Figure 2.

Distribution of microglia and astrocytes in human brain metastases. The reaction of the microglia and astrocytes in human brain metastasis samples is comparable to the brain slice coculture system. A1–A3) Macrophage/microglia staining was performed employing the anti-KiM1P antibody. Activated macrophages/microglia accumulate in the adjacent brain tissue and at the interface. The majority of the activated macrophages/microglia infiltrate into the metastatic tissue. (B1–B3) Astrocyte response was demonstrated by GFAP IHC staining. Activated astrocytes accumulate in the adjacent brain tissue and form a barrier at the interface to the metastatic tissue. Furthermore, comparable to the brain slice coculture system, only few cells enter the tumor mass. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]