Exploring the Power of Stem Cells
While the study of many types of stem cells is still in its infancy, greater understanding of their capacity and of how to direct their activity could facilitate the development of new regenerative treatments for conditions such as Parkinson's disease, diabetes, spinal cord injuries, and cancer. "Embryonic stem cells are capable of giving rise to any type of tissue," explained Memorial Sloan-Kettering stem cell biologist Lorenz P. Studer. "They are the only cells that have such broad potential."
Memorial Sloan-Kettering created the Sloan-Kettering Institute stem cell research facility to explore the potential of these nascent cells. Center investigators are engaged in studies that range from learning how to manipulate them to repair damage caused by radiation treatment for brain tumors to the development of cell-based therapies targeting Parkinson's disease.
Support for the facility comes from The Starr Foundation, which, in 2005, made a $50 million gift to be distributed over three years to Memorial Sloan-Kettering, The Rockefeller University, and Weill Medical College of Cornell University to establish the Tri-Institutional Stem Cell Initiative. The Initiative includes basic and clinical stem cell research projects and places an emphasis on collaborative studies among the three institutions. It also supports graduate and postdoctoral training related to stem cell research and core research facilities to derive, maintain, and analyze human embryonic stem cells.
The Sloan-Kettering Institute stem cell research facility -- led by Dr. Studer, managed by Mark Tomishima, and staffed by two technicians -- will serve researchers from all three institutions. Its first task is to grow and maintain a large repository of stem cell lines, using human embryonic stem cells obtained from Weill Medical College of Cornell University, The Rockefeller University, and elsewhere.
This is no simple task, however, because by their very nature, "embryonic stem cells are extremely difficult to maintain," explained Dr. Tomishima. "They're inclined to differentiate into mature cells with specialized functions, but not usually the function you want them to have. Even for the best labs in the world, it can be a challenge. We're excited to contribute our expertise to help further this field." Sloan-Kettering Institute's stem cell facility staff will refine ways to coax embryonic stem cells to differentiate into specific types of cells -- such as nerve cells, bone, blood, or muscle -- for further study.
At various points during the process of generating embryonic stem cell lines, Memorial Sloan-Kettering scientists will test the cells to see whether they exhibit the properties that make them pluripotent embryonic stem cells. (A pluripotent cell is one that is able to develop into several different types of cells or tissues in the body.) This process is known as "characterization" and is a type of quality control in which the stem cells are checked to see if they contain specific protein markers that confirm they are undifferentiated cells -- meaning that they have not yet manufactured proteins characteristic of a specialized cell type -- and that they are genetically normal.
In addition, the stem cell core facility staff will provide training to scientists on how to grow human embryonic stem cells in their own laboratories. Consultation will also be available for researchers interested in working with embryonic stem cells from laboratory animals.
Once sufficient amounts of human embryonic stem cells have been produced, the staff will also be able to genetically modify them to mature into cells that overexpress or lack certain genes, providing useful models for studying the genetics of disease. For example, Dr. Studer has been able to introduce a gene into human embryonic stem cells that is frequently mutated in amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig's disease). When the stem cells differentiate into nerve cells -- called motor neurons -- they become sensitive to the gene's toxic effects, creating a model of ALS that can essentially be studied in a laboratory dish.
"The insights gained from our work will also be relevant to understanding cancer, because the signals that guide stem cells are in many cases closely related to those that drive cancer growth," concluded Dr. Studer.