Peritoneal Dysfunction

The goal of this clinical trial is to learn if a single intraperitoneal infusion of mesenchymal stem cell-derived exosomes (MSC-Exos) is safe and tolerable in adults with peritoneal dialysis-related peritoneal failure. It will also explore whether MSC-Exos might improve how well the peritoneum works (ultrafiltration and solute transfer). The main questions it aims to answer are: What is the highest single dose of MSC-Exos that can be given safely without causing unacceptable side effects? (This helps find the maximum tolerated dose and the dose to use in future phase II studies.) What medical problems (adverse events) do participants experience after receiving MSC-Exos? Does MSC-Exos show any early signs of improving ultrafiltration volume and solute transport across the peritoneum? Researchers will test increasing doses of MSC-Exos in small groups of participants. Each participant will receive one dose of MSC-Exos added to their usual 1.5% glucose dialysis solution (2 litres), which is then left in the abdominal cavity for 8 hours. The study does not use a placebo; instead, different dose levels are tested one after another to find the safest and most promising dose. Participants will: Receive a single intraperitoneal infusion of MSC-Exos through their dialysis catheter Be monitored closely before the infusion； Attend follow-up visits at 24 hours, 72 hours, 2 weeks, and 4 weeks after the dose; Have blood and peritoneal effluent samples taken at each visit to check for safety ; Have their ultrafiltration volume and solute transport ability measured at baseline and 4 weeks after the dose to see if any changes occur. All participants will be closely observed for any side effects. The results will help decide whether further studies are warranted.