2.7. Histological observation
Ears excised from mouse of each group were fixed with 4% paraformaldehyde for 16 h and embedded in paraffin. Paraffin embedded ears were sectioned into 6m thin sections and stained with hematoxylin (Sigma) and eosin (Sigma) (H&E). Infiltrated lymphocytes, thickening of the epidermis were observed under microscope and photographed.