Good news! Implanted into an older brain-dead man??? Abuse?
"For the first time, scientists have converted the blood type of a donor kidney and transplanted the organ into a person. The team used an enzyme to remove type-A antigens from the kidney. This made it a type-O organ, which is compatible with all blood types. The organ was transplanted into a 68-year-old brain-dead man and remained healthy for two days before showing signs of rejection. The procedure could improve access to donor organs and reduce wait lists, says transplant clinician ..."
"... In a first-in-human experiment, the enzyme-converted kidney was transplanted into a brain-dead recipient with consent from the family, allowing researchers to observe the immune response without risking a life.
For two days, the kidney functioned without signs of hyperacute rejection, the rapid immune reaction that can destroy an incompatible organ within minutes.
By the third day, some blood-type markers reappeared, triggering a mild reaction, but the damage was far less severe than in a typical mismatch, and researchers saw signs that the body was beginning to tolerate the organ. ...
The key to this approach is the 2019 discovery by the UBC team of two highly efficient enzymes that remove the sugar that defines type-A blood, effectively converting it to type O. “These enzymes are highly active, highly selective, and work at very low concentrations,” ..."
From the abstract:
"ABO-incompatible kidney transplantation is widely used to meet the escalating need for organs. Current recipient-centric desensitization protocols involving antibody depletion through plasmapheresis increase the risk of infections, perioperative bleeding events and costs.
Here we present a donor-centric desensitization protocol, converting type-A kidneys into enzyme-converted O kidneys during hypothermic perfusion to remove the A antigen from the kidneys.
An ex vivo model resulted in no antibody-mediated injury. Encouraged by this, an enzyme-converted O kidney was transplanted into a type-O brain-dead recipient with a high titre of anti-A antibody, and no hyperacute rejection was observed. The graft was well tolerated with no evidence of antibody-mediated rejection for 2 days.
Antibody-mediated lesions and complement deposition were found starting 3 days post-transplant, coinciding with A-antigen regeneration, and later higher Banff scores, suggesting an immune-mediated response.
Single-cell sequencing confirms the elevated expression of accommodation-related genes, suggesting the potential for longer-term tolerance.
This study provides a donor-centric organ engineering strategy and has the potential to broaden the reach of ABO-incompatible kidney transplantation, improving the fairness of and access to organ allocation."
First human transplant of kidney modified to have ‘universal’ blood type "Recipient diagnosed with brain death received a type-O organ, which is compatible with all blood types."
UBC enzyme technology clears first human test toward universal donor organs for transplantation (original news release)
Enzyme-converted O kidneys allow ABO-incompatible transplantation without hyperacute rejection in a human decedent model (no public access, but article above contains link to PDF)
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