• Clinical-grade haMSC-EVs were manufactured with standardized quality control, demonstrating stability for up to 6 months at -80°C and suitable lot-to-lot consistency in miRNA and proteomic profiles.
• Intratracheal administration of haMSC-EVs at 1.5×10^8 particles/rat/day for 28 days showed no significant toxicity in rats, supporting their safety for preclinical use.
• In an LPS-induced ALI/ARDS rat model, intratracheal haMSC-EVs alleviated lung injury and reduced serum inflammatory factors, indicating therapeutic potential.
• The study provides a comprehensive framework for GLP-grade preclinical evaluation of nebulized allogenic MSC-EVs, advancing their translation as an off-the-shelf therapy for ARDS/ALI.