Features | Partner Sites | Information | LinkXpress
Sign In
PZ HTL SA
GLOBETECH PUBLISHING LLC
GLOBETECH PUBLISHING LLC

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: The nano-cocoon drug delivery system is biocompatible, specifically targets cancer cells, can carry a large drug load, and releases the drugs very quickly once inside the cancer cell. Ligands on the surface of the \"cocoon\" trick cancer cells into consuming it. Enzymes (the “worms\" in this image) inside the cocoon are unleashed once inside the cell, destroying the cocoon and releasing anticancer drugs into the cell (Photo courtesy of Dr. Zhen Gu, North Carolina State University).

Novel Anticancer Drug Delivery System Utilizes DNA-Based Nanocapsules

A novel DNA-based drug delivery system minimizes damage to normal tissues by utilizing the acidic microenvironment inside cancer cells to trigger the directed release of the anticancer drug doxorubicin (DOX).... Read more

Lab Technologies

view channel

Experimental Physicists Find Clues into How Radiotherapy Kills Cancer Cells

A new discovery in experimental physics has implications for a better determination of the process in which radiotherapy destroys cancer cells. Dr. Jason Greenwood from Queen’s University Belfast (Ireland) Center for Plasma Physics collaborated with scientists from Italy and Spain on the work on electrons, and published... Read more

Business

view channel

Interest in Commercial Applications for Proteomics Continues to Grow

Increasing interest in the field of proteomics has led to a series of agreements between private proteomic companies and academic institutions as well as deals between pharmaceutical companies and novel proteomics innovator biotech companies. Proteomics is the study of the structure and function of proteins.... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.