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bioRxiv · 10.1101/2022.02.08.479630

Multinuclear MRI reveals early efficacy of stem cell therapy in stroke

Abstract

Compromised adult human mesenchymal stem cells (hMSC) can impair cell therapy efficacy and further reverse ischemic recovery. However, in vitro assays require extended passage to characterize cells, limiting rapid assessment for therapeutic potency. Multinuclear magnetic resonance imaging and spectroscopy (MRI/S) provides near real-time feedback on disease progression and tissue recovery. Applied to ischemic stroke, 23Na MRI evaluates treatment efficacy within 24 h after middle cerebral artery occlusion, showing recovery of sodium homeostasis and lesion reduction in specimens treated with hMSC while 1H MRS identifies reduction in lactate levels. This combined metric was confirmed by evaluating treatment groups receiving healthy or compromised hMSC versus control (sham saline injection) over 21 d. Behavioral tests to assess functional recovery and cell analysis for immunomodulatory and macrophage activity to detect hMSC potency confirm MR findings. Clinically, these MR metrics may prove critical to early evaluations of therapeutic efficacy and overall stroke recovery.

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Helsper, S., Yuan, X., Bagdasarian, F. A., Athey, J., Li, Y., Borlongan, C. V., Grant, S. C.. 2022-02-10. Multinuclear MRI reveals early efficacy of stem cell therapy in stroke. https://doi.org/10.1101/2022.02.08.479630

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