Soft substrates may promote the production of induced pluripotent stem cells

May 02, 2014
Figure 1: Fluorescence microscopy image of cells cultured on soft (left) and rigid (right) substrates. Actin filaments (red) in these cells display dramatic differences in number and organization depending on substrate elasticity. Credit: The Society for Biotechnology, Japan

Converting adult cells into stem cells that can develop into other types of specialized cells is one of the most active areas of medical research, holding great promise for the treatment of disease and repair of damaged tissues. The techniques available for reprogramming adult cells into stem cells, however, remain imperfect and inefficient. In research that could help improve reprogramming efficiency, Sayaka Higuchi and colleagues from the RIKEN Quantitative Biology Center have now found that culturing cells on soft or elastic substrates enhances expression of some of the markers of stem cell reprogramming.

Motivated by previous observations that culturing cells on soft surfaces can affect their ability to multiply and renew, Higuchi and her team set out to examine whether the same principle might be applicable to enhancing the efficiency of producing induced pluripotent stem (iPS) cells—a type of stem cell that is reprogrammed from mature adult fibroblast cells using methods such as the introduction of genetic factors.

The researchers investigated the effect of culturing mouse and human fibroblasts treated with these factors on a range of gel substrates with different compositions and elasticities. They found that genes associated with reprogramming into stem cells were more active in the cells cultured on some of the soft surfaces than in the cells cultured on conventional rigid plastic dishes. They also found that changes in substrate elasticity significantly altered the amount and distribution of actin fibers, suggesting that the actin protein may be involved in mediating the effect of the substrate on the reprogramming process (Fig. 1).

Although the team did not proceed to the actual generation of viable stem cells, the results provide some promising avenues for further research. "It is likely that soft substrates promote only the initiation of the ," explains Higuchi. "Even so, the results could lead to more effective and reproducible ways to produce ."

Another possibility of particular interest to Higuchi follows from her team's observations that the combination of chemical treatment with substrate manipulation could potentially form the basis for a full reprogramming method that does not involve gene transfer—a process that involves retroviral infection of with pluripotency factors. "Gene transfer is still the main method for full reprogramming of iPS cells," says Higuchi, "but if we can find a method for producing pluripotent that avoids this process, the cells may be much safer for medical use."

Explore further: A protein required for integrity of induced pluripotent stem cells

More information: Higuchi, S., Watanabe, T. M., Kawauchi, K., Ichimura, T. & Fujita, H. "Culturing of mouse and human cells on soft substrates promote the expression of stem cell markers." Journal of Bioscience and Bioengineering 6, 749–755 (2014). DOI: 10.1016/j.jbiosc.2013.11.011

add to favorites email to friend print save as pdf

Related Stories

Embryonic stem cells: Reprogramming in early embryos

Mar 26, 2014

An Oregon Health & Science University scientist has been able to make embryonic stem cells from adult mouse body cells using the cytoplasm of two-cell embryos that were in the "interphase" stage of the cell ...

Recommended for you

Cohesin molecule safeguards cell division

12 hours ago

The cohesin molecule ensures the proper distribution of DNA during cell division. Scientists at the Research Institute of Molecular Pathology (IMP) in Vienna can now prove the concept of its carabiner-like ...

Nail stem cells prove more versatile than press ons

13 hours ago

There are plenty of body parts that don't grow back when you lose them. Nails are an exception, and a new study published in the Proceedings of the National Academy of Sciences (PNAS) reveals some of the r ...

Scientists develop 3-D model of regulator protein bax

15 hours ago

Scientists at Freie Universität Berlin, the University of Tubingen, and the Swiss Federal Institute of Technology in Zurich (ETH) provide a new 3D model of the protein Bax, a key regulator of cell death. When active, Bax ...

Researchers unwind the mysteries of the cellular clock

Nov 20, 2014

Human existence is basically circadian. Most of us wake in the morning, sleep in the evening, and eat in between. Body temperature, metabolism, and hormone levels all fluctuate throughout the day, and it ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.