XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
 Surgery
 Aging
 Ophthalmology
 Gynaecology
 Neurosciences
 Pharmacology
 Cardiology
 Obstetrics
 Infectious Diseases
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
  Stem Cell Research
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
 
 India
Search

Last Updated: Nov 18, 2006 - 12:32:53 PM

Stem Cell Research Channel
subscribe to Stem Cell Research newsletter

Latest Research : Embryology : Stem Cell Research

   DISCUSS   |   EMAIL   |   PRINT
Neural stem cells derived from human embryonic stem cells carry abnormal gene expression
Aug 6, 2006 - 6:47:00 AM, Reviewed by: Dr. Priya Saxena

"This study is a very important first step in looking at the differentiation process in neural stem cells. Now we have a direct measurement of the types of cells that eventually, we hope, will be used for transplantation. We can tell, are they normal or not. Understanding why these cells under-expressed CPT 1A is the first step in a comprehensive understanding of cells obtained from human embryonic stem cells."

 
Neural stem cells grown from one of the federally approved human embryonic stem cell lines proved to be inferior to neural stem cells derived from fetal tissue donated for research, a UCLA study has found.

Researchers from the Institute for Stem Cell Biology and Medicine at UCLA coaxed cells from the federally approved line to differentiate into neural stem cells, a process that might one day be used to grow replacement cells to treat such debilitating diseases as Parkinson's and Alzheimer's. However, the neural stem cells expressed a lower level of a metabolic gene called CPT 1A, a condition that causes hypoglycemia in humans.

The study may shed new light on better ways to grow neural and other stem cells in the lab so they mirror normal cells and promote normal functioning, said Guoping Fan, an assistant professor of human genetics and a researcher in UCLA's stem cell institute. The study appears this week in an early online edition of the journal Human Molecular Genetics.

"This study is a very important first step in looking at the differentiation process in neural stem cells," said Fan, senior author of the study. "Now we have a direct measurement of the types of cells that eventually, we hope, will be used for transplantation. We can tell, are they normal or not. Understanding why these cells under-expressed CPT 1A is the first step in a comprehensive understanding of cells obtained from human embryonic stem cells."

The study, Fan said, deals with one of the most important aspects in stem cell biology - potential abnormalities in cells derived from human embryonic stem cells. Stem cells with abnormalities may not effectively treat the diseases they were created to treat, or they may result in secondary problems such as hypoglycemia, Fan said.

UCLA researchers also compared the neural stem cells they grew to cancer cells to ensure that the neural stem cells did not have any abnormalities in a DNA modification associated with gene silencing. The abnormal DNA modification is characteristically a hallmark of cancer cells. The good news, Fan said, is that the neural stem cells in their study did not share any abnormal characteristics associated with cancer. The means, theoretically, that a patient undergoing transplantation with these neural stem cells would not later develop a malignancy.

In the three-year study, researchers compared the neural stem cells grown in the lab from human embryonic stem cells to neural stem cells that already had differentiated and were derived from donated fetal tissue. The question: would the cell lines be the same and mirror the normal neural stem cells found in humans or would one cell line be superior to the other?

"Compared to the normal cells derived from the fetal tissue, the level of gene expression in the neural stem cells grown in the lab is lower," Fan said. "Proper levels of gene expression are essential for normal cell function. This study suggests that the differentiation procedure used in the lab needs to be improved so all genes are properly regulated in the stem cells we grow."

Fan and his colleagues now are studying what may have gone awry in the process they used to coax the human embryonic stem cells to differentiate into neural stem cells that may have resulted in the under-expression of the CPT 1A gene. They're also planning to repeat their work on other federally approved stem cell lines to see if the abnormality was an aberration found only in this one stem cell line. Fan and other UCLA researchers said the abnormality found in the federally approved stem cell line reinforces the need for other embryonic stem cells lines on which to conduct research.

To compare the neural stem cells, researchers extracted DNA fragments and used high throughput micro array technology to study the pattern of DNA cytosine methylation. They also monitored for levels of gene expression that are necessary for cell function as well as abnormalities that might be problematic.

"Any stem cells that might one day be used for transplantation have to be as close as possible to normal stem cells," Fan said. "The next step is to see if we can improve the way we grown these cells. I think we learned an important lesson with this study."
 

- The study appears this week in an early online edition of the journal Human Molecular Genetics
 

www.ucla.edu

 
Subscribe to Stem Cell Research Newsletter
E-mail Address:

 

The Institute for Stem Cell Biology and Medicine was launched in 2005 with a UCLA commitment of $20 million over five years. The ISCBM is committed to a multi-disciplinary, integrated collaboration of scientific, academic, and medical disciplines for the purpose of understanding adult and human embryonic stem cells. The institute supports innovation, excellence and the highest ethical standards focused on stem cell research with the intent of facilitating basic scientific inquiry directed towards future clinical applications to treat disease. The institute is a collaboration of the David Geffen School of Medicine, UCLA's Jonsson Cancer Center, the Henry Samueli School of Engineering and Applied Science and the UCLA College.

Related Stem Cell Research News

Neural stem cells derived from human embryonic stem cells carry abnormal gene expression
Neurons grown from embryonic stem cells restore function in paralyzed rats
New stem-cell findings can help the body to cure itself
Putting avian transgenics on a par with transgenic mice
Harvard to Create Human Embryonic Stem Cell Lines
Stem Cell Study for Patients with Heart Attack Damage Seeks to Regenerate Heart Muscle
Stem cells - An alternative to skin grafting?
Bone morphogenetic protein 6 (BMP-6) factor stimulates cartilage growth from stem cells
Doctors grow organ from patients' own cells
Stem cells can repair torn tendons or ligaments


For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us