Six surgeries. Two countries. Three lives saved.

Politics and science combined this past summer to make a series of historic, life-saving organ donations possible, all due to work done by Stanford University Israeli professor Itai Ashlagi.

Ashlagi, working with a graduate student from Thailand, developed the software and algorithm instrumental in linking a chain of “pay it forward” matches between kidney donors and recipients in Israel and the United Arab Emirates. The exchange was the first between Israel and an Arab nation and made possible because of the 2020 signing of the Abraham Accords normalizing relations between the two countries.

“It’s good if we can exchange kidneys and not rockets,” Ashlagi told J. in an interview. Graduate student Sukolsak Sakshuwong aided the effort.

In the exchange, an Israeli woman donated one of her healthy kidneys to an ailing recipient in Abu Dhabi. Meanwhile, the daughter of the Emirati recipient donated one of her healthy kidneys to a different Israeli woman in need of a transplant. That patient’s husband was a match and donated a kidney to the first Israeli donor’s mother.

“Itai’s software was used on both sides of that historic exchange between Abu Dhabi and Israel,” said Alvin Roth, a Nobel-winning economist who is Ashlagi’s longtime mentor, and who was in Abu Dhabi in connection with the exchange.

In kidney transplant lingo, such complex transactions are known as a cyclic exchange.

Ashlagi’s algorithm, which is used by organizations around the world, including Israel’s National Transplant Center, is designed to facilitate those transactions. It may seem abstract, but it has real-life results.

Kidney donations rely on matches. Someone may want to donate to a loved one, but if they’re not a biological match, it won’t work. Using Ashlagi’s algorithm, a donor may still be able to save a loved one’s life, just in a different way.

“Lots of people have someone who loves them [but is] incompatible, but they don’t know about this possibility, that this exists,” Ashlagi told J. “Not all transplant centers are involved in these kinds of things. But it’s out there, and it’s possible to do.”

Without the Abraham Accords and Ashlagi’s collaboration with the Alliance for Paired Kidney Donation and Israel Transplant, the Israelis and the Emiratis likely would never have known about each other and the complex matching would have been a longshot, at best.

In addition to the biology of blood typing and tissue matching, which includes factors such as blood type, antibodies and even the patient’s age and proximity to the donor, the team must also wrestle with data-related challenges to permit the various hospitals in an exchange to share information easily and with confidence.

At the most basic level, Ashlagi and others in his field view kidney exchanges as a marketplace. Not in the crude monetary sense — Ashlagi, in fact, offers his algorithm for free and receives no royalties or other compensation for its use. But it is a market, nonetheless, in the sense that it matches supply and demand. The currency, however, is measured not in dollars and cents but in years of life restored to people with serious illnesses. Ashlagi estimates that around 800 matches have been made with his software.

Ashlagi, who studies market design and game theory, got his undergraduate degree and Ph.D. in Haifa, the latter at the Technion, then went to Harvard for postdoc studies. He has been teaching at Stanford since 2015, after a stint at M.I.T. But he’s been inside the marketplace of kidney donations since he was a postdoc working under Roth, who won his Nobel in 2012 for his contributions in “matching markets,” where price isn’t a key factor — such as the market for organs.

Roth said Ashlagi exemplifies the concept of scientist-engineer and is now a driving force in contemporary kidney exchange through his deep understanding of the immunological issues of matching kidneys to patients, as well as his intimate appreciation of the needs of transplant centers.

“He’s turned those practical theoretical insights into widely deployed digital tools with the power to change lives,” Roth added. “Having the chance to collaborate with him has been among the best experiences of my intellectual career.”

This story was adapted from an article by Andrew Myers in Stanford Engineering Magazine.