BANKING ON CORD BLOOD

 

Umbilical ‘waste’ is gradually becoming an alternative to bone marrow for transplants.

 

When H.Baker entered the world on Dec.30, his parents shelled out an extra $1200 to have blood from their son’s umbilical cord collected and processed through a private cord blood bank in California.

They’ll continue to pay about $100 a year to store the frozen extract until their son is 18, on the outside chance that Harrison or an immediate family member might one day need a bone marrow transplant.

Cord blood remains in the umbilical cord and placenta after birth. It contains the same building blocks of the immune system as bone marrow – stem cells that are capable of restoring a damaged blood system and repopulating the body’s red and white blood cells and platelets.

Scientists discovered in 1988 that cord blood, long discarded as medical waste, was the only known substitute for bone marrow transplantation. So far, cord blood has been used to restore bone marrow that’s been ravaged by about 30 different illnesses, including certain cancers, leukemias, blood diseases and immune system disorders.

Harrison’s banked cord blood would be an identical match to his own bone marrow. The boy’s close relatives could also benefit, because the odds of a good match are increased within families.

Cord blood’s overlooked wealth has been called the ultimate in recycling, as research and technology rescue from medical waste a treasure trove of life-giving stem cells. The Harvard Health Letter named umbilical cord blood “recycling” as one of the top 10 medical advances of 1996.

The odds that Harrison will ever need his cord blood could be as long as 1 in 200,000. But a growing number of commercial cord blood banks are flourishing, given life by the fact that if there’s a way to protect children from life’s caprice, parents who can afford a little biological insurance are often eager to pay.

Although the first successful cord blood transplant occurred a decade ago, the opportunity for families to collect and store umbilical cord blood privately has been widely available only since about 1995. Many expectant mothers have never heard of it.

Harrison’s mother was unaware of cord-blood retrieval and his life-saving potential until she read about umbilical cord blood banking in a Dear Abby column about three weeks before her son’s birth. She showed the column to her husband and “it just grabbed them”.

The frozen vials of Harrison’s blood will become his property at age 18. At that point, Harrison could donate the blood to a federally financed cord-blood bank – now few in number – that would make the blood available to anyone in need. Or, Harrison or his parents could continue to pay to store it for themselves or other family members who might be an acceptable match.

 

BLOOD

 

Stem cells are the progenitors of all the body’s specialized cells. Previously found only in bone marrow, stem cells contain the essential ingredients for healthy blood and immune systems.

When bone marrow is weakened or destroyed by disease or by chemotherapy and radiation administered to fight disease, the therapy of last resort is a bone marrow transplant.

But there isn’t enough bone marrow available through national and international registries to meet the need. Each year, up to 15,000 people are unable to find a suitable bone marrow donor.

Cord blood transplants are helping meet the demand. So far, about 2,000 cord blood transplants have been performed worldwide, mostly on children. About a quarter of them used cord blood from siblings, while the reminder were from donated cord-blood samples, according to the Cord Blood Donor Foundation, a not-for-profit organization backed by private donations.

About 2 ½ years ago, the National Heart, Lung and Blood Institute, part of the National Institutes of Health, began a five-year, $30 million study on the effectiveness of cord-blood transplants from unrelated donors. Scientists hope that the work will help advance a national cord-blood registry.

The study is gathering evidence on the appropriate dose of cord-blood cells needed for patients of different weights. Because there is only a small amount of blood contained in the umbilical cord, the sample is often insufficient to treat someone who weighs more than about 110 pounds, according to Dr. S.Y., a hematologist, oncologist and medical director of the bone-marrow transplant program at Virginia Commonwealth University’s Medical College of Virginia.

However, while cord blood contains a lower volume of stem cells than the amount available from bone marrow donors, the cells are more concentrated and adaptable. The ‘naïve’ cells have not yet committed to specific tasks, as they have in an adult bone marrow donor. So cord blood from unrelated donors doesn’t have to match as specifically as unrelated bone marrow.

 

The young cells also are less likely to trigger a potentially lethal immune system reaction known as graft-vs.-host disease, which causes the donor cells to attack the recipient’s tissue. That has fueled hope that cord blood transplants could make a big difference for minorities who are underrepresented in bone marrow donor pools.

For now, though, there are government-financed cord-blood collection and storage programs at only a handful of U.S. medical teaching centers. Cord-blood donation for public use, meaning that it is available to any patient who needs a transplant, is unavailable in most communities. The National Marrow Donor Program, which maintains a national registry of bone-marrow donors, is also collecting data for a cord-blood registry.

So far, only about 15000 to 20000 cord blood samples are publicly available, Yanovich said. By comparison, more than 3 million people have signed up to donate their bone marrow if it’s needed to save a life.

“If we don’t find a bone-marrow donor in the registry, we pursue the cord blood,” said Yanovich.

Building a cord-blood collection and storage program is an expensive proposition, and the federal government has not yet committed itself to a nationwide effort that would collect, test, preserve, and store umbilical cords. However, the Cord Blood Donor Foundation, a not-for-profit group, is building an ethnically balanced stem cell bank through private donations.

While government input is limited, the Nov.26 issue of the New England Journal of Medicine reported that 562 cord-blood transplants had been performed with cord blood banked at government expense at the New York Blood Center. The article showed that the procedure can be effective even when the donor is unrelated and does not have a complete antigen match. Antigens are part of every cell, and they’re capable of stimulating an immune response. So blood is typed according to antigens, a critical consideration in all types of transplants, to help prevent the foreign substance from attacking its host.

The big breakthrough in cord-blood transplantation occurred in October 1988, when a Paris doctor performed the first cord-blood transplant on a 6-year-old American boy, Matthew Farrow. Matthew was at the end of his options after a lengthy international bone-marrow search had failed to turn up a suitable match. He was losing his battle against a genetic blood disease called Fanconi’s anemia, which usually kills its victims by age 12.

That’s when Matthew’s parents decided to conceive their third child a little ahead of schedule, in hopes that the infant’s bone marrow would be an acceptable match for their dying son. Doctors knew that if the infant’s bone marrow matched Matthew’s, so would her umbilical cord blood.

 

In utero tests showed that it did, and little Dorothy Farrow helped save her brother’s life soon after her birth.

Seven years later, there was still no sign of the deadly disease, and a new era in cord-blood transplantation was under way.

Since September 1997, the University of Virginia Medical Center has performed six cord-blood transplants from unrelated donors. Three died from infections after the transplant – a not-uncommon outcome whenever one’s damaged bone marrow is destroyed so healthy stem cells can take root.

Some scientists criticize commercial banks, saying they prey on the fears of protective parents.

“They’re just basically using a scare tactic,” Yanovich said. “I think they’re playing with the fear just to make more money.”

Because the likelihood is so remote that a particular child will require a transplant, Yanovich thinks cord blood should be collected and distributed for the public good, “saved for everybody.”

J.Kurtzberg of Duke University, an early pioneer in cord blood transplant, agrees that very few children whose cord blood is stored at private banks will ever need it.

“The public bank, in contrast, makes units available to anyone who matches,” she said in a recent article in the Duke University Research Magazine. “It seems to be a better use of resources.”