Figure 5.

Micrographs of TNF-α positive cells in histological sections from spleen (A, C, and E) and lung (B, D, and F) of B16-C215 tumor-bearing TCR V_β3 TG mice. The immunoreaction is visualized by diaminobenzidine, giving a brown color at the site of reaction. A and B are from mice treated with the Fab–SEA D227A mutant, C and D are from mice treated with the Fab–SEA wild type, and E and F are from a control animal injected with PBS. In treated animals (B and D) TNF-α positive cells are seen dispersed among melanin-pigmented B16-C215 melanoma cells in the lung. TNF-α staining associated with dendritic-like cells are indicated by arrows. (Bars = 25 μm for A–F.)