Fig. 2.

Experimental setup, clinical features, imaging, and histology of EAE in treated and control animals. a) A confirmatory preclinical protocol, prospectively powered for clinical outcomes (see study design in material and methods), was carried out over 12 weeks. Six cynomolgus macaques were sensitised with rhMOG/IFA every four weeks (orange ticks), until the onset of EAE. Two groups of three macaques received treatment (green ticks) with anti-DC-ASGPR-MOG (T) or anti-DC-ASGPR-PSA(C) every week for three weeks after the initial immunisation and then every week after the boost with rhMOG/IFA. The onset of EAE was detected through clinical observation of the animals. Behavioural and neurological deficits were measured according to a grid that rates EAE severity (Supplemental table 2). b) Onset and progression of EAE in control animals (C1, C2, and C3) treated with anti-DC-ASGPR-PSA; higher scores reflect more severe illness. Blue stars (*) represent disease-associated brain lesions detected by MRI. c) Onset and progression of disease in animals treated with anti-DC-ASGPR-MOG. Green lines represent the basal scores of treated animals (T1, T2 and T3) and the black star represents an asymptomatic brain lesion detected by MRI. d) Volume of brain lesions detected by MRI in a control and two treated animals. e) Large hyperintense lesion imaged in animal C2 at 35 dpi, encircled by the dotted line. f) Small cortical lesion detected at 54 dpi in animal T2, encircled by the dotted line. From g-j): Brain histopathology of white matter lesions in control (g and h) and treated (i and j) animals, magnification 400×; (g and i) Haematoxylin Eosin (HE) staining; (h and j) Luxol-Fast-Blue-PAS (LFB) stain for myelin fibres. (g) Lesion of a control animal, showing severe myelin degeneration with the infiltration of numerous neutrophils (dark polymorphic nuclei) and a low number of activated microglia/macrophages (to the right of the black star). i) The lesion detected in one treated animal is infiltrated only by a few activated microglia/macrophages (black arrows). h) Severe ongoing myelin phagocytosis in a lesion of a control animal, as revealed by numerous LFB-positive granules in inflammatory cells (inset: magnification of the image, showing phagocytic cells with cytoplasmic vacuoles containing myelin). j) Demyelinated lesion in the treated animal with poor LFB staining and few LFB-positive granules in macrophages; (inset: normal LFB staining at the periphery of the lesion). During the course of this study, we performed many MRI acquisitions but most were normal. EAE in the control animals was severe, with a rapid evolution. The consecutive MRIs in one case (C1) were not informative concerning the progression of the lesions, which remained equally widespread for approximately one week. In the second animal (C2), MRI and the indication of euthanasia were quasi-concomitant, leaving little time to follow the lesions. Only the lesion detected in the one treated animal (T2) could be followed, but it disappeared two weeks after its first detection. Nonetheless, all acquisitions were analysed and processed, especially to assess the volume of the lesions, as reported. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)