The Changed Face of Skin Grafts

For many years, scientists have been harnessing  the regenerative capabilities  of human  skin to treat  victims of  severe  burns  using  skin  transplants.  Skin transplants are possible  because  of the existence  of stem cells located just under  the  top  layer of skin. Every day, thousands of new skin cells are produced to replace those that have been shed. When someone suffers severe burns  that  destroy  the source of these stem cells, their skin can no longer regenerate  on its own.   Traditionally, doctors  treated  severe burns  by ransplanting sections   of  skin   from   undamaged areas of the body onto  the burned  areas, but if doctors could not find enough  unharmed skin to cover the burned  areas, the patient  could die.  Now, scien- tists can grow  vast sheets of new skin by culturing the  stem  cells  from  small  pieces  of  healthy  skin. This practice,  which is a type of tissue engineering, has  become  routine  for  treating  burn  victims  over the
past  20  years.   Recently,  scientists  have  identi- fied  other  types  of  stem  cells in  hair  follicles and deeper layers of the skin. The inclusion of these new stem  cells into  engineered  skin  should  help  create more natural-looking skin transplants in the future.

Stem Cells Found in Umbilical Cord Blood

In 2005, the National Academies issued a report, Cord Blood: Establishing a National Hematopoietic Stem Cell Bank Program,  which recommended that a national  cord blood “bank” be established  to harness the medical  potential  of this source of stem cells. Such a bank would not only benefit the people from whom the blood was collected but anyone in need of blood transplants. As with blood banks for blood transfusions, scientists could screen the bank to find the best match for each patient, providing  a safer, more personalized living-cell therapy.