37 research outputs found
Stage-specific effects of the osmolarity of a culture medium on the development of parthenogenetic diploids in the pig
Influence of meiotic inhibition by butyrolactone-I during germinal vesicle stage on the ability of porcine oocytes to be activated by electric stimulation after nuclear maturation
Embryo development of porcine oocytes after injection with miniature pig sperm and their extracts
The role of cytoplasmic polyadenylation element sequence on mRNA abundance during porcine embryogenesis and parthenogenetic development
Induction and activation of meiosis and subsequent parthenogenetic development of growing pig oocytes using calcium ionophore A23187
Nonhuman primate parthenogenetic stem cells
Parthenogenesis is the biological phenomenon by which embryonic development is initiated without male contribution. Whereas parthenogenesis is a common mode of reproduction in lower organisms, the mammalian parthenote fails to produce a successful pregnancy. We herein describe in vitro parthenogenetic development of monkey (Macaca fascicularis) eggs to the blastocyst stage, and their use to create a pluripotent line of stem cells. These monkey stem cells (Cyno-1 cells) are positive for telomerase activity and are immunoreactive for alkaline phosphatase, octamer-binding transcription factor 4 (Oct-4), stage-specific embryonic antigen 4 (SSEA-4), tumor rejection antigen 1-60 (TRA 1-60), and tumor rejection antigen 1-81 (TRA 1-81) (traditional markers of human embryonic stem cells). They have a normal chromosome karyotype (40 + 2) and can be maintained in vitro in an undifferentiated state for extended periods of time. Cyno-1 cells can be differentiated in vitro into dopaminergic and serotonergic neurons, contractile cardiomyocyte-like cells, smooth muscle, ciliated epithelia, and adipocytes. When Cyno-1 cells were injected into severe combined immunodeficient mice, teratomas with derivatives from all three embryonic germ layers were obtained. When grown on fibronectin/laminin-coated plates and in neural progenitor medium, Cyno-1 cells assume a neural precursor phenotype (immunoreactive for nestin). However, these cells remain proliferative and express no functional ion channels. When transferred to differentiation conditions, the nestin-positive precursors assume neuronal and epithelial morphologies. Over time, these cells acquire electrophysiological characteristics of functional neurons (appearance of tetrodotoxin-sensitive, voltage-dependent sodium channels). These results suggest that stem cells derived from the parthenogenetically activated nonhuman primate egg provide a potential source for autologous cell therapy in the female and bypass the need for creating a competent embryo