Cytokeratin-Positive Cells as Dendritic-Like Cells and Potential Albumin Coexpression in Follicles and CL

Abstract

Cytokeratin (CK)-positive follicle cells arise from the sex cords in bovine and human ovaries in the early fetal period. These cells disappear in preantral follicles and reappear in high numbers in preovulatory follicles and in CLs of early developmental stage. A few CK-positive cells are associated with the luteal microvascular bed. The microvascular CK-positive cell type seems to correspond with type 1 of among five different phenotype cultures derived from the bovine CL. Type 5 could compare with the steroidogenic CK-positive luteal cells after in vitro loss of CK expression. The following concept is put forward: During fetal time, the CK-positive cells seem imprinted with an immunological message relevant to later life. They might have a sentinel function, serving to recognize sites of danger and to respond to damage caused by acute and chronic inflammation with the aim of quickly restoring tissue integrity. Cytokeratin-positive cells are potential dendritic-like cells and thus ovary-specific executors of innate immunity function.