A study team headed by Dr. YANG Xiangzhong and TIAN Xiuchun, University of Connecticut, in collaboration with Dr. DUAN Enkui, Institute of Zoology, a part of the Chinese Academy of Sciences, harvested a stable embryonic stem cell line, through cloning a bovine embryo. Researchers said these cells could be repeatedly copied without a limit, or made into the cells of almost all bovine tissues or organs. The finding was published in the latest issue of journal Reproductive Biology.

Started from creating three embryonic stem cell lines, the study established one stem cell line using in-vitro impregnated embryos, and other two using transplanted embryos. Researchers used a very simple in-vitro technique. Egg cells were in-vitro impregnated into a tube fetus in a lab environment. Nucleid transplanting needs to denucleid unfertilized egg cells, before implanting DNAs of other cells.

Researchers observed that two nucleid transplanting lines had chromosomes similar to that of in-vitro line. The finding runs a bit different against same efforts reported in the past, namely some of chromosomes show negative. The specific marker expression of these stem cell lines bears a close resemblance to that of humans. The finding indicates that bovine embryonic stem cells, compared with that of mice, make a better simulating model for understanding human embryonic stem cells.