Safety of Umbilical Cord Mesenchymal Stem Cells (UC-MSC) in Patients With Decompensated Hepatitis B Cirrhosis

Inclusion Criteria: * 18 to 75 years old (including borderline values) at screening, regardless of gender * Diagnosed with decompensated hepatitis B cirrhosis according to the Guidelines for the Prevention and Treatment of Chronic Hepatitis B (2019 edition) * There's no significant reduction in cirrhotic symptoms or no significant improvement in quality of life score after more than 3 months of strict medical conservative treatment * HBV DNA ≤ 1000 IU/mL at the time of screening * Fully understand the informed consent form, voluntarily subject to the trial and sign the informed consent form. Exclusion Criteria: * other causes of cirrhosis, such as alcoholic hepatitis, viral hepatitis C, autoimmune hepatitis and metabolic-related fatty liver disease * Child-Pugh score \>12; * History of malignancy of the liver or other organs, or a family history of liver malignancy in three generations of immediate family members; * Current serious medical conditions that would affect your safety and treatment efficacy assessment as determined by the investigator, such as: Class II or higher abnormal cardiac function (NYHA criteria), cardiovascular disease such as ischemic heart disease (e.g., myocardial infarction or angina), poorly controlled diabetes (fasting glucose ≥ 10 mmol/L or glycated hemoglobin (HbA1c) ≥ 8%), serum creatinine \> 2 times the upper limit of normal (ULN), etc; * Recent uncontrolled gastrointestinal bleeding (e.g., severe bleeding tendency or active bleeding within 3…