DCs in Verruca vulgaris. Sections of Verruca vulgaris were obtained from a WHIM patient (A-D,F,H) and a control case (E,G) and stained for hematoxylin and eosin (A), HPV (brown, B), CD1a (blue in C; and brown D), CD207 (brown, C), BDCA2 (brown, E-F), and MxA (brown, G-H). Verruca vulgaris from WHIM patient 4 showed a moderate dermal mononuclear infiltrate (A) and contained HPV-infected keratinocytes (B). By immunohistochemistry, intraepidermal CD1a⁺CD207⁺ Langerhans cells (C) and dermal CD1a⁺ cells (D) were detected in WHIM patient biopsy. *Position of dermal papillae. Dermal BDCA2⁺ cells were detectable in control cases (E) but not seen in the patient biopsy (F). Strong reactivity for MxA was observed in keratinocytes from a control biopsy (G and inset), whereas it was completely negative in WHIM patient biopsy (H). Original magnifications are as follows: A,G-H, ×40 (scale bar represents 500 μm); B, ×600 (scale bar represents 20 μm); and C-F, inset in G, ×400 (scale bar represents 50 μm).