Phase I Trial of QH-1A Hybrid Bio-Artificial Liver With Ex Vivo Blood-Purifying MSCs in Acute-on-Chronic Liver Failure

The goal of this Phase I clinical trial is to evaluate the safety and efficacy of combining the QH-1A bioartificial liver device with mesenchymal stem cells（MSCs） for blood purification in treating patients with acute-on-chronic liver failure, and to determine the optimal treatment duration and frequency for Phase II. The study will enroll patients aged 18 to 65 years who meet the diagnostic criteria for acute-on-chronic liver failure as outlined in the 2024 Chinese Liver Failure Clinical Guidelines. The main questions this study aims to answer are: * Does the combined therapy improve the 28-day survival rate after the final treatment? * Does the QH-1A device in its HBAL mode consistently achieve the predefined device performance pass rate? * Do patients show significant improvements in their biochemical markers following treatment? * What is the immunogenicity profile of the mesenchymal stem cells used for blood purification? Participants will be screened within 14 days before their first treatment and will be allocated into one of four groups based on treatment duration and frequency: * 4-hour group (3 patients) * 6-hour group (3 patients) * 8-hour group (3 patients) * Multiple-treatment group (6 patients) Treatment will be administered in a sequential escalation-from the 4-hour group up to the multiple-treatment group-based on safety data from a 28-day observation period, which will be reviewed by a Safety Evaluation Committee. In addition, upon referral to the Hepatitis B Health Clinic, participants will receive tailored health education, comprehensive liver function and virological assessments, and an individualized treatment and follow-up plan.