September 2014 (No. 3)
Bovine oviductal epithelial cells: Long term culture characterization and impact of insulin on cell morphology
S. Palma-Vera*, R. Einspanier, J. Schoen
Freie Universität Berlin, Institute of Veterinary Biochemistry, Oertzenweg 19b, 14163 Berlin, Germany
In vitro models that resemble cell function in vivo are needed to understand oviduct physiology. This study aimed to assess cell functions and insulin effects on bovine oviductal epithelial cells (BOECs) cultured in an air–liquid interface. BOECs (n = 6) were grown in conditioned Ham’s F12, DMEM or Ham’s F12/DMEM with 10% fetal calf serum (FCS) for 3 weeks. After selecting the most suitable medium (Ham’s F12), increasing insulin concentrations (1 ng/mL, 20 ng/mL and 5 µg/mL) were applied, and cell morphology and trans-epithelial electrical resistance (TEER; n = 4) were evaluated after 3 and 6 weeks. Keratin immunohistochemistry and mRNA expres- sion of oviductal glycoprotein 1 (OVGP1) and progesterone receptor (PGR) were conducted (n = 4) to assess cell differentiation. BOECs grown without insulin supplementation or with 1 ng/mL of insulin displayed polarization and secretory activity. However, cells exhibited only 50% of the height of their in vivo counterparts. Cultures supplemented with 20 ng/mL insulin showed the highest quality, but the 5 µg/mL concentration induced massive growth. TEER correlated negatively with insulin concentration (r = ~0.459; p = 0.009). OVGP1 and PGR tran- scripts were still detectable after 3 and 6 weeks. Cellular localization of keratins closely resembled that of BOECs in vivo. Cultures showed heterogeneous expression of PGR and OVGP1 in response to estradiol (10 pg/mL). In summary, BOECs grown for long term in an air–liquid interface expressed markers of cell differentiation. Additionally, insulin supple- mentation (20 ng/mL) improved the cell morphology in vitro.
Reproductive Biology 2014 14 3: 206-212.
* Corresponding author: E-mail addresses: firstname.lastname@example.org, email@example.com