Efficient model for generating human iPSCs developed

Aug 01, 2013
This graphic depicts single RNA generation of human iPS cells. Credit: Peter Allen, UC Santa Barbara.

Researchers at the University of California, San Diego School of Medicine report a simple, easily reproducible RNA-based method of generating human induced pluripotent stem cells (iPSCs) in the August 1 edition of Cell Stem Cell. Their approach has broad applicability for the successful production of iPSCs for use in human stem cell studies and eventual cell therapies.

Partially funded by grants from the California Institute for Regenerative Medicine (CIRM) and the National Institutes of Health (NIH), the methods developed by the UC San Diego researchers dramatically improve upon existing DNA-based approaches – avoiding potential integration problems and providing what appears to be a safer and simpler method for future clinical applications.

The generation of iPSCs has opened the potential for regenerative medicine therapies based on patient-specific, personalized stem cells. Pluripotent means that these cells have the ability to give rise to any of the body's cell types. The human iPSCs are typically artificially derived from a non-pluripotent , such as a skin cell. They retain the characteristics of the body's natural , commonly known as . Because iPSCs are developed from a patient's own cells, it was first thought that treatment using them would avoid any immunogenic responses. However, depending on methods used to generate such iPSCs, they may pose significant risks that limit their use. For example, using viruses to alter the cell's genome could promote cancer in the .

Methods previously developed to generate integration-free iPSCs were not easily and efficiently reproducible. Therefore, the UC San Diego researchers focused their approach on developing a self-replicating, RNA-based method (one that doesn't integrate into the DNA) with the ability to be retained and degraded in a controlled fashion, and that would only need to be introduced once into the cell.

Using a Venezuelan equine virus (VEE) with structural proteins deleted, but non-structural proteins still present, the scientists added four reprogramming factors (OCT4, KLF4, SOX2 with either c-MYC or GLIS1). They made a single transfection of the VEE replicative form (RF) RNA into newborn or adult human fibroblasts, connective tissue cells that provide a structural framework for many other tissues.

"This resulted in efficient generation of iPSCs with all the hallmarks of ," said principal investigator Steven Dowdy, PhD, professor in the UC San Diego Department of Cellular & Molecular Medicine. "The method is highly reproducible, efficient, non-integrative – and it works."

Dowdy added that it worked on both young and old human cells. He explained that this is important since – in order to be used therapeutically in fighting disease or to create disease models for research – iPSCs will need to be derived from the cells of middle-aged to old adults who are more prone to the diseases scientists are attempting to treat. In addition, reprogramming factors can be easily changed.

Explore further: Take urine, add mouse cells and grow a new tooth

Related Stories

Induced pluripotent stem cells at risk for rejection

May 13, 2011

(PhysOrg.com) -- Biologists at UC San Diego have discovered that an important class of stem cells known as "induced pluripotent stem cells," or iPSCs, derived from an individual's own cells, could face immune ...

Take urine, add mouse cells and grow a new tooth

Jul 31, 2013

(Medical Xpress)—How to grow new teeth for people who are missing teeth because of old age, accidents, or disease has been an area of interest among researchers. Scientists in China say they have grown ...

Recommended for you

Fighting bacteria—with viruses

19 hours ago

Research published today in PLOS Pathogens reveals how viruses called bacteriophages destroy the bacterium Clostridium difficile (C. diff), which is becoming a serious problem in hospitals and healthcare institutes, due to its re ...

Atomic structure of key muscle component revealed

20 hours ago

Actin is the most abundant protein in the body, and when you look more closely at its fundamental role in life, it's easy to see why. It is the basis of most movement in the body, and all cells and components ...

Brand new technology detects probiotic organisms in food

Jul 23, 2014

In the food industr, ity is very important to ensure the quality and safety of products consumed by the population to improve their properties and reduce foodborne illness. Therefore, a team of Mexican researchers ...

Protein evolution follows a modular principle

Jul 23, 2014

Proteins impart shape and stability to cells, drive metabolic processes and transmit signals. To perform these manifold tasks, they fold into complex three-dimensional shapes. Scientists at the Max Planck ...

Report on viruses looks beyond disease

Jul 22, 2014

In contrast to their negative reputation as disease causing agents, some viruses can perform crucial biological and evolutionary functions that help to shape the world we live in today, according to a new report by the American ...

User comments : 0