April 6, 2001 -- The umbilical cord has long symbolized the singular attachment of a fetus to its mother, and its severance and routine discarding has represented the beginning of a newborn's independent life. But Blayke and Garrett LaRue, aged 6 and 9, are testimony to a startling medical advance that now connects expectant mothers by umbilical cord to children in need anywhere in the world.
The Los Angeles boys, afflicted with a rare disorder known as X-linked lymphoproliferative disease, were recent recipients of a successful transplant of stem cells harvested from umbilical cord blood of unrelated mothers in New York and Germany. Before the transplant, the disorder rendered the boys' immune systems unable to fight off common infections and left them especially vulnerable to early death from Epstein-Barr virus, a pervasive organism that causes mononucleosis.
By transplanting healthy stem cells -- the immature cells that are plentiful in umbilical cord blood and that have yet to divide and develop specialized functions -- doctors at the University of California School of Medicine in Los Angeles were able to provide the boys with a brand new, functioning immune system. And the use of cord blood meant that Garrett and Blayke did not have to undergo the more painful and traumatic bone marrow transplant.
"I pray daily for those donors," says Theresa LaRue, the boys' mother. "If [the mothers] hadn't donated their cord blood after delivery, my sons would have died. People don't know how important that fluid is."
In 1995, the LaRues' third child, Layne, had died from an infection caused by Epstein-Barr virus. Doctors determined that he had X-linked lymphoproliferative disease and advised the parents to have their other three children tested. In October of that year, two of them, Blayke and Garrett, were diagnosed with the disease.
Bone marrow transplant appeared to be the obvious treatment option, and the parents began an urgent search for a donor who could provide the boys with a new and functioning immune system. But the ubiquitous nature of the Epstein-Barr virus meant they had little time to lose.
"The scary thing was that Layne died of mono, which is everywhere," LaRue tells WebMD. "We were desperate, because we knew if they got mono, it would go so fast."
At the time, using cord blood to transplant stem cells was a relatively novel concept, but an appealing one. For one thing, matching of donor and recipient does not have to be quite as precise when using cord blood as it does when using bone marrow, so the chances of finding a suitable donor were increased. And because of the immaturity of stem cells in cord blood, they are less prone to "graft vs. host" disease, which occurs when the body begins to attack the transplanted cells.
Matches were found for both boys through the National Marrow Donor Program's (NMDP) cord blood bank, and the operations took place at UCLA in 1996 and 1997. Though Blayke was very sick following the transplant, Garret "sailed through" with no complications, according to their mother.
Today, the boys are considered cured. "We are pretty confident," LaRue tells WebMD, noting that subsequent tests indicate the boys have successfully adopted their newly transplanted immune systems. But the proof of the pudding will be when Blayke and Garret contract mono; if their systems successfully fight it off, they and their parents can consider themselves over the hump.
The successful transplants of Garrett and Blayke, and a third child with a similar immune deficiency, were reported in the April edition of the Journal of Pediatrics.
"[The report] points out the great value of stem cell research and of cord blood as an alternative source for stem cells to treat individuals with bone marrow and immunologic disease," author Richard Stiehm, MD, tells WebMD. He is professor of pediatrics at UCLA.
Stiehm says the success stories highlight the importance of donating cord blood. "If you have a bone marrow match from the bank, it's not really in the bank," he explains. "Cord blood banks are true banks of stem cells."
While use of cord blood for stem cell transplant is considered a first-line treatment for the so-called "boy-in-the-bubble" syndrome -- in which children have virtually no immune system at all -- there continue to be hurdles in making cord blood transplants standard for many other conditions, Stiehm says.
For one thing, the volume of stem cells in cord blood is small, and physicians are reluctant to use it in patients who are above a certain body weight, Stiehm tells WebMD.
It was that consideration that leant drama to the success story of the third child.
"Peter" (not his real name) was born with an immune deficiency known as X-linked hyper- immunoglobulinemia M syndrome. Although he required replacement therapy with immunoglobulins and routine antibiotics from birth, Peter's disease had followed a relatively benign course, according to his mother, who asked that the family name not be used.
Yet, doctors at UCLA informed Peter's parents that he could not always count on being so lucky. People with the condition invariably fall victim to chronic liver failure in early adulthood, and few live past the age of 30.
At 11 years of age, Peter already was approaching the maximum body weight considered safe for undergoing a cord blood transplant. So the difficulty of the family's decision to pursue the transplant was compounded by urgency: Do it now or it may be too late.
"Even though he was thriving, his time would be limited," Peter's mother tells WebMD. "We were told that because he was strong, he could make it through the process, and if we waited until a cataclysmic event he would be weak and less likely to endure it."
They opted for the operation. A cord blood donor was located, and the operation was performed in 1997. Today, Peter is 15 and eager to put his ordeal behind him. And like Garrett and Blayke LaRue, he is presumably cured.
LeeAnn Jensen, PhD, immunologist with the National Heart, Lung, and Blood Institute in Bethesda, Md., who reviewed the report for WebMD, says it joins a growing body of evidence showing the benefits of cord blood.
"This is one more report among many that suggests that umbilical cord blood can be used to cure a lot of diseases mediated by diseased blood cells," she tells WebMD.
Jensen says the NHLBI is conducting a national multicenter trial of cord blood transplants for malignant blood diseases and immune deficiencies in children and some adults.
For Theresa LaRue, of course, the verdict is all but in, and she laments the routine discarding of the cord blood that saved her children's lives.
"Doctor's aren't offering [the option of saving cord blood] to their expectant mothers," she says. "It's just so bad that so much of it gets wasted."