Three-Dimensional Magnetic Bioprinting Spheroids as an In Vitro Model to Study the Oviductal Physiology.

In vitro models to study the oviduct are challenged by cellular dedifferentiation, a complex coculture system for embryo production, limited cell lifespan, and/or very complex methodologies. Hence, we aimed to develop an in vitro oviductal model using the magnetic bioprinting system, a three-dimensional (3D) culture system. Using the bovine epithelial and stromal oviductal cells (BOEC and BOSC, respectively), we produced the Oviductal Magnetic Spheroid (OMS), a duo somatic cell spheroid aggregate with self-organization capacity. The OMS showed to be viable for 21 days and recapitulated the oviductal tissue features after 7 days in culture, such as a simple epithelial cell layer facing outwards, expressing ciliation (acetylated tubulin positive) and secretory marker (oviduct-specific glycoprotein 1). Although the responsiveness for hormonal treatment with estradiol and progesterone in an estrous cycle-dependent way might require further improvements, the OMS offers an ethical and practical alternative as a three-dimensional oviductal in vitro model to study oviductal physiology, and maybe, a future platform to test therapies and a technology aiming to improve fertility and assisted reproduction success.