Figure 2

CCL18 localizes to scattered cells in the spinous layer of papilloma tissues and CCL20 localizes to the basal layer. CCL18 and CCL20 were detected by immunohistochemistry in papillomas and clinically normal adjacent epithelium of patients with severe RRP. (A) CCL1 8 stained scattered cells in the papillomas (thin arrow), but (B) showed only faint diffuse staining in normal adjacent tissues. (C) CCL20 was localized predominately to the basal layer of papillomas, adjacent to the basement membrane, while (D) normal adjacent tissue had uniform staining throughout the epithelium. (E,F) In situ hybridization, reprinted by permission from Steinberg, et al., 1988 (1), shows HPV-6/11 viral expression in the suprabasal layer. A–D scale bar = 20 µm; E and F scale bar = 100 µm; large arrows point to the basement membrane.