Understanding and treatment of spinal cord pathology is limited in part by a lack of time-lapse in vivo imaging strategies at the cellular level. We developed a chronically implanted spinal chamber and surgical procedure suitable for time-lapse in vivo multiphoton microscopy of mouse spinal cord without the need for repeat surgical procedures. We routinely imaged mice repeatedly for more than 5 weeks postoperatively with up to ten separate imaging sessions and observed neither motor-function deficit nor neuropathology in the spinal cord as a result of chamber implantation. Using this chamber we quantified microglia and afferent axon dynamics after a laser-induced spinal cord lesion and observed massive microglia infiltration within 1 d along with a heterogeneous dieback of axon stumps. By enabling chronic imaging studies over timescales ranging from minutes to months, our method offers an ideal platform for understanding cellular dynamics in response to injury and therapeutic interventions.
At a glance
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- Supplementary Text and Figures (2M)
Supplementary Figures 1–5, Supplementary Notes 1–7, Supplementary Protocol
- Supplementary Video 1 (8M)
Rendering of MicroCT image data from a mouse taken 6 d after implantation of the imaging chamber, showing normal spine alignment and no vertebral damage.
- Supplementary Video 2 (8M)
Video of a mouse taken 2 weeks after implanting the imaging chamber, showing locomotion, grooming and exploratory behavior.
- Supplementary Video 3 (30M)
A series of 2PEF image stacks taken at different times after a laser-induced spinal cord injury, showing GFP-expressing axons (green) and Texas Red-dextran labeled vasculature (red).