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Vertebrate reproductive science and technology
RESEARCH ARTICLE

Equine oviduct explant culture: a basic model to decipher embryo–maternal communication

Hilde Nelis A F G , Katharina D’Herde B F , Karen Goossens C , Lynn Vandenberghe A , Bart Leemans A , Katrien Forier D E , Katrien Smits A , Kevin Braeckmans D E , Luc Peelman C and Ann Van Soom A
+ Author Affiliations
- Author Affiliations

A Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.

B Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, 9000 Ghent, Belgium.

C Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Heidestraat 19, 9820 Merelbeke, Belgium.

D Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.

E Center for Nano- and Biophotonics, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.

F These authors contributed equally to this work.

G Corresponding author. Email: hilde.nelis@ugent.be

Reproduction, Fertility and Development 26(7) 954-966 https://doi.org/10.1071/RD13089
Submitted: 14 March 2013  Accepted: 18 June 2013   Published: 1 August 2013

Abstract

Equine embryos remain for 6 days in the oviduct and thus there is a need for an in vitro model to study embryo–oviductal interactions in the horse, since this subtle way of communication is very difficult to analyse in vivo. Until now, no equine oviduct explant culture model has been characterised both morphologically and functionally. Therefore, we established a culture system for equine oviduct explants that maintained epithelial morphology during 6 days of culture, as revealed by light microscopy and transmission electron microscopy. We demonstrated the presence of highly differentiated, tall columnar, pseudostratified epithelium with basal nuclei, numerous nucleoli, secretory granules and apical cilia, which is very similar to the in vivo situation. Both epithelium and stromal cells originating from the lamina propria are represented in the explants. Moreover, at least 98% of the cells remained membrane intact and fewer than 2% of the cells were apoptotic after 6 days of culture. Although dark-cell degeneration, which is a hypoxia-related type of cell death, was observed in the centre of the explants, quantitative real-time PCR failed to detect upregulation of the hypoxia-related marker genes HIF1A, VEGFA, uPA, GLUT1 and PAI1. Since the explants remained morphologically and functionally intact and since the system is easy to set up, it appears to be an excellent tool for proteome, transcriptome and miRNome analysis in order to unravel embryo–maternal interactions in the horse.

Additional keywords: dark-cell degeneration, horse.


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