Fig. 1.

Clinical course, demyelination, infiltratory, axonal, and microglial status in the spinal cord of EAE animals. A Graphic depicts the EAE course and the two main time points analyzed. B % demyelination as resulted by LFB staining. On the chronic phase, demyelination was significantly lower compared to the acute phase (p < 0.01). Infiltratory burden (C) expressed as cells/mm² and axonal loss (D) measured semi-quantitatively (0 = normal/even silver stain throughout the white matter; 1 = small spurious areas in the white matter that lack silver stain; 2 = small, but frequent, areas in the white matter that lack silver stain; and 3 = extensive loss of silver stain throughout the white matter) were computed from the same sections of a modified Bielschowsky protocol counterstained with hematoxylin (panels F2, G2, H2, and their corresponding field magnifications F1, G1, and H1). Perivascular infiltrations were significantly higher in the acute phase compared to chronic (p < 0.01) while axonal loss was found higher in the chronic phase compared to acute (p < 0.05). Panels I2, J2, and K2 show the adjacent sections of the spinal cord stained for microglia/macrophages (Iba-1⁺; panels I1, J1, and K1 show corresponding field magnifications). Microglia (E, cells/mm2) differed significantly between control and EAE animals (p < 0.001 and p < 0.05 for acute and chronic phases, respectively). Error bars indicate the standard statistical error of the mean (SEM), #p < 0.001 (versus controls), **p < 0.01, *p < 0.05. Scale bar = 100 μm