Magnetic targeted delivery of the SPIONs-labeled mesenchymal stem cells derived from human Wharton's jelly in Alzheimer's rat models.

Alzheimer's disease (AD) as a progressive neurodegenerative disorder is one of the leading causes of death globally. Among all treatment approaches, mesenchymal stem cells (MSCs)-based therapy is a promising modality for neurological disorders including the AD. This study aimed to magnetically deliver human Wharton's jelly-derived MSCs (WJ-MSCs) toward the hippocampal area within the AD rat's brain and determine the effects of them in cognitive improvement. Rats were randomly divided into five groups as follow: vehicle-treated control, AD model (injection of 8 μg/kg of amyloid β 1-42), IV-NTC (treated with IV-injected Non-Targeted Cells), IV-TC (treated with IV-injected Targeted Cells), and ICV-NTC (treated with Intracerebroventricular-injected Non-Targeted Cells). WJ-MSCs were labeled with dextran-coated superparamagnetic iron oxide nanoparticles (dex-SPIONs, 50 μg/ml), by bio-mimicry method. SPIONs-labeled MSCs were highly prussian blue positive with an intracellular iron concentration of 2.9 ± 0.08 pg/cell, which were successfully targeted into the hippocampus of AD rats by a halbach magnet array as magnetic targeted cell delivery (MTCD) technique. Presence of SPIONs-labeled cells in hippocampal area was proved by magnetic resonance imaging (MRI) in which signal intensity was reduced by increasing the number of these cells. Behavioral examinations showed that WJ-MSCs caused memory and cognitive improvement. Also, histological assessments showed functional improvement of hippocampal cells by expression of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE). Overall, this study indicates MTCD approach as an alternative in MSC-based regenerative medicine because it approximately has the same results as invasive directly ICV-injection method has.