Figure 4.
Immunohistochemical detection of cellular proliferation (Ki-67) (A–C), and papillomavirus antigen (HPV E6) (D–F) in cervicovaginal tissues. (A) Normal animal, 20×. Ki-67+ proliferating cells are normally restricted to the basal cell layers of the ectocervix and vagina, as well as reserve cells beneath the endocervical mucosa (not shown). (B) Case 1: Cervical squamous metaplasia and dysplasia, 20×. Expanded cellular proliferation is seen throughout the epithelial layers. Arrow indicates large, bizarre nucleii of dysplastic keratinocytes. (C) Case 7: Anaplastic carcinoma, 20×. Occasional Ki-67+ proliferating cells are observed within the neoplasm. (D) Case 1: Cervical squamous metaplasia and dysplasia, 10×. Papillomavirus E6 oncoprotein is identified within the cytoplasm and nucleus of dysplastic keratinocytes. (E) Case 4: Suppurative cervicitis with dysplastic polyp, 10×. Papillomavirus E6 oncoprotein expressed within dysplastic epithelium of polyp. (F) Case 7: Anaplastic carcinoma, 20×. E6-positive cells are found in aggregates within the neoplasm. E6+ cells were also detected in the papillary carcinoma identified in a cotton top tamarin (data not shown).