Reproduction Abstracts

The establishment of ES cells in domestic animals will help us to understand embryonic biology and improve the studies of regenerative medicine using stem cells. Among these domestic animal, pig can be particularly useful to study human diseases, because of similarities in size, immunology and physiology to human. In domestic animals including pig, however, authentic ES cells could not be derived from pre-implantation embryos. Although several attempts to establish ES cells have been tried from porcine pre-implantation embryos of the various stages (E6-E10), it could not derive the ES cells with characteristics shown in mES cells. Most of ungulate ES cell’s papers, including porcine ES cells, have shown similar characteristics to hES cells with monolayer colony morphologies, FGF culture condition and Activin/Nodal signaling pathways. Recently, we addressed the comparative study using ES-like cell lines derived from porcine embryos of various origins. Our results showed that stem cell lines derived from porcine pre-implantation embryos of various origins have a flattened morphology and FGF and Nodal/Activin signaling and belong to the category of EpiSC-like ES cells rather than authentic ES cells. It should be considered that defining the optimum stage of embryos for stem cell derivation is an important key to obtain stable ES cell lines with identifying optimum pluripotent markers and the key signaling pathways that regulate the pluripotency of ES cells in domestic animals. This work was supported by the BioGreen21 Program (PJ0094932013), RDA, Republic of Korea.