Researchers from the University of Cambridge have successfully altered the blood type of three donor kidneys, potentially increasing the supply of kidneys available for transplants.
According to the study, published Monday, the groundbreaking discovery could have significant implications for kidney patients and particularly for patients from ethnic minorities, who are less likely to find a match for the majority of donated kidneys.
Patients may only receive kidney donations from donors with the same blood type as theirs, and people within the same ethnic group are more likely to have the same blood type.
“One of the biggest restrictions to who a donated kidney can be transplanted to is the fact that you have to be blood group compatible,” said Mike Nicholson, professor of transplant surgery at Cambridge.
“The reason for this is that you have antigens and markers on your cells that can be either A or B. Your body naturally produces antibodies against the ones you don’t have,” he added.
But this may soon become irrelevant.
Using a normothermic perfusion machine, usually used for pumping oxygenated blood through an organ for preservation, scientists flushed blood infused with a certain enzyme through a deceased kidney.
The enzyme, described in the study as “molecular scissors,” effectively removed specific markers from blood vessels that determined its type, resulting in the blood being converted to the most common O type.
Changing the blood type to the universal O will allow more transplants overall because O can be used for people with any blood group.
“By taking B type human kidneys and pumping the enzyme through the organ using our normothermic perfusion machine, we saw in a matter of just a few hours that we had converted a B type kidney into an O type,” Ph.D. student Serena MacMillan said. B blood type is more common among minority communities, the study said.
Between 2020 and 2021, about nine percent of all organ donations came from black and minority ethnic donors, the study said. At the same time, black and minority ethnic patients make up 33% of the kidney transplant waiting list. Patients from ethnic minority groups can sometimes wait a year longer for a transplant than white patients.
While the study marks a potential breakthrough, scientists will still need to test how the modified O type kidney reacts in patients’ bodies.