Figure 6. T cell motility in the leptomeninges during the development of EAE.

Leptomeningeal explants were prepared from MOG35-55 immunized mice harvested at various time points after immunization and imaged using confocal time-lapse microscopy directly ex vivo. The trajectories of individual CD4+ cells were calculated during a 1-hour time period and overlaid in two-dimensional plots, with each cell’s track originating at zero. The figures show trajectories for all migratory cells in each explant with the total number of CD4+ cells indicated. Multiple highly motile cells were identified in mice harvested before onset of clinical EAE on day 10–11 pi (A) and during the period immediately after peak of signs on day 17–18 pi (C), while few cells displayed a migratory behavior during peak of EAE on day 14–15 (B). (D) Percent motile CD4+ cells and (E) Instant velocities (μm/min) of migratory CD4+ cells (stationary cells excluded from analysis) in leptomeningeal explants harvested at different time points after immunization.