Pilot Study of Human Adipose Tissue Derived Exosomes Promoting Wound Healing

After giving written informed consent, participants will be followed up once a week during the 2-week lead-in period to confirm that they meet the inclusion criteria.Patients who meet inclusion and exclusion criteria at the end of the induction period will receive treatment twice a week for 4 weeks or until recovery, whichever occurs first.When the observer confirmed that the wound had healed, the patient was followed up for two healing visits within the next 2 weeks.If the evaluator confirms target wound healing at the 4-week confirmatory follow-up, subjects will enter the study follow-up phase, which will be completed at 4 and 6 weeks after the end of the initiation phase.If the target wound did not heal after 6 weeks of treatment, participants completed follow-up at 4 and 6 weeks after the initiation period.

Inclusion criteria

• 1. Age from 18 to 60, regardless of gender; 2. Full-layer skin wounds on various parts of the body, lasting 4-8 weeks A. For post-amputation wounds, the time between operation and amputation must be more than 30 days; B. If there are wounds >1, select the largest wound as the research target; 3. At the beginning of the induction period, the wound size after debridement was ≥1 and ≤20 cm2; 4. Texas grade 1A, 1B, 1C, 1D, 2A, 2B, 2C or 2D; 5. Ankle-brachial index ≥0.7, including percutaneous oxygen pressure (TcPO2) ≥30 mm hg and skin perfusion pressure ≥30 mm hg; 6. No revascularization procedure or vascular surgery planned within the past or next 30 days; 7. The subject and their family members are willing and able to comply with all prescribed requirements for care and consultation; 8. Subjects have reasonable expectations of completing the study; 9. Subjects completed 2 weeks of initiation and wound reduction was 30%

Exclusion criteria

• 1. Signs of gangrene in any part of the torso and limbs of the subject; 2. Written diagnosis of osteomyelitis in any part of the affected limb; 3. Bone tissue at the wound site was exposed; 4. Poor blood glucose control: HbA1c>12% (108 mmol/mol); 5. Subject is receiving kidney dialysis or creatinine >2.5mg/ dL (221mmol/L); 6. The subject has obvious immune deficiency; 7. The subject has suspected tumor or is receiving tumor treatment; 8. Long-term use of steroids or immunosuppressants within the past 3 months or expected use during the study period; 9. During the screening period, subjects have received growth factor therapy, autologous platelet-rich plasma gel, bilayer cell therapy, dermal substitutes, extracellular matrix, etc.

• Subject participated in another research device, drug or biological trial within the past 30 days; 11. The wound showed severe symptoms of clinical infection, requiring hospitalization or immediate surgical treatment; 12. The subject has developed deep vein thrombosis within the past 30 days; 13. The subject is pregnant or breastfeeding; 14. The subject has serious mental illness and psychological abnormality; 15. The subject was determined by the attending physician to be unfit for this study.