title: Expression of Epithelial and Mesenchymal Differentiation Markers in the Early Human Gonadal Development.
abstract: Expressions of cytokeratin 8 (CK8), vimentin, nestin, and alpha-smooth-muscle-actin (alpha-SMA) were analyzed in the developing gonads of 12, 5-9 week old (W) human conceptuses by immunohistochemistry and immunofluorescence. During the investigated period, the number of CK8 positive cells increased from 56% to 92% in the gonadal surface epithelium, from 50% to 60% in the stroma, and from 23% to 42% in the medulla. In the early fetal period, the cell expression of CK8 increased in all gonadal parts, whereas primordial germ cells (PGC) remained negative. The expression of vimentin increased in the gonad stroma (gs) from 73% to 88%, and in the surface epithelium from 18% to 97% until ninth W. The medulla had the highest expression of vimentin in the seventh to eighth W (93%). Vimentin and CK8 colocalized in the somatic cells, while some PGCs showed vimentin expression only. Initially, nestin was positive in the gonad surface epithelium (8%) and stroma (52%), however during further development it decreased to 1% and 33%, respectively. In the early fetal period, the nestin positive cells decreased from 44% to 31% in the gonad medulla. Alpha-SMA was positive only in the blood vessels and mesonephros. The described pattern of expression of intermediate filaments (IF) in developing human gonads suggests their role in the control of PGC apoptosis, early differentiation of gs cells and cell migration. Both epithelial and mesenchymal origins of follicular cells and possible epithelial-to-mesenchymal transition of somatic cells is proposed. Lastly, IF intensity expression varies depending on the cell type and developmental period analyzed. Anat Rec, 300:1315-1326, 2017. © 2017 Wiley Periodicals, Inc.
authors.affiliation: Department of Pediatric Surgery, University Hospital Mostar, Bosnia and Herzegovina.
authors.forename: Vlatka
authors.initials: V
authors.lastname: Martinovic
authors.affiliation: Department of Gynecology, University Hospital Split, Croatia.
authors.forename: Tanja
authors.initials: T
authors.lastname: Vukusic Pusic
authors.affiliation: Faculty of Philosophy, University of Split, Croatia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Restovic
authors.affiliation: Faculty of Science, University of Split, Croatia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Bocina
authors.affiliation: Laboratory for Neurocardiology, Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Croatia.|Laboratory for Early Human Development, Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Croatia.
authors.forename: Natalija
authors.initials: N
authors.lastname: Filipovic
authors.affiliation: Laboratory for Early Human Development, Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Croatia.
authors.forename: Mirna
authors.initials: M
authors.lastname: Saraga-Babic
authors.affiliation: Laboratory for Early Human Development, Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Croatia.|Department of Histology and Embryology, School of Medicine, University of Mostar, Bosnia and Herzegovina.
authors.forename: Katarina
authors.initials: K
authors.lastname: Vukojevic
mesh_terms: D000943:Antigens, Differentiation / Q000378:metabolism*; D002454:Cell Differentiation; D004622:Embryo, Mammalian / Q000166:cytology* / Q000378:metabolism*; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D006066:Gonads / Q000196:embryology* / Q000378:metabolism*; D006801:Humans; D011247:Pregnancy
chemical_list: D000943:Antigens, Differentiation
keywords: EMT; embryo; gonad; human; intermediate filaments