A recent article published in the Washington Post on September 30th announced astonishing news made by a group of Harvard Stem Cell Institute (HSCI) researchers. This important research published in Cell Stem Cell produced a new, safer method of obtaining human embryonic stem cells without having to destroy the embryos that they came from. This breakthrough method finds a way around the moral objections to human embryonic stem cell (hESC) research – That embryos must perish to yield up hESCs.
The new research, led by Derrick J. Rossi and his colleagues solves one of the major challenges facing the medical field in trying to use a patients own cells to treat their specific diseases.
In 2006, researchers discovered that they could coax human adult cells into a state that appeared identical to embryonic stem cells and then, just like embryonic stem cells, morph these ‘iPS cells’ into various tissues. But the problem with this process was that it involved inserting genes into cells using retroviruses, which raised the risk that these cells could cause cancer. Since then, scientists have been trying to develop safer methods. Several approaches using chemicals or other types of viruses have shown promise but none so far have eliminated the safety issues.
Dr. Rossi’s new approach involves molecules known as “messenger RNA” (mRNA), which cells use to create proteins they need to carry out vital functions. Working in the laboratory, the researchers created mRNA molecules carrying the instructions for the cell’s machinery to produce the key proteins needed to reprogram into iPS cells. Because the mRNA carries genetic instructions, but does not enter the DNA of the target cells, the resulting tailored cells are safer to use for treating patients.
According to Rossi: “Our findings address three major impediments to clinical translational use of iPS cells:
• The method: does not in any way breach genomic integrity as it does not necessitate integrating genes or viruses into the target cells’ DNA
• Is more efficient at producing iPS cells than conventional iPS methods, which were notoriously inefficient
• Gives us a way to directly program and direct the fate (development) of the iPS cells towards clinically useful cell types.”
This method avoids the ethical objection of destroying embryos and the iPS cells could in some ways, be superior to embryonic stem cells. For example, iPS cells allow scientists to take an easily obtainable skin cell from any patient and use it to create perfectly matched cells, tissue and potentially even entire organs for transplants that would be immune to rejection.
Rossi and his team used synthetic mRNA to reprogram adult human skin cells, fibroblasts, turning them into cells that are apparently identical to human embryonic stem cells, the initial building blocks of all the organs of the body. The researchers went one step further and showed that they could use this new method to quickly and easily convert the iPS cells they created into a specific cell types – like muscle tissue as an example.
As an added bonus, the research generated another finding – found a way to overcome the natural cellular immunity to the insertion of foreign RNA. Rossi says: “Although we developed this technology for cellular reprogramming, it actually has utility far beyond that. Basically our technology provides a means of transiently expressing any protein in a cell without eliciting the cell’s anti-viral response pathways. This could have potential therapeutic benefit in patients suffering from protein deficiencies.”
The important research work done by Dr. Rossi and his team was supported with funding from Derrick Rossi’s “startup package,” the money newly hired faculty receive from the Harvard Stem Cell Institute to establish their labs.
Read the entire article about the new cell reprogramming method
Hear Derrick Rossi describes his cell reprogramming breakthrough at a press conference