Features | Partner Sites | Information | LinkXpress
Sign In
JIB
GLOBETECH PUBLISHING
GLOBETECH PUBLISHING

Induced Stem Cells Show Genetic Abnormalities Not Found in Embryonic Stem Cells

By BiotechDaily International staff writers
Posted on 15 Jul 2014
Image: Scanning electron micrograph of cultured human neuron from induced pluripotent stem cell (Photo courtesy of the University of California, San Diego).
Image: Scanning electron micrograph of cultured human neuron from induced pluripotent stem cell (Photo courtesy of the University of California, San Diego).
All stem cells are not created equal: genomic evaluation revealed that the genome of stem cells generated from adult cells (induced pluripotent stem cells or iPS cells) differed considerably from that of "gold standard" human embryonic stem cells (ES cells).

Human pluripotent stem cells hold potential for regenerative medicine, but available cell types have significant limitations. Although ES cells from in vitro fertilized embryos (IVF ES cells) represent the "gold standard," they are genetically distinct from likely transplant recipients, and their use is compromised by ethical and logistical considerations. While autologous iPS cells are freely obtainable, they are prone to epigenetic and transcriptional aberrations.

A team of researchers from the University of California, San Diego (USA), Oregon Health & Science University (Portland, USA) and the Salk Institute for Biological Studies (La Jolla, CA, USA) cooperated to perform a study to determine whether abnormalities found in iPS cells were intrinsic to somatic cell reprogramming or secondary to the reprogramming method. To this end, they prepared genetically matched sets of human IVF ES cells (four lines), iPS cells (seven lines), and two lines of nuclear transfer ES cells (NT ES cells) derived by somatic cell nuclear transfer (SCNT). The 13 cell lines were examined by genome-wide analyses.

Results published in the July 2, 2014, online edition of the journal Nature revealed critical differences in the genomes of stem cells created with the three methods. Specifically, DNA methylation and gene expression patterns in nuclear transfer ES cells more closely resembled those of ES cells than did iPS cells, which revealed alterations apparently caused by the reprogramming process.

“The nuclear transfer ES cells are much more similar to real ES cells than the iPS cells,” said co-senior author Dr. Louise Laurent, assistant professor of reproductive medicine at the University of California, San Diego. “They are more completely reprogrammed and have fewer alterations in gene expression and DNA methylation levels that are attributable to the reprogramming process itself. Our results have shown that widely used iPS cell reprogramming methods make cells that are similar to standard ES cells in broad strokes, but there are important differences when you look really closely. By using the egg cell to do the job, we can get much closer to the real thing. However, not only is nuclear transfer technically difficult, but federal funds cannot be used in experiments involving this procedure. If we can figure out what factors in the egg drive the reprogramming process, maybe we can design a better iPS cell reprogramming method.”

Related Links:

University of California, San Diego
Oregon Health & Science University
Salk Institute for Biological Studies



comments powered by Disqus

Channels

Drug Discovery

view channel
Image: Synthetic ion transporters can induce apoptosis by facilitating chloride anion transport into cells (Photo courtesy of the University of Texas, Austin).

Experimental Drug Kills Cancer Cells by Interfering with Their Ion Transport Mechanism

An experimental anticancer drug induces cells to enter a molecular pathway leading to apoptosis by skewing their ion transport systems to greatly favor the influx of chloride anions. To promote development... Read more

Therapeutics

view channel
Image: Liver cells regenerated in mice treated with a new drug (right) compared with a control group (center) after partial liver removal. Healthy liver cells are shown at left (Photo courtesy of Marshall et al, 2014, the Journal of Experimental Medicine).

New Drug Triggers Liver Regeneration After Surgery

Investigators have revealed that an innovative complement inhibitor decreases complement-mediated liver cell death, and actually stimulates postsurgery liver regrowth in mice. Liver cancer often results... Read more

Lab Technologies

view channel

Genome-Wide Mutation-Searching Computational Software Designed for Genomic Medicine

Analysis software cross-references a patient’s symptoms with his genome sequence to help physicians in the diagnosis of disease. This software was created by a team of scientists from A*STAR’s Genome Institute of Singapore (GIS), led by Dr. Pauline Ng. The research findings were published August 3, 2014, in the journal... Read more

Business

view channel

Partnership Established to Decode Bowel Disease

23andMe (Mountain View, CA,USA), a personal genetics company, is collaborating with Pfizer, Inc. (New York, NY, USA), in which the companies will seek to enroll 10,000 people with inflammatory bowel disease (IBD) in a research project designed to explore the genetic factors associated with the onset, progression, severity,... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.