What are Stem Cells? by Dr. Donaldson

Everyone is talking about stem cells these days- but what are Stem Cells?

Stem cells have the remarkable potential to develop into many different cell types in the body during early life and growth. In many tissues they serve as a sort of internal repair system, dividing essentially without limit to replenish other cells as long as the person or animal is still alive.

When a stem cell divides, each new cell has the potential either to remain a stem cell or become another type of cell with a more specialized function, such as a muscle cell, a red blood cell, or a brain cell.

Stem cells are distinguished from other cell types by two important characteristics:

First, they are unspecialized cells capable of renewing themselves through cell division, sometimes after long periods of inactivity.

Second, under certain physiologic or experimental conditions, they can be induced to become tissue- or organ-specific cells with special functions.

In some organs, such as the gut and bone marrow, stem cells regularly divide to repair and replace worn out or damaged tissues. In other organs, however, such as the pancreas and the heart, stem cells only divide under special conditions.

Until recently, scientists primarily worked with two kinds of stem cells from animals and humans: embryonic stem cells and non-embryonic “somatic” or “adult” stem cells.

Scientists discovered ways to derive embryonic stem cells from early mouse embryos more than 30 years ago, in 1981. The detailed study of the biology of mouse stem cells led to the discovery, in 1998, of a method to derive stem cells from human embryos and grow the cells in the laboratory.

These cells are called human embryonic stem cells. The embryos used in these studies were created for reproductive purposes through invitro-fertilization procedures. When they were no longer needed for that purpose, they were donated for research with the informed consent of the donor.

Stem cells are important for living organisms for many reasons. In the 3- to 5-day-old embryo, called a blastocyst, the inner cells give rise to the entire body of the organism, including all of the many specialized cell types and organs such as the heart, lungs, skin, sperm, eggs and other tissues. In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacements for cells that are lost through normal wear and tear, injury, or disease.

There are several other cell-based therapies being developed to treat diseases- which is also referred to as regenerative medicine- given their unique regenerative abilities, stem cells offer new treatments for diseases such as diabetes and heart disease among several other diseases.

Call to schedule your consultation with Dr. Valerie Donaldson today- learn more about stem cell therapy by calling (412) 767-9890