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bioRxiv · 10.1101/2025.05.24.655973

OPTRACE: Optical Imaging Guided Transplantation and Tracking of Cells in the Mouse Brain

Wang, J.·Russell, C.·Walczak, M.·Gao, D.·Qiao, G.·Fan, X.·Chu, C.·Janowski, M.·Walczak, P.·Liang, Y.
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Abstract

Intracerebral cell transplantation holds great promise for treating stroke and other neurological disorders, but progress is hindered by challenges in precise cell delivery and limited methods for monitoring post-engraftment dynamics. To address these limitations, we introduce OPTRACE (OPtical imaging-guided Transplantation and tRAcking of CElls), a two-step framework that integrates precision delivery with longitudinal in vivo tracking to advance cell therapy. During transplantation, OPTRACE enables real-time visualization using cost-effective translucent glass micropipettes, guided by predictive modeling to optimize delivery parameters. A novel pulse-elevation injection technique further enhances the precision of superficial cortical engraftment. Following transplantation, multicolor labeling combined with two-photon fluorescence microscopy permits longitudinal single-cell tracking, revealing host microglial responses, and altered neuronal calcium signaling at the graft interface. By unifying high-resolution delivery and tracking strategies, OPTRACE provides a powerful platform for elucidating engraftment biology and accelerating the development of effective cell-based interventions for neurological diseases.

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Wang, J., Russell, C., Walczak, M., Gao, D., Qiao, G., Fan, X., Chu, C., Janowski, M., Walczak, P., Liang, Y.. 2025-05-27. OPTRACE: Optical Imaging Guided Transplantation and Tracking of Cells in the Mouse Brain. https://doi.org/10.1101/2025.05.24.655973

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