Shining stem cells reveals how our skin is maintained

Aug 15, 2013
Previously, stem cells were thought to be organized in a strict hierarchy. In contrast, the new results show that the skin contains specialized stem cells holding a primary function, with the potential to change function if a need arises. This is illustrated in the figure, where the early stem cells were stained with a red protein a year before the pictures were taken. It shows that the stem cells maintain specialized functions as the skin develops and either forms the hair follicle, the fat gland or the barrier protecting us against environmental challenges. Credit: Kim Jensen, University of Copenhagen

All organs in our body rely on stem cells in order to maintain their function. The skin is our largest organ and forms a shield against the environment. New research results from BRIC, University of Copenhagen and Cambridge University, challenge current stem cell models and explains how the skin is maintained throughout life. The results have just been published in the recognized journal Cell Stem Cell.

New knowledge challenge stem cell models

The consists of many different cell types, including , fat- and . It protects us against microbial and chemical attacks and forms a waterproof barrier that prevents fluid loss. Associate professor Kim Jensen' group from BRIC have through mapping of stem cell's behaviour in the skin found out that the skin uses a unique method to renew itself. Their results challenge the current perception of how our skin is renewed.

"Until now, the belief was that the skin's were organized in a strict hierarchy with a primitive stem cell type at the top of the hierarchy, and that this cell gave rise to all other cell types of the skin. However, our results show that there are differentiated levels of stem cells and that it is their close micro-environment that determines whether they make hair follicles, fat- or sweat glands, says Kim Jensen.

The new research from Kim Jensen completes the stem cell puzzle.

"Our data completes what is already known about the skin and its maintenance. Researchers have until now tried to fit their results into the old model for skin maintenance.

However, the results give much more meaning when we relate them to the new model that our research proposes, says Kim Jensen.

One such example is that it explains the current mystery of how can divide too much and initiate a , without any traces of in the stem cells believed to maintain the outer layer of the skin. The research from the Jensen group may suggest that the reason that no changes can be found is, that these cells do not take part in the over-proliferation at all.

New knowledge of skin cancer and wound healing

Kim Jensen's research group has used a unique method based on new technology, to understand how the skin is maintained.

"We have marked the early skin stem cell with shining proteins in order to map stem cell behaviour in the outer layer of the skin. The stain is inherited by the daughter cells, so that we can trace their origin and make a family tree. The fine details of the family tree can be used to infer the stem cell's role in normal maintenance of the skin, as well as in wound healing, says Kim Jensen.

An important function of stem cells is to repair damaged tissue. Here, the results from the Jensen groups show that the different stem cell populations collaborate across their normal functions, to repair the skin as fast as possible. However, this can also cause harm, as these changes can "wake up" genes in the stem cells and give rise to cancer. The new results consequently also contribute with new knowledge on the origin of skin cancer.

"Our research will now take two directions. We will establish mathematical models for organ maintenance in order to "measure" what stem cells are doing in the skin. Also, we will expand our investigations in cancer initiation, hoping for results that can contribute to cancer diagnostics and improved treatment, says Kim Jensen.

Explore further: Researchers discover new strategy germs use to invade cells

More information: "The Epidermis Comprises Autonomous Compartments Maintained by Distinct Stem Cell Populations." Page et al Cell Stem Cell, advanced online publication on August 15, 2013.

add to favorites email to friend print save as pdf

Related Stories

Tracking nanodiamond-tagged stem cells

Aug 05, 2013

A method that is used to track the fate of a single stem cell within mouse lung tissue is reported in a study published online this week in Nature Nanotechnology. The method may offer insights into the factors that determ ...

Computational biology: Cells reprogrammed on the computer

Jul 31, 2013

Scientists at the Luxembourg Centre for Systems Biomedicine (LCSB) of the University of Luxembourg have developed a model that makes predictions from which differentiated cells – for instance skin cells – can be very ...

Ageing linked to cancer

Oct 08, 2012

Ageing is an unavoidable part of life, and it is often accompanied by a number of age-related illnesses. One of the biggest diseases associated with ageing is cancer, which as a result is often referred to ...

Recommended for you

Researchers discover new strategy germs use to invade cells

22 hours ago

The hospital germ Pseudomonas aeruginosa wraps itself into the membrane of human cells: A team led by Dr. Thorsten Eierhoff and Junior Professor Dr. Winfried Römer from the Institute of Biology II, members of the Cluster ...

Progress in the fight against harmful fungi

22 hours ago

A group of researchers at the Max F. Perutz Laboratories has created one of the three world's largest gene libraries for the Candida glabrata yeast, which is harmful to humans. Molecular analysis of the Candida ...

How steroid hormones enable plants to grow

Aug 19, 2014

Plants can adapt extremely quickly to changes in their environment. Hormones, chemical messengers that are activated in direct response to light and temperature stimuli help them achieve this. Plant steroid ...

Surviving the attack of killer microbes

Aug 19, 2014

The ability to find food and avoid predation dictates whether most organisms live to spread their genes to the next generation or die trying. But for some species of microbe, a unique virus changes the rules ...

Histones and the mystery of cell proliferation

Aug 19, 2014

Before cells divide, they create so much genetic material that it must be wound onto spools before the two new cells can split apart. These spools are actually proteins called histones, and they must multiply ...

User comments : 0