Dissertation: Artificial oviduct for improved embryo production

Assisted reproduction is commonly used for the treatment of infertility and the production of both human and livestock embryos. Unfortunately, the current techniques used for this process (IVF, or ‘test tube fertilization’) do not take account of all of the factors involved in the natural fertilization process in mammals. Fertilization takes place in the oviduct, and is both more efficient than IVF and results in embryos with better characteristics for yielding healthy offspring. PhD Candidate Marcia Ferraz used 3D printing and nanofluidic perfusion technology to develop a 3D ‘oviduct-on-a-chip’ culture system. This system allows the observation of a variety of activation, fertilization and early developmental processes live under a microscope, something that cannot be achieved within the natural mammalian reproductive system. Further development of this artificial oviduct may both quantitatively and qualitatively improve embryo production in man and animals.

Ferraz grew oviduct epithelial cells on a porous membrane which allowed replication of a (blood) circulation under the epithelium, allowing recreation of the changes in hormone concentrations that occur just before and after normal ovulation. She was also able to introduce spermatozoa and egg cells onto the top of the epithelium, where they were activated by contact with the epithelium to undergo fertilization and embryo development.

For endangered domestic breeds and wild animal species threatened by extinction, the conditions required for successful artificial fertilization are unknown and can be challenging to determine. An artificial oviduct could provide a solution in these situations by offering a system able to support fertilization and early embryo development. Since September 2017, Marcia Ferraz has been conducting research at the Smithsonian Zoo in Washington D.C. to determine if the oviduct-on-a-chip system can be used for other (including endangered) mammalian species.