By Barbara and Stephen Byer Co-Directors, ALS WORLDWIDE

The first true stem cell was discovered and named in 1908 by the Russian scientist, Alexander Maksimov, who found that certain cells could generate blood cells. In 1963, Canadian researchers Earnest McCullough and James Till described the self-renewing nature of transplanted mouse mesenchymal cells. In 1998, Dr. James Thomson and his colleagues from the University of Wisconsin - Madison, announced the successful extraction of stem cells from human embryos in the laboratory. Enormous excitement surrounds these and related discoveries because stem cells have the potential to develop into many different cells, which means they can serve as an internal repair system. When a stem cell divides, it has the potential to either continue functioning as is or to become another type of cell with a more specialized function, such as muscle, red blood or brain cell. The most important characteristic of stem cells is their ability to renew, repair or replace worn out or damaged tissue.