Longitudinal in vivo coherent anti-Stokes Raman scattering imaging of demyelination and remyelination in injured spinal cord

Abstract

In vivo imaging of white matter is important for the mechanistic understanding of demyelination and evaluation of remyelination therapies. Although white matter can be visualized by a strong coherent anti-Stokes Raman scattering (CARS) signal from axonal myelin, in vivo repetitive CARS imaging of the spinal cord remains a challenge due to complexities induced by the laminectomy surgery.We present a careful experimental design that enabled longitudinal CARS imaging of de- and remyelination at single axon level in live rats. In vivo CARS imaging of secretory phospholipase A2 inducedmyelin vesiculation, macrophage uptake ofmyelin debris, and spontaneous remyelination by Schwann cells are sequentially monitored over a 3 week period. Longitudinal visualization of de- and remyelination at a single axon level provides a novel platform for rational design of therapies aimed at promoting myelin plasticity and repair. © 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).