Figure 2.

Antibody penetration into the skin. Goat IgG was applied on the shaved back and animals were sacrificed at the indicated times. Frozen sections were cut as 7um thick sections and fixed in methanol for 10 minutes and then rehydrated with PBS. After blocking with 3% H₂O₂ in rat serum, the sections were incubated with biotin labeled anti-goat IgG for 1h. The sections were incubated with streptavidin-HRP and then after washing with PBS were incubated with DAB for 10 min and then counter stained with hematoxylin and visualized under a light microscope. Goat IgG was applied on the skin and sections cut after various time intervals. Peroxidase staining with DAB was done as indicated in materials and methods. (i) control skin (ii) antibody applied skin after 15 min (iii) antibody applied skin after 2h (iv) antibody applied skin after 4h. There were two mice per group and each experiment was repeated twice with the same results.