Therapeutic Efficacy of Co-administered WJ-MSCs and Exosomes in a Rat Pulmonary Fibrosis Model

BACKGROUND/AIM: . MATERIALS AND METHODS: gross morphological assessment, lung weight measurement, and histological analysis using Masson's trichrome staining to quantify the fibrotic area. RESULTS: Histological evaluation demonstrated significant fibrotic area expansion in the bleomycin group. While WJ-MSC or exosome monotherapies yielded minimal reduction in fibrotic burden, the combination therapy attenuated the fibrotic area by approximately 50% relative to the bleomycin-treated control, accompanied by a notable restoration of alveolar architecture. CONCLUSION: Co-administration of WJ-MSCs and their derived exosomes produced substantially greater anti-fibrotic effects than either treatment alone. These preliminary findings suggest exosomes prime the fibrotic microenvironment to enhance WJ-MSC engraftment, with additive paracrine contributions driving superior efficacy. As a single fixed dose at the upper range of previously validated doses was used due to limited animal numbers, future studies with dose-response designs, molecular marker analysis, and functional assessments are warranted.