Organ transplantation saves lives, but finding a compatible donor and recipient often takes a long time, in part because blood type has to match. Type O organs are considered universal donors, meaning they can go to a patient with any blood type.

Avivo Biomedical Inc., a BC biotechnology company, has discovered enzymes that can strip the markers that determine blood type (called antigens) off type A organs.  This could turn a type A kidney into a type O kidney, expanding the pool of organs available to patients with end-stage renal disease.

This project, led by Jay Kizhakkedathu at the University of British Columbia in collaboration with Peter Rahfeld of Avivo Biomedical Inc., investigated whether A antigens return after they’re removed using the enzymes and whether a technique called gene-silencing could stop them from returning.

Using human kidney blood vessel cells that express A antigens, the researchers showed that A antigens reappear after they’ve been removed by the enzymes. They also found that growing these cells for longer periods affected both antigen markers and cell growth.  

To stop the markers from returning, the team utilized a gene-silencing technique (small interfering RNAs or siRNAs) to suppress the gene responsible for A-antigen production. The siRNAs successfully reduced gene activity and, under some conditions, lowered A-antigen levels on the cell surface.

Overall, the project established a useful laboratory model for this research and found early evidence that gene silencing may help prevent A-antigen markers from returning after enzymatic removal. Further optimization and validation of the of the model is needed beyond this project.