Summary of the three approaches.

<p>Summary of the three approaches.</p

Intact ON labelling approach is also feasible for GB filling of RGCs, with increased stability compared to ON cut approach.

<p>4A, B, and C represent ON cut approach with GB labelling at 7 days, 2 weeks and 3 weeks; 4 D, E, and F represent intact ON approach with GB labelling at 7 days, 2 weeks and 3 weeks, respectively. Scale bar represents 50 μm.</p

FG application onto the surface of ON could be taken up by intact ON fibers.

<p>5A: Cross section of FG labelled ON; 5B: Longitudinal section of FG labelled ON; 5C: Cross section of ON through sclera approach; 5D: Picture of sclera approach labelled retina. Scale bar represents 50 μm.</p

Decreased FG labeling without RGC loss at prolonged time points.

<p>A: FG labeling with intact ON approach at 7 days. B: IBA1 immunohistochemistry showing microglial cells. C: beta-tubulin immunohistochemistry showing all RGCs and axons. D: merged image of A and C. Arrows in C and D are showing RGCs without FG filling. Scale bar represents 50 μm.</p

Intact ON labelling approach leads to stable filling without subsequent RGC loss.

<p>3A, B, C, and D represent FG labelling of RGCs through ON cut approach at 2 days, 7 days, 2 weeks and 3 weeks. 3E, F, G, and H represent FG labelling of RGCs through intact ON approach at 2 days, 7 days, 2 weeks and 3 weeks, respectively. Arrows in C and D are showing residual RGCs that are with big soma size (potentially alpha-RGCs). Scale bar represents 50 μm.</p

RGCs numbers per mm² using different labelling methods.

<p>Note:</p><p>^# for non-significant.</p><p>* For P<0.05 in compared to SC labeling.</p><p>RGCs numbers per mm² using different labelling methods.</p

Intact ON labeling results in minimal injury to ON.

<p>7A, B: normal ON. 7C: 4 days after intact labeling. 7D: 7 days after intact labeling. Arrows in C and D indicate the myelin damage. Scale bar represents 10 μm.</p

Intact ON labelling approach results in the same quality of RGC filling with fluorescent dyes.

<p>2A: FG labelling of RGCs through superior colliculus application; 2B: FG labelling of RGCs through ON cut approach; 2C: FG labelling of RGCs through intact ON approach; 2D: GB labelling of RGCs through intact ON approach. Scale bar represents 20 μm.</p

Fluoro-Gold (FG) application onto the surface of the optic nerve (ON) is sufficient to label all RGCs at 2 days.

<p>1A: FG labelling of RGCs through superior colliculus application after 2 days; 1B: FG labelling of RGCs through ON cut approach after 2 days; 1C: FG labelling of RGCs through intact ON approach after 2 days; 1D: Granular Blue (GB) labelling of RGCs through intact ON approach after 2 days. Scale bar represents 100 μm.</p

Microglial cell density (cells/mm²) at 2, 7 and 14 days after experimental transection of the olfactory bulb in regions at zero µm, 200 µm and 400 µm from the injury site.

<p>Microglial cell density (cells/mm²) at 2, 7 and 14 days after experimental transection of the olfactory bulb in regions at zero µm, 200 µm and 400 µm from the injury site.</p