Figure 8.

Astroglia in confluent monocultures become elongated and reorganize to surround newly added meningeal fibroblasts or macrophages in a STAT3-dependent manner. A–C, Multicolor fluorescence imaging of immunostaining of GFAP and GS (A) or of GFAP (B, C) to visualize astroglia alone (A) in combination with red tomato-lectin binding (left) or CD45 immunostaining (right) for macrophages (Mφ; B) or fibronectin (Fibro) immunostaining for fibromeningeal cells (C) and Hoechst (Hoe) nuclear staining. A, Shows confluent monocultures of both control and STAT3-CKO astroglia. B, C, Shows cocultures at 2 d after macrophages (B) or fibromeningeal cells (C) have been added to confluent control or STAT3-CKO astroglia. Note that after addition of either cell type to control cultures (left), astroglia display elongated processes (arrows) that surround and enclose the added cells in circular structures. In contrast, STAT3-CKO astroglia (right) fail to form circular structures or surround the added cells, but instead the added cells intermingle among the astroglia (B, C). Scale bars: A–C, 50 μm.