Memories Of The Way They Used To Be
�A team of researchers from the University of California, San Diego School of Medicine and the Salk Institute for Biological Studies in La Jolla have developed a safe strategy for reprogramming cells to a pluripotent state without use of viral vectors or genomic insertions. Their studies reveal that these induced pluripotent stem cells (iPSCs) are very similar to human embryonic stem cells, yet maintain a “transcriptional signature.” In essence, these cells retain some memory of the donor cells they once were.
The study, led by UCSD Stem Cell Program researcher Alysson R. Muotri, assistant professor in the Departments of Pediatrics at UCSD and Rady Children’s Hospital and UCSD’s Department of Cellular and Molecular Medicine, will be published online in PLoS ONE on September 17.
“Working with neural stem cells, we discovered that a single factor can be used to re-program a human cell into a pluripotent state, one with the ability to differentiate into any type of cell in the body” said Muotri. Traditionally, a combination of four factors was used to create iPSCs, in a technology using viral vectors - viruses with the potential to affect the transcriptional profile of cells, sometimes inducing cell death or tumors.
In addition, while both mouse and human iPSCs have been shown to be similar to embryonic stem cells in terms of cell behavior, gene expression and their potential to differentiate into different types of cells, researchers had not achieved a comprehensive analysis to compare iPSCs and embryonic stem cells.
“One reason is that previous methodologies used to derive iPSCs weren’t ‘footprint free,’” Muotri explained. “Viruses could integrate into the genome of the cell, possibly affecting or disrupting genes.”
“In order to take full advantage of reprogramming, it is essential to develop methods to induce pluripotency in the absence of permanent changes in the genome,” added Fred H. Gage,psoriasis, PhD, a professor in the Laboratory for Genetics at the Salk Institute and the Vi and John Adler Chair for Research on Age-Related Neurodegenerative Diseases.
By creating iPSCs from human neural stem cells without the use of viruses, the scientists learned something new. While the genetic transcriptional profile of the new iPSCs was closer to that of embryonic stem cells than to human neural stem cells, the iPSCs still carried a transcriptional “signature” of the original neural cell.
“While most of the original genetic memory was erased when the cells were reprogrammed, some were retained,” said Muotri. He added that, in the past, it wasn’t known if this was caused by the use of viral vectors. “By using a footprint-free methodology, we have shown a safe way to generate human iPSCs for clinical purposes and basic research. We’ve also raised an interesting question about what, if any, effect the ‘memory retention’ of these cells might have.”
Additional contributors to the study include Gene W. Yeo, UCSD’s Department of Cellular and Molecular Medicine and the UCSD Stem Cell Program; Osamu Kainohana and Martin Marsala, UCSD Department of Anesthesiology; and Maria C. N. Marchetto and Fred H. Gage, the Salk Institute for Biological Studies, La Jolla, CA.
The research was supported by startup funds from the UCSD Stem Cell Research Program, and by grants from the California Institute of Regenerative Medicine and The Lookout Fund Foundation.
Source
University of California, San Diego Health Sciences
Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional. For more information, please read our terms and conditions.
Contact Our News Editors
For any corrections of factual information, or to contact the editors please use our feedback form.
Please send any medical news or health news press releases to:
Stem Cell Research
>
Categories A-B
Abortion
Acid Reflux / GERD
ADHD
Aid / Disasters
Alcohol / Addiction / Illegal Drugs
Allergy
Alternative Medicine
Alzheimer’s / Dementia
Anxiety / Stress
Arthritis / Rheumatology
Asbestos / Mesothelioma
Asthma Autism
Back Pain
Bio-terrorism / Terrorism
Biology / Biochemistry
Bipolar
Bird Flu / Avian Flu
Blood / Hematology
Body Aches
Bones / Orthopaedics
Breast Cancer
>
Categories C-D
Cancer / Oncology
Cardiovascular / Cardiology
Caregivers / Homecare
Cervical Cancer / HPV Vaccine
Cholesterol
CJD / vCJD / Mad Cow Disease
Cleft Palate
Clinical Trials / Drug Trials
Colorectal Cancer
Complementary Medicine
Compliance
Conferences
COPD
Cosmetic Medicine
Crohn’s
Cystic Fibrosis
Dentistry
Depression
Dermatology
Diabetes Dyslexia
>
Categories E-G
Ear, Nose and Throat
Eating Disorders
Eczema / Psoriasis
Endocrinology
Epilepsy
Erectile Dysfunction
Eye Health / Blindness
Fertility
Fibromyalgia
Flu / Cold / SARS
GastroIntestinal / Gastroenterology
Genetics Gout
Gynecology
>
Categories H-L
Headache / Migraine
Health Insurance / Medical Insurance
Hearing / Deafness
Heart Disease
HIV / AIDS
Huntingtons Disease
Hypertension
Immune System / Vaccines
Infectious Diseases
Irritable-Bowel Syndrome
IT / Internet / E-mail
Litigation
Liver Disease / Hepatitis
Lung Cancer
Lupus
Lymphology / Lymphedema
Lymphoma / Leukemia
>
Categories M-O
Medical Devices / Diagnostics
Medical Malpractice
Medical Practice Management
Medical Students / Training
Medicare / Medicaid / SCHIP
Melanoma / Skin Cancer
Men’s Health
Menopause
Mental Health
MRI / PET / Ultrasound
MRSA / Drug Resistance
Multiple Sclerosis
Muscular Dystrophy / ALS
Myeloma
Neurology / Neuroscience
Nursing / Midwifery
Nutrition / Diet
Obesity / Weight Loss / Fitness
Ovarian Cancer
>
Categories P-R
Pain / Anesthetics
Palliative Care / Hospice Care
Pancreatic Cancer
Parkinson’s Disease
Pediatrics / Children’s Health
Pharma / Biotech Industry
Pharmacy / Pharmacists
Plastic Surgery
Pregnancy / Obstetrics
Premature Ejaculation
Preventive Medicine
Primary Care / General Practice
Prostate / Prostate Cancer
Psychology / Psychiatry
Public Health
Radiology / Nuclear Medicine
Regulatory Affairs / Drug Approvals
Rehabilitation / Physical Therapy
Respiratory
>
Categories S-Z
Schizophrenia
Seniors / Aging
Sexual Health / STDs
Sleep / Sleep Disorders
Smoking / Quit Smoking
Sports Medicine / Fitness
Statins
Stem Cell Research
Stroke
Swine Flu
Transplants / Organ Donations
Tropical Diseases
Tuberculosis
Urology / Nephrology
Vascular
Veterans / Ex-Servicemen
Veterinary
Viruses / Bacteria
Water - Air Quality / Agriculture
Women’s Health
View full category list
Insomnia - What’s Keeping You Up at Night?
About a third of us will experience some bouts of insomnia in our lives, while 10 percent of the population will experience a chronic form of insomnia. Many things can cause insomnia - recognizing what’s keeping you up at night can help you fix the problem.
more videos are available in our health videos section.
swine flu nutrition cancer cardiovascular diabetes hiv obesity pediatrics neurology dermatology urology pregnancy psychology medicare infectious diseases alcohol breast cancer women’s health asthma gastrointestinal alzheimer’s stem cell research prostate bones pain sexual health smoking eye health sleep sports medicine multiple sclerosis health insurance medical devices hypertension dentistry biology genetics depression it arthritis autism pharma industry fertility abortion liver disease mrsa seniors nursing anxiety allergy
Recommend reading articles: