Fig. 2

Immune cell infiltration and glial cell activation in the olfactory bulb during EAE. A–C Representative image with zoom-in (enlarged section displayed by frame in overview image) and quantification of A CD3⁺ cells infiltrating, (B) CD45⁺ macrophages and (C) Iba1⁺ microglia in the main olfactory bulb (coronar orientation) in healthy mice and at the acute phase of EAE (d15 p.i.) (n = 5 per group). Scale bar = 50 µm. D Localization of microglial activation measured by the ratio of microglial cell number per mm² in the lower caudal part of the olfactory bulb compared to the upper cranial part of the olfactory bulb in healthy mice and at the acute phase of EAE (n = 5 per group). E Representative images with zoom-in (enlarged section displayed by frame in overview image) and quantification per mm² of GFAP⁺ astrocytes in the olfactory bulb of healthy mice and at the acute phase of EAE (n = 5 per group). Scale bar = 50 µm. F UMAP plot showing the distribution of different immune cells infiltrating the olfactory bulb during the acute phase of EAE measured by flow cytometry (n = 12). G–P Quantification of immune cells isolated from olfactory bulbs at the onset of EAE (d9 p.i., n = 5) and at the acute phase of EAE (d15 p.i., n = 7) measured by flow cytometry. Shown are CD4⁺ T cells (G) and CD8⁺ T cells (H), CD19⁺ B cells (I), NK cells (J), NK-T cells (K), macrophages (L), polymorphonuclear neutrophiles = PMN (M), CD11b⁺ (N) and CD11b^– (O) conventional dendritic cells = cDC, plasmacytoid dendritic cells = pDC (P). Bars show mean values ± s.e.m. Statistical analysis was performed by Mann–Whitney U-Test; *P < 0.05, **P < 0.01