Morphologic and Immunohistochemical Features of the Cynomolgus Macaque Cervix

Abstract

Female macaques serve as an important model for the study of reproductive diseases in women. Here we summarize characteristics of the macaque cervix, with a particular emphasis on the cynomolgus macaque. Key anatomic features include a stratified squamous exocervix, squamocolumnar junction and transformation zone, and glandular endocervix with prominent colliculi. Endocervical eversion occurs with onset of ovarian cycling and regresses to varying degrees based on age, hormonal status, and individual conformation. The cervical epithelium in macaques is highly responsive to estrogens, which induce marked squamous epithelial maturation and glandular hypertrophy. Progestogen effects include further induction of endocervical secretory activity and release of viscous mucus, which functions in both mucosal immunity and fertility regulation. On immunohistochemistry, the squamous cervix shows strong expression of estrogen receptor α, the proliferation marker Ki67/MIB1, and cytokeratin 14, whereas endocervical epithelium strongly expresses estrogen and progesterone receptors and cytokeratins 18 and 19. These patterns of expression are altered in cervical intraepithelial neoplasia, which is a common spontaneous lesion of the macaque cervix associated with specific types of oncogenic papillomaviruses. This report highlights important similarities with human cervix that should be useful for future studies of genital infection, neoplasia, and immunity in the macaque model. Competing Interests: This article was sponsored by Covance Inc. and Schering-Plough. The author did not declare any other competing interests.