IVIg prevents CNS infiltration by T cells. (A) Histologic analysis of the cervical spinal cord of untreated (top) and IVIg-treated (bottom) mice stained with haematoxylin/eosin. Arrows indicate areas of spinal cord infiltrated by perivascular and subpial leukocyte aggregates. Left, 100×, right, 400× views of regions corresponding to boxed areas. (B) CNS cells isolated by percoll from 3 naive, IVIg-treated and -untreated mice were stained on day 27 after EAE induction and analyzed by FACS. Results are presented as percentage of Treg (▭) and Tconv () CD4⁺ T cells among the cells isolated from the CNS (mean of 3 mice). (C) Representative plots from individual mice, gated on CD4⁺.