Under the right conditions in the body or a laboratory, stem cells divide to form more cells called daughter cells. These daughter cells become either new stem cells or specialized cells (differentiation) with a more specific function, such as blood cells, brain cells, heart muscle cells or bone cells. No other cell in the body has the natural ability to generate new cell types.
Stem cells can be guided into becoming specific cells that can be used in people to regenerate and repair tissues that have been damaged or affected by disease.
People who might benefit from stem cell therapies include those with spinal cord injuries, type 1 diabetes, Parkinson's disease, amyotrophic lateral sclerosis, Alzheimer's disease, heart disease, stroke, burns, cancer and osteoarthritis.
Emerging evidence suggests that adult stem cells may be able to create various types of cells. For instance, bone marrow stem cells may be able to create bone or heart muscle cells.
This research has led to early-stage clinical trials to test usefulness and safety in people. For example, adult stem cells are currently being tested in people with neurological or heart disease.
Stem cells can make copies of themselves and turn into other types of cells. In adults, a small number of these unspecialized cells lie dormant in many organs and tissues. The idea that stem cells might be a source of renewable tissue for almost any part of the body is the basis for this line of treatments.
Mesenchymal stem cells (MSCs), which are found mainly in bone marrow and fat, are usually used for these procedures. The stem cells are separated from other tissue components and are then injected into your painful joint. The theory is that the stem cells will initiate tissue regeneration in the joint.
MSCs stimulate the production of anti-inflammatory proteins and growth factors. There is evidence - from studies of varying quality - that MSCs are safe and can improve pain and function in arthritic joints.