Generation of embryonic stem-like cells from in vivo-derived porcine blastocysts at a low concentration of basic fibroblast growth factor.

Although basic fibroblast growth factor (bFGF) is an essential factor supporting the maintenance of porcine embryonic stem (ES) cell self-renewal and pluripotency, its high cost has limited previous studies, and the development of a low-cost culture system is required. For these systems, in vivo blastocysts were progressively cultured under various conditions consisting of different culture mediums and/or different feeder cell numbers at a low concentration of bFGF. As the results, the sequential culture of in vivo-derived porcine blastocysts on 5.0 × 105 mouse embryonic fibroblast (MEF) feeder cells in alpha minimum essential medium-based medium for primary culture, on 2.5 × 105 MEF feeder cells in Mixture medium for the 1st subpassage, and on 2.5 × 105 MEF feeder cells in DMEM/Ham's F10-based medium for the post-2nd subpassage could support the establishment and maintenance of porcine ES-like cells at the low concentration of bFGF. The established porcine ES-like cells showed ES cell-specific characteristics such as self-renewal and pluripotency. We confirmed that porcine ES-like cells could be generated from in vivo-derived porcine blastocysts at a low concentration of bFGF.