CHARACTERISTICS OF STEM CELLS : A BASIC EXPLANATION
Stem cells are the body’s repair team, much like a company’s IT department. If something isn’t working properly or is broken, you call the IT guys. During the good times, stem cells are at rest and are inactive.
As soon as a problem arises, they become active and start working. In particular, if you have an injury (skin injury, broken bone), they become active.
The technical service of a company is important for the maintenance of the company's infrastructure. Every company building is subject to wear over time. The same is true in the human body. Stem cells are needed for "maintenance work". In case of a skin injury from a cut or sunburn (UV light), the stem cells start e.g. to strengthen the partially damaged cells and to replace the completely damaged cells. Stem cells are therefore crucial for the renewal of the skin.
Unfortunately, there is not an endless supply of stem cells in all areas of the body, meaning that, in old age, the consequences of the ageing process become visible or healing/repairs are no longer successful. In such cases, we send cells from little-used or unused areas to the area where they are required because of advanced age or injury.
WHERE CAN STEM CELLS BE FOUND IN THE BODY?
Your skin is maintained and nourished by stem cells both within the skin (cutis) and outside the skin (subcutis). Stem cells used for renewing skin cells are found in the skin’s basal cell layer. The subcutis is located directly underneath the skin and contains the most important mesenchymal stem cells (MSCs). MSCs are in the subcutaneous fatty tissue, which is responsible for nourishing the skin. The term “mesenchymal” is derived from the Ancient Greek terms “mesos”, meaning “middle”, and “enkhuma”, meaning “infusion”. This term actually describes the location in the “middle” of the outer and inner skin (epithelium of the digestive tract). The “middle” is a very large area: When assessed considering both the terminology and cellular biology, it includes, for example, fatty tissue as well as bone and cartilage. Firstly, MSCs divide and then they form subcutaneous fatty tissue. This property is essential to protect and strengthen vital areas of skin. MSCs also form subcutaneous tissue which keeps the skin fresh and young.
WHEN ARE STEM CELLS REQUIRED?
Stem cells are not distributed evenly everywhere and are found in large numbers in some places (subcutaneous fatty tissue), whereas they are rather scarce in other areas, e.g., in delicate facial skin or joint cavities. Stem cells also do not divide all the time and not always at the same rate; rather, they wait for a reason to take action. In the meantime, they can be found in certain “waiting rooms” called niches. This is comparable to a fire station where the fire engines wait for a call. The difficulty for the body is informing the stem cells that they are needed and directing them to the correct place. The fire service can just be called out by calling 999, but it is not so easy to tell stem cells they are needed. In practice, most stem cells can only be activated from a nearby location, almost as if you were trying to call the fire service by shouting loudly from a nearby house. For example, many stem cells in fatty tissue are not aware that they might be needed in another part of the body.
This highlights the importance of transplanting a patient’s own stem cells. The doctor and patient can determine in consultations where the “fire” is in the patient’s body. Then, stem cells can be isolated from the fatty tissue and inserted in the right place where they are used for cell replacement and to support damaged cells.
WHAT IS THE EFFECT OF STEM CELLS?
- Anti-inflammatory characteristic:
Inflammation is the immune system’s defence reaction. Often, in an inflammatory reaction, part of the affected tissue is rejected. In cases of continuing inflammation, entire tissue can be destroyed, and this can even lead to organ failure. Inflammation must be recognised and brought under control at an early stage. Until now, inflammation has been treated using medication, e.g., anti-inflammatory medication. Mesenchymal stem cells, which are isolated from the body’s own fatty tissues, therefore provide the basis for a particularly successful form of therapy. The stem cells move to inflamed areas in the body and produce anti-inflammatory substances there (cytokine). This means that the body’s inflammatory response can be reduced, for example, in cases of wound healing and inflammatory signs of wear in the musculoskeletal system
- Regeneration (of cells):
Damaged tissue can only repair itself in certain circumstances.
Stem cells can develop into various types of tissue (muscle, cartilage, tendons, bones, nerves or fat cells), as well as reproduce and regenerate.