FIG. 4.

Cellular localization of CXCL10/IP-10 RNA in the brain of GFAP-HIV gp120 transgenic mice. After in situ hybridization, some sections were further subjected to dual-label analysis to identify the cellular localization for CXCL10/IP-10 RNA expression. Immunostaining for GFAP (to label astrocytes) and neurofilament (NF; to label neurons) or binding of tomato lectin (to label microglia) was performed after in situ hybridization as described in Materials and Methods. Top panels, immunohistochemistry for wild-type animals. In the GFAP-HIV gp120 transgenic mice, numerous cells positive for CXCL10/IP-10 colabeled with the GFAP-positive cells (left panel, arrows). Few cells positive for the tomato lectin and representing the microglia were colabeled with CXCL10/IP-10 RNA expression (right panel, arrowhead). In contrast, no neurofilament-positive cells that were also positive for CXCL10/IP-10 were detected (middle panel).