P13 - Enfermedades humanas

Enhancing MSC-derived Extracellular Vesicle production with IMT504 for liver fibrosis therapy

Cantero, M. José ¹ - Casadei, Mailin ¹ - Bueloni, Barbara ¹ - Huamán Ormeño, Fátima ¹ - Lameroli, Lucía ¹ - Atorrasagasti, Catalina ¹ - Pacienza, Natalia - Bayo, Juan ¹ - Mazzolini, Guillermo ¹ - Fiore, Esteban ¹

1) Laboratorio de Hepatología experimental y Terapia Génica. Instituto de Investigaciones en Medicina Traslacional (IIMT), CONICET-Universidad Austral, Buenos Aires, Argentina
2) Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMeTTyB), Universidad Favaloro-CONICET, Buenos Aires, Argentina
Contacto: Canter.maj@gmail.com

Background: Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) are emerging as a promising platform for delivering therapeutic factors in regenerative medicine. Human umbilical cord perivascular cells (HUCPVCs) represent a valuable MSC source due to their accessibility, rapid proliferation, and low donor-to-donor variability. IMT504 is an oligodeoxynucleotide previously shown to stimulate MSC proliferation in bone marrow and mobilization into peripheral blood.

Aims: To evaluate whether pre-stimulation of HUCPVCs with IMT504 modulates EV production and to assess their therapeutic potential in experimental liver fibrosis. Methods: HUCPVCs from three independent donors were pre-treated or left untreated with IMT504 until passage 4. Cell proliferation (MTT assay) and migration (Boyden chamber) were assessed. Cell culture supernatants were collected after 48 h in FBS-deprived medium. EVs were isolated by ion-exchange chromatography and characterized for particle concentration and size distribution by Nanoparticle Tracking Analysis (NTA). 
Antifibrotic effects of EVs from IMT504-treated (EVs/IMT504) or control cells (EVs/Ctrl) were evaluated in a thioacetamide-induced liver fibrosis mouse model (200 mg TAA/kg, 3 doses/week). From week 6, EVs were injected intravenously every 5 days for 3 doses. At week 8, livers were collected and collagen deposition quantified by Sirius Red staining. Results: IMT504 pre-treatment enhanced HUCPVC proliferation and migration toward chemoattractant medium. EV yield from IMT504-treated cells was three-fold higher than in controls and exhibited a more heterogeneous size distribution. In vivo, treatment with either EVs/IMT504 or EVs/Ctrl similarly reduced collagen deposition in liver tissue, indicating that IMT504 pre-stimulation increases EV production without compromising their antifibrotic efficacy. Conclusion: Pre-stimulation of HUCPVCs with IMT504 enhances EV production while preserving their antifibrotic activity, representing a promising strategy to improve the scalability of EV-based therapies.

Palabras clave: MSCs-DERIVED EVs, IMT504, LIVER FIBROSIS