Stem Cells

Stem cells are the only cells in your body that make different cell types, like blood, bone and muscle cells. They also repair damaged tissue. Now, stem cells are essential blood cancer and blood disorder treatments. Medical researchers believe stem cells also have the potential to treat many other diseases.


What are stem cells?

If your body were a building, your stem cells would be the foundation. Stem cells are the only cells in your body that can create specialized cells. They can make more than 200 specialized cells, such as blood and bone cells, among the trillions of cells in your body. One stem cell type builds your body. After building your body, another stem cell type serves as maintenance crew teams assigned to specific structures.

Right now, healthcare providers use stem cells’ special qualities to treat blood cancer and blood disorders. Medical researchers are still learning how stem cells work and how stem cell therapies can treat or possibly cure diseases.


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How do stem cells function?

Stem cells do two things that no other cells can do:

  • They continuously renew and divide to make exact replicas of themselves. Typical or normal cells multiply and divide, but they have limited lifespans.
  • They’re the only cells that make specialized (differentiated) cells to replenish or repair specific cell types. Hematopoietic (pronounced “heh-ma-tuh-poy-EE-tik”) stem cells support blood and immune cells. Basal stem cells support skin cells. Mesenchymal (pronounced “mes-EN-ke-mul”) stem cells support bone, cartilage, muscle and fat.

Why are stem cells important?

Stem cells are important for the work they do to build and maintain your body. More than that, they’re essential to medical research. Researchers study stem cells to:

  • Understand how diseases happen. Researchers cultivate (grow) stem cells in various tissues and organs. Watching how stem cells change as they grow may help researchers to understand how diseases develop.
  • Learn how stem cells could replace damaged or unhealthy cells. Researchers are studying ways stem cells can become different kinds of cells that can treat damage or disease in specific parts of your body. For example, someday, researchers may make stem cells to treat severe burns by replacing damaged skin.
  • Test new treatments and medications. Researchers use stem cells to evaluate medications that may be more effective in treating specific diseases. By using specially prepared stem cells, researchers can determine if a treatment works and is safe before they give the drugs to people participating in clinical trials.

What are stem cell types?

Healthcare providers may classify stem cell types by the cells’ source or the cells’ function. Most people probably are more familiar with stem cell classification by source:

  • Embryonic (pluripotent) stem cells.These cells have the power to become any cell type. (“Pluri” means many. “Potent” comes from the Latin word for posse, or being powerful.) Medical researchers obtain embryonic stem cells from donated cord blood or embryos developed during in vitro fertilization.
  • Tissue-specific (multipotent or unipotent) stem cells.These cells can make new stem cells, but only for the tissue in which they live. For example, blood-forming stem cells in your bone marrow can make new blood cells and platelets. But they can’t make new lung or liver stem cells. Researchers obtain stem cells from donated tissue.
  • Induced pluripotent stem cells (iPS). These are lab-made stem cells that resemble and act like embryonic stem cells. Medical researchers use these cells to study how tissues develop and how disease affects tissue, and to test new drugs and treatments.

How do researchers work with stem cells?

The process starts with donated adult stem cells. Researchers grow millions of cells with the goal of turning the original adult stem cells into lab-made embryonic cells or pluripotent cells. (Lab-made embryonic cells are like natural embryonic cells, which can turn into any kind of cell.)


How do healthcare providers use stem cells to treat disease?

Providers may use adult stem cells to replace damaged or abnormal bone marrow stem cells. For example, stem cell transplants to replace stem cells in bone marrow may use donated adult stem cells. Providers use them to treat:

Do healthcare providers ever use embryonic stem cells?

Yes, providers may use stem cells from donated cord blood to treat blood disorders. (Cord blood is the blood that remains in people’s umbilical cords and placenta after they give birth.) Donated cord blood is the only embryonic stem cell treatment approved by the U.S. Food and Drug Administration (FDA).


Where do stem cells live in my body?

You have stem cells throughout your body, including your bone marrow, brain, blood vessels, skin and heart.


Conditions and Disorders

What common medical conditions affect stem cells?

Your bone marrow — the soft, squishy tissue at the center of some bones — makes stem cells that become blood cells and platelets. Red blood cells carry oxygen throughout your body. White blood cells help fight infection. Platelets manage bleeding. Anything that affects your bone marrow can affect those blood-forming stem cells. Common medical conditions that affect your stem cells include:


How can I keep my stem cells healthy?

There’s no proven way to create and maintain healthy stem cells, but following good healthy habits may help:

  • Eat a diet that combines lean protein, vegetables, fruit and whole grains.
  • Don’t smoke or use tobacco. Tobacco is a known carcinogen that damages cells and increases cancer risk.
  • If you drink beverages containing alcohol, limit how much you drink. The American Cancer Society guidelines state that people who choose to drink alcohol should limit their intake to no more than two drinks per day for men and one drink a day for women.
  • Protect your skin from ultraviolet light from the sun or tanning beds. Ultraviolet light is another known carcinogen.
  • Talk to your healthcare provider about vaccines to protect you from viruses.
  • Manage your stress. Stress takes a toll on your body. Activities such as exercise or meditation can help relieve stress.

Can I increase my number of stem cells naturally?

You may have read that taking certain vitamins may boost stem cell health or stem cell numbers. Researchers are studying the relationship between certain vitamins and stem cell health but haven’t concluded taking vitamins increase stem cell count.

A note from Cleveland Clinic

Your body contains trillions of cells. Stem cells stand out among the cellular crowd because they’re the only cell type that replicates itself indefinitely and creates specialized cells that can repair damaged cells. Right now, healthcare providers use stem cell treatments to manage and sometimes cure blood cancers and blood disorders. Medical researchers believe stem cells have the potential to treat and possibly cure many other serious illnesses.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 03/22/2023.

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