抄録
Bovine cumulus cells after oocyte maturation were cultured under serum-starvation condition or grown to confluence. Their cell size, cell cycle phases, and developmental potential as donors for nuclear transfer (NT) were investigated. The majority of trypsinized cells of both cultures were found within the medium size range (15-20 μm). Flow cytometric analysis revealed that small- and medium-sized cells had significantly higher percentages of nuclei existing in the G0/G1 phase (95-98%) than large-sized cells (82%) regardless of the culture conditions. Serum-starved cells of different sizes (small, 9-14 μm; medium, 15-20 μm; large, 21-26 μm) had the same fusion rate, cleavage, development to blastocysts, and blastocyst cell number of NT embryos. NT embryos reconstituted from serum-starved and confluent medium-sized cells showed the same developmental rate. These results indicate that the most available medium-sized cells derived from both serum-starvation and confluent cultures can be used as a G0/G1-phase nuclei source.
