Figure 2.

Curdlan-induced hyperacute EAE mice developed more severe demyelinating lesions with massive infiltration of T cells and neutrophils in the spinal cord. (A) We visualized myelin by Luxol fast blue stain (top panels) and infiltration of T cells and neutrophils by immunohistochemistry against CD3 (middle panels) and Ly-6G (bottom panels), respectively, in RR-EAE (left) and hyperacute EAE (right). In RR-EAE, we observed mild to moderate demyelination around perivascular spaces or subpial areas with infiltration of mononuclear cells (MNCs), mainly composed of CD3⁺ T cells; only a few neutrophils were observed in the meninges. In hyperacute EAE, we found severe demyelination with massive parenchymal infiltration of MNCs and polymorphonuclear cells (PMNs), which were composed of CD3⁺ T cells and Ly-6G neutrophils, respectively. In Luxol fast blue staining, arrowheads, paired arrows, and arrows indicate demyelination, perivascular cuffing (inflammation), and meningitis, respectively. In immunostaining, arrows indicate CD3⁺ T cells (middle panels) and Ly-6G⁺ neutrophils (bottom panels). Tissue sections are representative of five to eight mice per group. Scale bar = 50 μm. (B) Neuropathology scores of the spinal cords in RR-EAE (black bar) and hyperacute EAE (white bar). Hyperacute EAE mice had significantly higher pathology scores than RR-EAE in all pathology classes: demyelination, perivascular cuffing (inflammation), meningitis, and overall pathology. Values are the mean + standard error of the mean (SEM) of six to eight mice per group. **P < 0.01, Student’s t-test.