Stem Cells by Parthenogenesis

Genetically matched pluripotent embryonic stem (ES) cells generated via nuclear transfer or parthenogenesis (pES cells) are a potential source of histocompatible cells and tissues for transplantation. After parthenogenetic activation of murine oocytes and interruption of meiosis I or II, we isolated and genotyped pES cells and characterized those that carried the full complement of major histocompatibility complex (MHC) antigens of the oocyte donor. Differentiated tissues from these pES cells engrafted in immunocompetent MHC-matched mouse recipients, demonstrating that selected pES cells can serve as a source of histocompatible tissues for transplantation. Parthenogenesis entails the development ofan embryo directly from an oocyte with-out fertilization. Many animal and plant species reproduce via parthenogenesis, but in mice, parthenogenetic embryos develop only to the early limb bud stage because mammalian embryonic development requires gene expres-sion from the paternal genome. Parthenogenetic embryonic stem (pES) cells have been isolated from parthenogenetic blastocysts of mice an