Breakthrough makes all blood types universal

A scientific breakthrough could help alleviate blood shortages and reduce the danger of accidental blood-type mismatches, researchers and executives for a U.S. biotech firm said yesterday.

An international team of scientists announced that it has found a way to convert Types A, B, and AB blood into Type O -- the universal donor blood group that can be given to anyone -- and the American company that commissioned the research said such "universally transfusible" blood has the potential to solve problems associated with storing, transporting and transfusing blood.

"The prospects for this are huge ... since blood now must be transfused on a group-specific basis," Douglas L. Clibourn, chief executive officer of ZymeQuest, said in a telephone interview yesterday.

The team of Danish, English and French researchers reported this week in the journal Nature Biotechnology that it isolated two bacterial enzymes that break down and remove the sugar molecules (antigens) on the surface of A, AB and B red blood cells that can cause potentially deadly immune reactions in patients transfused with mismatched blood.

Under the so-called ABO blood classification system in use for more than a century, Type O blood can be given to anyone, because it lacks such antigens. But Type A blood can only be given to people whose blood is Types A or AB, and Type B blood can only be used in those with blood Types B or AB.

It is costly to ship blood where and when specific types are needed, Mr. Clibourn said. If the new process proves to be safe and cost-effective in clinical trials, "it will allow all red blood cell products to be transfused to anybody, so it will significantly reduce blood shortages," said Samira Johnson, a spokeswoman for ZymeQuest, based in Beverly, Mass.

"About half of U.S. blood centers have less than a three-day supply of blood on hand, and Type O is always the first to go," because is in greatest demand, Ms. Johnson said.

The American Red Cross issued a statement agreeing that "future biomedical technologies ... can improve the nation's blood supply" but also emphasizing that the "need for blood remains critical across the country, regardless of potential breakthroughs in technology."

The research to discover the enzymes to make blood universally transfusible was commissioned by ZymeQuest, which describes itself as the "global leader in the discovery, development, and commercialization of enzymatic blood conversion products for use in blood transfusion medicine."

On its Web site, ZymeQuest.com, the company says its "enzymatic blood conversion system enables the precise and permanent conversions of groups A, B, and AB red blood cells to enzyme converted group O blood cells, known as ECO red cells.

"ECO red cells are functionally the same as group O red cells and like group O red cells may be transfused safely to recipients of any ABO blood group," the company explained.

U.S. data regarding transfusions involving receipt of the wrong blood group or blood components are not readily available, Ms. Johnson said.

"There can be a mismatch, and nothing happens. There can also be a mismatch, and death occurs," she said.

That was the situation at Duke University Medical Center early in 2003, when a 17-year-old Mexican girl, Jesica Santillan, died after a heart-lung transplant in which she received organs from a donor with an incompatible blood type.

In Europe, Ms. Johnson said, there are about 3.3 million transfusions yearly. About 1,500 of them involve giving someone mismatched blood or the wrong components.

Investigators said the promising enzymes are 100 to 1,000 times more powerful than ones used previously. Other assets include the fact that they work at room temperature and neutral pH.

Mr. Clibourn said his company has also devised a tool for keeping the blood units produced sterile.

The concept of stripping antigens from red blood cells to repel immune response dates back to the early 1980s, when an enzyme was discovered in coffee beans that removed B antigens. Early clinical trials showed the converted blood could be safely transfused. However, the approach was far too costly and inefficient to be used on a large scale.

Mr. Clibourn hailed Jack Goldstein, one-time head of cell biology at the Lindsley Kimball Research Institute at the New York Blood Center, for "laying the foundation" for what the European researchers and his firm have achieved. He said use of this technology in blood banks is at least three years away.