Walking, smiling and fidgeting, 3-year-old Dallas Hextell has become a poster child for the promise of stem cell therapy, a cutting-edge treatment approach that may one day heal diseases such as diabetes, brain injury and Parkinson's.
But he has also become a symbol, researchers say, of the worst side of experimental medicine: jumping to conclusions.
When Dallas was born, his parents, Derak and Cynthia Hextell, had arranged for a private blood bank to collect and store their son's umbilical cord blood on the remote chance that he or another family member might someday need it.
At 9 months, Dallas was diagnosed with cerebral palsy, a group of physical disorders related to brain injury around the time of birth. The Sacramento couple believe he improved dramatically after having an infusion of his own cord blood in July 2007 at Duke University, as part of a trial of several dozen children.
The grateful couple appeared with Dallas on NBC's "Today" show last March 11 to alert others to the lifesaving qualities of umbilical cord blood, and have started a foundation to raise awareness about cord blood banking. They are collaborating with a company to promote private banking.
But the story of one little boy has not yet changed the minds of major medical organizations. The American Academy of Pediatrics, the American Society for Blood and Marrow Transplantation and other groups do not recommend private cord blood banking, because there is little evidence that the expensive process will pay off for families -- even though the number of experimental therapies involving cord blood is growing.
"None of the therapies has shown to be ready for prime time or has been compared to any standard types of therapy," said Dr. Karen Ballen, an oncologist at Massachusetts General Hospital who helped write the guidelines for the blood and marrow transplantation organization.
Stem cell scientists say that the trial in which Dallas took part is very preliminary, and that until findings are published there is no way to know whether his gains had to do with the blood or whether he would have improved anyway.
Even the Duke scientist who treated Dallas says she is uncomfortable with the publicity his case has received and that it is too soon to judge the treatment.
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A broadening scope
Experiments with cord blood therapies are broadening in scope.
