Follow US Investment Immigration and US Technology: US scientists have confirmed for the first time that during the process of reprogramming mature cells to return to an embryonic-like state—a form of "rejuvenation"—physical properties can replace certain chemical compounds, significantly increasing the efficiency of this process. This new method is not only more controllable but also has fewer side effects.
In the experiment, bioengineers at the University of California, Berkeley, reprogrammed fibroblasts extracted from human skin and mouse ears on surfaces with parallel grooves 10 microns wide and 3 microns high. After cultivating these cells for several weeks in a "cocktail" specifically designed for cell reprogramming, they found that the new method resulted in five times as many "rejuvenated" fibroblasts compared to those cultivated on a smooth surface. The induced pluripotent stem cells obtained through this method can differentiate or develop into any cell in the body, holding significant value in the field of regenerative medicine.
British scientist John Gurdon and Japanese medical professor Shinya Yamanaka were awarded the 2012 Nobel Prize in Physiology or Medicine for their discovery that mature cells can be reprogrammed into immature cells, which can then develop into all tissues of the human body. Scientists believe that by reprogramming human cells, new methods for diagnosing and treating diseases can be developed.
However, in the current cell reprogramming process, scientists generally use a virus or chemical compound to introduce proteins that alter genes into mature cells. Timothy Downing, the lead author of the study and a graduate student in bioengineering at the University of California, Berkeley, said: "These methods are relatively inefficient, and certain forced genetic or chemical manipulations can have unpredictable effects. For example, valproic acid can significantly alter the epigenetic state of cells, but it can also lead to unexpected changes within the cells. Many people hope to find alternative ways to improve this reprogramming process."
Li Song, the lead researcher of the study and a professor of bioengineering at the university, stated: "Our research proves for the first time that the physical properties of biomaterials can replace certain biochemical factors; biophysical signals can be converted into chemical signals within cells, inducing cellular changes."
Previously, studies had proven that physical and mechanical factors affect cell fate, but their impact on the epigenetic state and cell reprogramming was unclear. The latest research found that cultivating cells on biomaterials with micro-groove patterns improves the quality of reprogramming and the number of "rejuvenated" cells, with efficiency comparable to that of valproic acid.
The researchers stated that they are currently investigating whether this method can eventually replace valproic acid or other compounds in cell reprogramming, and whether these biophysical factors can help in reprogramming cells into specific types (such as nerve cells, etc.).