Developmental potential of bovine embryos reconstructed from enucleated matured oocytes fused with cultured somatic cells.

ABSTRACT

Muscle and skin biopsies taken from bovine fetuses and young calves have been used as a source of donor nuclei for cloning experiments. After culture, cells were individually fused to enucleated matured oocytes and the resulting blastocysts obtained after 7 d of culture (3-8% depending on the cell type) were transferred to foster recipient heifers. Two calves, a female and a male, both originating from muscle cells were born, and four additional pregnancies have surpassed mild-term gestation. The pregnancies include one fetus established from a transgenic nucleus from a fetal skin cell, and another one resulting from a skin biopsy performed on a female calf. Our data demonstrate that nuclei from cultured bovine somatic cells obtained from differentiated tissues can be made multipotent.