Ordinary Heart Cells Become 'Biological Pacemakers' With Injection of Single Gene

Source: Cedars-Sinai Medical Center

Date: December 16, 2012

Summary:

LOS ANGELES – Cedars-Sinai Heart Institute researchers have reprogrammed ordinary heart cells to become exact replicas of highly specialized pacemaker cells by injecting a single gene (Tbx18) – a major step forward in the decade-long search for a biological therapy to correct erratic and failing heartbeats.  The advance will be published in the Jan 8 issue of Nature Biotechnology and also will be available today on the journal’s website.

Cedars-Sinai researchers, employing a virus engineered to carry a single gene (Tbx18) that plays a key role in embryonic pacemaker cell development, directly reprogrammed heart muscle cells (cardiomyocytes) to specialized pacemaker cells. The new cells took on the distinctive features and function of native pacemaker cells, both in lab cell reprogramming and in guinea pig studies.

If subsequent research confirms and supports findings of the pacemaker cell studies, the researchers said they believe therapy might be administered by injecting Tbx18 into a patient’s heart or by creating pacemaker cells in the laboratory and transplanting them into the heart. But additional studies of safety and effectiveness must be conducted before human clinical trials could begin.

Salk Scientists Develop Faster, Safer Method for Producing Stem Cells

Source: Salk Institute for Biological Studies

Date: December 3, 2012

Summary:

LA JOLLA, CA—A new method for generating stem cells from mature cells promises to boost stem cell production in the laboratory, helping to remove a barrier to regenerative medicine therapies that would replace damaged or unhealthy body tissues.

The technique, developed by researchers at the Salk Institute for Biological Studies, allows for the unlimited production of stem cells and their derivatives as well as reduces production time by more than half, from nearly two months to two weeks.

They and their colleagues, including Fred H. Gage, professor in Salk's Laboratory of Genetics, have published a new method for converting cells in this week's Nature Methods.

Stem Cell-Derived Dopaminergic Neurons Rescue Motor Defects in Parkinsonian Monkeys

Source: Journal of Clinical Investigation

Date December 3, 2012

 Researchers have derived dopaminergic neurons from bone marrow stem cells in monkeys.

Parkinson's disease is a degenerative disorder of the central nervous system that is characterized by tremors, rigidity, slowness of movement, and difficulty walking. It is caused by loss of the neurons that produce the neurotransmitter dopamine (known as dopaminergic neurons). One of the primary goals in Parkinson's disease research is to develop a replacement for dopaminergic neurons.

In a new study, researchers led by Takuya Hayashi at the RIKEN Center for Molecular Imaging Science in Kobe, Japan, derived dopaminergic neurons from bone marrow stem cells in monkeys. The cells were retrieved during a standard bone marrow aspiration and then treated with growth factors that directed the stem cells to become dopaminergic neurons. The monkeys that donated the stem cells were treated with a chemical to induce Parkinson's disease and then received a transplant of the new dopaminergic neurons that had been derived from their own bone marrow stem cells. Monkeys that received the transplant showed significant improvement in motor defects.

This study demonstrates that dopaminergic neurons derived from adult bone marrow stem cells can be safely used to improve motor function in Parkinson's disease in monkeys.

The research is published in the Journal of Clinical Investigation.