FIGURE 10.

AQP4-negative stellate astrocytes. (A) An inactive hypercellular postphagocytic plaque (numerous lipid macrophages, no LFB-positive macrophages) stains negatively for AQP4. Large process-bearing AQP4-positive astrocytes are present in intact bordering white matter. Rare AQP4-positive large astrocytes and remnants of “original” GFAP-positive AQP4-positive astrocytes can be seen towards the edge of the plaque (arrows). (B) A greater magnification showing a preponderance of the numerous large astrocytes present are AQP4-negative gemistocytic astrocytes (there are 4 astrocytes in the field, one a stellate AQP4-positive astrocyte and 3 AQP4-negative gemistocytic astrocytes). (Case 14, AQP4, A: ×140; B: ×900.).