Immunohistochemical detection of murine IP-10 in Matrigel plugs from C57BL/6 mice treated with or without anti–NK 1.1 monoclonal antibody treatment. Paraffin-embedded sections from Matrigel plugs alone (A); plugs impregnated with bFGF (B); plugs impregnated with bFGF + IL-12 (C); plugs impregnated with bFGF + monoclonal anti–NK 1.1 antibody (D); and plugs impregnated with bFGF + IL-12 + monoclonal anti–NK 1.1 antibody (E) were stained with a rabbit antimouse IP-10 antiserum and counterstained with hematoxylin. Some IP-10–positive cells (brown) are indicated by arrows. Original magnification ×40.