Figure 4

Optical nerve (ON) histopathology for the early infection group. a, b Representative Luxol Fast Blue-stained cross sections of ONs of an animal infected with E. coli (a) and an animal from the respective control group (b). Representative examples for the number of infiltrated ED1 macrophages/activated microglia detected in the ON of an E. coli infected animal (c) and an animal from the non-infected control group (d). e, f Bielschowsky’s silver impregnation of an ON cross-section revealed no differences in axonal densities in a MOG immunized animal infected on day 7 post immunization (e) compared to a non-infected respective control animal (f). j Represents the quantitative data for numbers of surviving retinal ganglion cells (RGCs) of the animals infected with E. coli and of the animals without infection. g, h and i represent the quantitative data for demyelination, inflammatory infiltrates and for axonal counts in both the E. coli infected and control group (n = 15 infected; n = 13 control). Bar length for Luxol Fast Blue, ED1, 100 µm, and for Bielschowsky’s silver impregnation = 20 µm.