Macrophage/microglial cells infiltrate the Purkinje cell layer after cell death has already begun.

<p>The Purkinje cell layer is shown at three points in time. Cells of macrophage/monocyte lineage were not detected within the Purkinje cell layer at 48 hours, or at 72 hours, when cell death was already apparent. Macrophage/mononuclear infiltration did not begin until 96 hours (data not shown) and was more extensive at 120 hours. These data indicate that initiation of Purkinje cell death did not involve antibody-mediated cellular cytotoxicity. Scale bar = 20μ.