Intracranial Inoculation Is More Potent Than Intranasal Inoculation for Inducing Optic Neuritis in the Mouse Hepatitis Virus-Induced Model of Multiple Sclerosis

Singh, Manmeet; Khan, Reas S.; Dine, Kimberly; Das Sarma, Jayasri; Shindler, Kenneth S.

Demyelinating optic neuritis induced by intracranial inoculation with RSA59 has been shown previously to lead to neuronal damage with loss of RGCs (Khan et al., 2014) . To examine whether intranasal infection with demyelinating strains of MHV FIGURE 1 | Comparative demyelination study between intracranially inoculated and intranasally infected mouse spinal cords. Serial thoracic (left column), cervical and lumbar (center and right columns) cross sections of spinal cord from post-inoculation day 26 intranasally mock-infected (A-C), RSA59-infected (D-F), and RSMHV2-infected (G-I) mice, and intracranially RSA59-inoculated mice (J-L) were stained with LFB (scale bar = 50 µm). Marked area indicate typical demyelinating plaques found in spinal cord white matter. Average demyelination score is 1.33 ± 0.2357; (mean ± SE) (M); n = 9/group; data comparisons were done by one-way ANOVA and Tukey's Multiple Comparison post-hoc testing with GraphPad Prism 6.0 software. ****p < 0.0001. results in neuronal loss, retinas were isolated from the same mice shown in Figure 1 , and RGCs were labeled and counted in a blinded fashion. Intracranially RSA59-infected mice had significantly fewer surviving RGCs compared to mock-infected mice, whereas mice infected intranasally with either RSA59 or RSMHV2 did not show RGC loss (Figure 3) .