Engineered neuron-targeting, placental mesenchymal stromal cell-derived extracellular vesicles for in utero treatment of myelomeningocele

Zhang, X.; Chen, H.; Gao, K.; He, S.; Ma, Z.; Liu, R.; Hao, D.; Wang, Y.; Kumar, P.; Ramasubramanian, L.; Pivetti, C. D.; Li, Y.; Guo, F.; Wang, F.; Carney, R.; Farmer, D. L.; Wang, A.

doi:10.1101/2021.09.22.461362

bioRxiv · 10.1101/2021.09.22.461362

Engineered neuron-targeting, placental mesenchymal stromal cell-derived extracellular vesicles for in utero treatment of myelomeningocele

Zhang, X.·Chen, H.·Gao, K.·He, S.·Ma, Z.·Liu, R.·Hao, D.·Wang, Y.·Kumar, P.·Ramasubramanian, L.·Pivetti, C. D.·Li, Y.·Guo, F.·Wang, F.·Carney, R.·Farmer, D. L.·Wang, A.

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Abstract

This study investigated the feasibility and efficiency of neuron-targeting hybrid placental mesenchymal stromal cell-derived extracellular vesicles (PMSC-EVs), engineered by membrane fusion with Targeted Axonal Import (TAxI) peptide modified, TrkB agonist 7,8-DHF-loaded liposomes for treatment of myelomeningocele (MMC) via intra-amniotic cavity administration. The prepared TAxI modified liposomes with 7,8-DHF were used to fuse with PMSC-EVs. Different fusion approaches were investigated and freeze-thaw-extrude method was found to be the optimal. The engineered PMSC-EVs had a uniform particle size and efficiently loaded 7,8-DHF. It also had typical markers of native EVs. Freeze-thaw-extrude process did not change the release profile of 7,8-DHF from engineered EVs compared to TAxI modified, 7,8-DHF loaded liposomes. The engineered EVs could elicit TrkB phosphorylation depending on the incorporation of 7,8-DHF while native EVs did not. The engineered EVs increased neurite outgrowth of apoptotic cortical neurons induced by staurosporine, suggesting that they exhibited neuroprotective function. In a rodent model of MMC, neuron-targeting, engineered EVs became an active targeting delivery system to MMC defect sites. Pups treated with engineered EVs had the lowest density of apoptotic cells and displayed a therapeutic outcome. The study suggests the potential use of engineered hybrid, active neuron-targeting EVs for the in utero treatment of MMC.

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Zhang, X., Chen, H., Gao, K., He, S., Ma, Z., Liu, R., Hao, D., Wang, Y., Kumar, P., Ramasubramanian, L., Pivetti, C. D., Li, Y., Guo, F., Wang, F., Carney, R., Farmer, D. L., Wang, A.. 2021-09-24. Engineered neuron-targeting, placental mesenchymal stromal cell-derived extracellular vesicles for in utero treatment of myelomeningocele. https://doi.org/10.1101/2021.09.22.461362

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