Somatic nuclear transfer

Somatic nuclear transfer (SNT)—Mechanical transfer of the nucleus of a body cell to replace the nucleus of an animal or human egg. 

Booth PJ, Viuff D, Tan S, et al. Numerical chromosome errors in day 7 somatic nuclear transfer bovine blastocysts. Biol. Reprod. 2003 68(3) 922-928. 

McMahon Presumably the nuclear transfer experiments with somatic nuclei should give you some insight. 

Somatic cell nuclear transfer, species and cell types used for, 12 452t Somatic cells... 

Hlfoo Oocytes In the zygote up to midblastula transition Replaces somatic HI during somatic cell nuclear transfer RI ... 

Wakayama, T., V. Tabar, I. Rodriguez, A.C. Perry, L. Studer, and P. Mombaerts, Differentiation of embryonic stem cell lines generated from adult somatic cells by nuclear transfer. Science, 2001. 292(5517) 740-3. 

Over the past decade, significant progress has been made in stem cell research the derivation of ESCs from human blastocysts [9], the development of somatic cell nuclear transfer technology [10] and the confirmation that neurogenesis occurs in the adult... 

Wakayama, T. (2006). Establishment of nuclear transfer embryonic stem cell lines from adult somatic cells by nuclear transfer and its application. Ernst Sobering Res Found Workshop, 60, 111-23. 

Cloning of Dolly the sheep by somatic cell nuclear transfer (SCNT)... 

Human embryonic stem cells (hESCs) were first derived from the inner cell mass (ICM) from the blastocyst stage (-100-200 cells) of embryos generated by in vitro fertilization [35,36]. In humans the blastocyst is an early-stage embryo, approximately 4 to 5 days old. The blastocyst can be formed by means of either in vitro fertilization or somatic cell nuclear transfer, in which the nucleus of a somatic cell is combined with an enucleated oocyte. Methods have been developed to derive hESCs from the late morula stage (30-40 cells) and from arrested embryos (16-24 cells incapable of further development), and more recently from single blastomeres isolated from 8-cell embryos (37). 

As late as 1984, scientists David McGrath and Davor Solter wrote in the journal Science, The cloning of mammals by simple nuclear transfer is biologically impossible. That assertion has been proven false, and since that date sheep, mice, cows, monkeys—a virtual menagerie of mammals—have been cloned. A moratorium on the cloning of humans has been enforced by law and by intimidation. Yet the announcement of the first true human clone— from somatic cell and egg cell fusion to embryonic birth—is only a question of time. Whether it occurs in a federal laboratory or in a private clinic, it will happen. 

One concern with stem cell usage is that transplanted cells derived from stem cells can be tumori-genic owing to undifferentiated stem cells present in the population that proliferate uncontrollably.The use of stem cells, however, is promising because of the limited cell supply for many tissues. Cells that are not autogeneous must be able to avoid immune rejection. Somatic cell and nuclear transfer procedures could provide cells that function appropriately and... 

One approach to overcome the transplant rejection of human embryonic stem (ES) cells is to derive them by nuclear transfer of the patients own cells. In the absence of an efficient protocol for human somatic cell nuclear transfer (SCNT), several critical steps must be optimized, namely reprogramming time, activation method, and in vitro culture conditions. Reprogramming time was defined as the time between cell fusion and oocyte activation to permit proper embryonic development. A 2 h reprogramming time led to 25% of the recon-stracted embryos developing to blastocysts. In SCNT, in the absence of sperm-mediated activation, an artificial stimulus is needed to initiate embryo development. Addition of 10 pM ionophore for 5 min, and incubation with 2.0 mM 6-dimethyl aminopurine for 4 h, was the most efficient chemical activation protocol for human SCNT embryos. Encouragingly, inefficiencies in embryo culture have been overcome by supplementing... 

Human Somatic Cel Nuclear Transfer (SCNT) 273 Table 11.1 Conditions for human somatic cell nuclear transfer... 

Hwang Enudeation.mpeg Human somatic cell nuclear transfer (SCNT) enucleation, injection of donor cell and fusion donor cell and oocyte. (kindly provided by Woo Suk Hwang, Seoul National University)... 

Human platelet-derived growth factor, see PDGF Human protein processing 774 Human retinal pigment epithelial (hRPE) 325 Human serum albumin (HSA) 275 Human somatic cell nuclear transfer 273 Human tissue plasminogen activator... 

Somatic cell nuclear transfer, see SCNT Somatomedin-1 463 Somatonorm 477 Somatostatin receptor... 

Another quantum leap for modern biotechnology was the first cloned mammal by Ian Willmut in 1996 (see his quote for Modern Biopharmaceuticals ) by means of somatic cell nuclear transfer (SCNT) -the sheep Dolly . Then, in 2004, the first human embryo was cloned by a team led by Woo Suk Hwang, who was able to obtain pluripotent embryonic stem cells by SCNT of reprogrammed human adult cells. The highly differentiated genetic pro-... 

In 1997, Dolly the sheep was cloned by a technique called somatic cell nuclear transfer. A nucleus from an adult mammary cell was transferred into an egg from which the nucleus had been removed. The egg was allowed to divide several times In culture, then the embryo was transferred to a surrogate mother who gave birth to Dolly. Dolly died In 2003 after mating and giving birth herself to viable offspring. What does the creation of Dolly tell us about the potential of nuclear material derived from a fully differentiated adult cell Does the creation of Dolly tell us anything about the potential of an intact, fully differentiated adult cell Name three types of information that function to preserve cell type. Which of these types of Information was shown to be reversible by the Dolly experiment ... 

K. J. McCreath, J. Howcroft, K. H. S. Campbell, A. Colman, A. E. Schnieke and A. J. Kind, Production of gene-targeted sheep by nuclear transfer from cultured somatic cells. Nature, 405 (2000), 1066-1069. 

Irina A. Polejaeva, Shu-Hung Chen, Todd D. Vaught, Raymond L. Page, Mullins, Suyapa Ball, Yifan Dai, Jeremy Boone, Shawn Walker, David L. Ayares, Alan Colman and Keith H. S. Campbell, Cloned pigs produced by nuclear transfer from adult somatic cells. Nature, 407 (2000), 86-90. 

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