Researchers Identify First 'Universal' Stem Cell Marker; May Revolutionize Stem Cell Identification

[Jeremy]

Researchers Identify First 'Universal' Stem Cell Marker; May Revolutionize Stem Cell Identification


Story Filed: Thursday, August 30, 2001 5:00 PM EST

MEMPHIS, Tenn., Aug 30, 2001 /PRNewswire via COMTEX/ -- Researchers at St. Jude Children's Research Hospital have discovered what they believe to be the world's first "universal" stem cell marker. The scientists found that expression of the ABCG2/Bcrp1 gene plays a crucial role in identifying stem cells from a wide variety of sources.

The findings, published in the September issue of Nature Medicine, suggest that a recently discovered gene, ABCG2/Bcrp1, provides scientists with a much more accurate way of identifying true stem cells than has been available in the past. Researchers found that stem cells in the bone marrow, skeletal muscle and the early mouse embryo all expressed the ABCG2/Bcrp1 gene in a highly specific manner.

The research was conducted by a St. Jude team led by Brian Sorrentino, M.D., director of Experimental Hematology.

Sorrentino said that the remarkable part of this work is that stem cells from such diverse sources share expression of this single gene, while most mature cells showed no expression, underscoring the potential utility as a stem cell marker.

The discovery is particularly important because scientists around the world are racing to find new uses for stem cells -- undifferentiated cells that can produce a wide range of other specialized cells. Scientists suspect that stem cells may one day help them cure patients with Parkinson's and Alzheimer's diseases, strokes, heart attacks, liver disorders and spinal cord injuries. Because stem cells have the ability to develop into multiple cell types, they may eventually be used to restore function to damaged organs. They are currently used to treat people suffering from cancer, immune system disorders and genetic diseases.

Scientists have long been seeking an accurate method to identify stem cells. Many adult stem cells are found in the bone marrow. But in a sample of 100,000 bone marrow cells, only one or two may be stem cells. Scientists have been using several methods to identify the cells, including a common stem cell marker called CD34, but most cells identified with this method are not true stem cells.

"People have looked at a variety of other markers," Sorrentino said. "Nobody has ever found an absolutely specific stem cell marker. Our work suggests that ABCG2/Bcrp1 could be that type of marker."

In addition to identifying the new stem cell marker, the St. Jude scientists found that expression of the ABCG2/Bcrp1 gene may ensure that stem cells remain in a primitive state -- that they do not differentiate into red blood cells, white blood cells or other kinds of cells. This discovery might help scientists control stem cell differentiation.

The ABCG2/Bcrp1 research conducted at St. Jude involved animal stem cells. The scientists are currently working on a way to use the marker to identify stem cells from human bone marrow.

St. Jude Children's Research Hospital, in Memphis, Tennessee, was founded by the late entertainer Danny Thomas. The hospital is an internationally recognized biomedical research center dedicated to finding cures for catastrophic diseases of childhood. The hospital's work is supported through funds raised by the American Lebanese Syrian Associated Charities (ALSAC). ALSAC covers all costs not covered by insurance for medical treatment rendered at St. Jude Children's Research Hospital. Families without insurance are never asked to pay. For more information, please visit www.stjude.org.