meet the following criteria: blood routine examination (within 7 days of unused hematopoietic growth factors and blood transfusion) : ANC ≥ 1.5 x 10\^9 / L, PLT ≥ 80 x 10\^9 / L, HGB ≥ 80 g/L;Biochemical examination: TBil ≤ 1.5 x ULN (upper limit of normal);ALT or AST ≤ 2.5 x ULN; Creatinine clearance ≥ 60 mL/min (Cockcroft - Gault formula); Blood coagulation function: INR or PT ≤ 1.5 x ULN, if the subjects are receiving anticoagulant therapy, as long as the scope of PT in anticoagulant drugs for it. Heart function examination, electrocardiogram (ECG) normal or abnormal ECG (by the researchers to determine the clinical significance). Heart doppler ultrasound assessment: LVEF ≥ 50%; * Radiation lung injury lasts less than 2 months； * Survival expectation ≥6 months; * Signed and dated written informed consent Exclusion Criteria: * Pregnant or lactating women, men and women of childbearing age who are unwilling or unable to take effective contraceptive measures; * People with a history of chronic bronchitis, emphysema, or cor pulmonale; * History of lung resection surgery; * Tumor progression; * People with severe lung infection; * Uncontrollable severe systemic diseases (e.g., central nervous system, cardiovascular system, blood system, digestive system, endocrine system, respiratory system, genitourinary system, immune system, etc.) and psychosis; * Serious cardiovascular events: a period of 6 months in heart failure (NYHA class III level IV), myocardial infarction, unstable angina, severe arrhythmia, cerebral infarction, cerebral hemorrhage; * Abnormal liver and kidney function: AST and ALT exceed the upper limit of normal by 2.5 times. Serum creatinine is greater than 1.5 mg/dl in men and 1.4 mg/dl in women; * Co-infection with HIV, Treponema pallidum, tuberculosis, influenza virus, adenovirus and other respiratory infections; * Hemorrhage or thrombosis, bleeding or anticoagulant drugs; * Combined with cachexia or other organ failure (requiring organ support); * Shock or invasive ventilation; * Combined with pulmonary interstitial pneumonia caused by other reasons or damage, or lung imaging showed radioactive lung injury diagnosed with pulmonary interstitial pneumonia or damage before; * Patients who have participated in clinical studies of stem cells; * The investigators believed that there were other reasons why participants were not suitable for the study.