Australian man James Harrison, 81, has donated blood 1,173 times, saving the lives of 2.4 million babies, the Sydney Morning Herald reported.

On Friday, he made his final donation.

Harrison's blood contains an unusually high level of an antibody used to prevent hemolytic disease of the newborn (HDN).

This is a potentially deadly condition that can occur when mothers and their unborn babies have incompatible blood types.

Harrison has now passed the Australian Red Cross's donor age limit, but he told the Sydney Herald he'd "keep on going if they'd let me."



James Harrison, 81, made his 1,173rd and final blood donation on Friday — the end of a 60-year donation streak that has saved the lives of 2.4 million babies, the Sydney Morning Herald reported. He's known, unsurprisingly, as "the man with the golden arm."

"It's a sad day for me," he told the Herald. "The end of a long run."

It's not just the high number of donations that makes Harrison's story so noteworthy. His blood plasma also happens to contain unusually high levels of an antibody used to make a lifesaving medicine for babies.

Here's how it works.

Harrison's blood can help women and unborn babies with Rh incompatibility.

"Rh" refers to the Rh factor — a protein on the surface of red blood cells. People who have Rh factor are Rh-positive, and people who don't are Rh-negative, the US National Heart, Lung, and Blood Institute (NHLBI) explains.

If a mother is Rh-negative and her unborn baby is Rh-positive, they have Rh incompatibility — and that can be a problem.

During pregnancy, some of the baby's blood can cross into the mother's bloodstream. If a mom and baby have Rh incompatibility, the mother's body will react to the baby's blood cells like they're foreign invaders, creating antibodies to attack and destroy them.

Some pregnant women and their babies have incompatible blood types. Regis Duvignau/Reuters

In a woman's first pregnancy, this usually isn't a problem, because the baby is born before the mom can develop these antibodies, the NHLBI says.

But the antibodies stick around in a mother's body — and if she becomes pregnant again with another Rh-positive baby, hemolytic disease of the newborn (HDN) can occur, according to Stanford Children's Health. The terrifying complications of HDN may include anemia, jaundice, heart failure, brain damage, and even death.

Rh-negative moms with Rh-positive babies can take a medicine to prevent HDN.

RhD immunoglobulin (also called anti-D) is an injection that can prevent HDN, according to Stanford Children's Health. It's made from the plasma of donors like Harrison. These donors' unique antibodies, when injected into an Rh-negative mother, prevent her body from attacking the Rh-positive baby's cells.

Many women are given doses at the 28th week of pregnancy and again within 72 hours of giving birth, the Stanford Children's Health website adds.

Harrison was inspired to donate after a childhood surgery.

Bags of donated blood plasma. Denis Balibouse/Reuters

When he was 14, Harrison underwent a major chest surgery, receiving blood transfusions that saved his life, according to a statement published by Australian Red Cross Blood Service website. He vowed to become a blood donor himself and began as soon as he was old enough. After more than a decade of whole blood donations, his unique antibodies were discovered, and he switched over to donating plasma instead.

Since 1976, Harrison's blood has been used in more than 3 million injections given to Rh-negative Australian women, the organization says. By analyzing data on Australian births, the percentage of the population that got the injections, and the risk of death from HDN, the Australian Red Cross Blood Service has determined that his donations have saved 2.4 million babies, the Sydney Morning Herald explained.

Now, the Australian Red Cross Blood Service ruled that Harrison should end his donations, according to the Sydney Morning Herald report, since he has passed the organization's donor age limit.

But if Harrison had his way, he'd still be offering up his golden arm to donate even more.

"I'd keep on going if they'd let me," he told the Herald.

If you want to become a blood donor, visit the American Red Cross website and search for a blood drive near you.

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