LOUISVILLE, Ky. (AP) — The trio of Sigma Chi fraternity brothers signed up at the University of Louisville for a stem cell donor registry in 2009 and didn't give it a second thought.
Given the odds of matching someone— only one in 540 people who register ever are — 22-year-old Max Voorhies, 22-year-old Matt Venard and 22-year-old Cameron Tillett never expected to get the call.
Then, figurative lightning struck. Within a year, Voorhies found himself hooked to a machine to filter stem cells out of his blood. Early last year, Venard got the call. Then in March of this year, the donor registry came calling for Tillett.
"I've never heard of that before," said Dannie Moore, an account executive with the National Marrow Donor Program who organizes drives at the university.
All three turned out to be perfect matches for patients in need of stem cells, and all three made donations. The chance of such a coincidence is exceedingly low, according to officials at Be the Match, which organized the drive at the school.
Stem cell donations are vital for patients whose bone marrow has stopped functioning correctly, Dr. Roger Herzig, who directs the blood transplant program at U of L told The Courier-Journal (http://cjky.it/14D0sGo).
"It can be life-saving," Herzig said. Recipients who need the cells suffer from diseases such as sickle cell anemia, in which the body produces deformed red blood cells due to a defective gene, and cancers of the blood or bone marrow.
More than 12,000 people in the nation are diagnosed with such diseases every year, according to the National Marrow Donor Program.
Stem cells derived from the blood or bone marrow can form all other types of blood cells, such as the red blood cells that transport oxygen to tissues and the white blood cells that fight infection.
It can be difficult to find a donor who matches the recipient's tissue type well enough for the transplant to work. Unlike blood, which has the three basic familiar types (A, B and O), stem cells have 10 "markers," or surface proteins, that identify them to the host's immune system.
Doctors prefer in-family donations. The National Marrow Donor Program estimates that 70 percent of patients do not have a match in their families. The national Be the Match Registry keeps tabs on about 100,000 potential donors who could be matched to patients.
A match that isn't close enough can prompt a recipient's existing immune system to reject the transplant. In other cases, since the transplant gives rise to immune cells, recipients can suffer from a syndrome called graft versus host, in which the transplanted cells mount an immune response against the donor's body, Herzig said.
Because of the specificity needed to match donors and recipients, the National Marrow Donor Program has aggressively sought to sign up donors to grow the pool of possible matches. Potential donors who belong to minority groups are particularly in demand.
The identity of the recipients is kept secret for their privacy.
Voorhies knows that his recipient was a 52-year-old male who died several months after the transplant.
"It was a lengthening-of-life kind of operation," Voorhies said, adding that he hoped his donation improved the patient's life, if even for a short time.
Venard received a Christmas card from his recipient, a 5-year-old girl with leukemia.
"She calls the bone marrow her 'factory,' because it produces new blood cells," Venard said. The front of the card said "Thanks for the factory," and on the inside it read "I feel good."
"That was one of the most rewarding cards I've ever gotten," he said.
Because he only recently donated, Tillett hasn't heard anything yet about the recipient of his stem cells.
"I felt I had an obligation to do it," Tillett said. "There was a brief moment when I could have said no. ... But I felt like I had to, really."