Posted on November 18, 2011
Nov 17, 2011
Cosmetic Surgery Times E-News
Paris — Researchers at Inserm, an arm of France’s health and research ministries, have successfully rejuvenated cells from elderly donors — some more than 100 years old — thus demonstrating the reversibility of the cellular aging process.
The institute is hailing the work as a significant step forward for regenerative medicine.
Since 2007, some scientists have been able to reprogram human adult cells into induced pluripotent stem cells (iPSC), which are similar in characteristics and potential to human embryonic stem cells (hESC). This kind of reprogramming makes it possible to re-form all human cell types without the ethical problems related to using embryonic stem cells. Previous research has shown senescence — the final stage of cellular aging — to be an obstacle to the use of this technique for therapeutic applications in elderly patients.
The Inserm team, led by researcher Jean-Marc Lemaitre, Ph.D., appears to have overcome this obstacle, according to an institute press release.
To achieve this, investigators used an adapted strategy that consisted of reprogramming cells using a specific “cocktail” of six genetic factors, two more than is usual. Researchers first multiplied fibroblasts from a 74-year-old donor to achieve the senescence that characterizes the end of cellular proliferation. Investigators then completed the in vitro reprogramming and found that the senescent cells, programmed into functional iPSC cells, reacquired the characteristics of embryonic pluripotent stem cells.
To check the cells’ rejuvenated characteristics, the team reversed the process. The rejuvenated iPSC cells were again differentiated to adult cells and compared to the original old cells, as well as to those obtained using human embryonic pluripotent stem cells.
Inserm quotes Dr. Lemaitre as saying, “Signs of aging were erased and the iPSCs obtained can produce functional cells, of any type, with an increased proliferation capacity and longevity. Our strategy worked on cells taken from donors in their 100s. The age of cells is definitely not a reprogramming barrier.
“This research paves the way for the therapeutic use of iPS, insofar as an ideal source of adult cells is provided, which are tolerated by the immune system and can repair organs or tissues in elderly patients.”
The study appears in the Nov. 1 issue of the journal Genes & Development.