The transplant surgery may be the first big hurdle patients have to get through, but it’s certainly not the last. For all transplanted organs, the definitive way to check for rejection is with an invasive biopsy. This is a catheter procedure done under general anesthetic for pediatric patients, minimal or no anesthetic for adults. During the procedure, small samples of organ tissue are taken with tiny tweezers. Those samples are examined by a pathologist for signs of rejection. The results can potentially be inaccurate because the samples may come back negative even if there is rejection in other parts of the organ.
Research at St. Paul’s Hospital and the PROOF Centre is about to change that, starting with cardiac patients. They are set to launch the clinical validation of biomarker testing for rejection. Instead of a biopsy, a simple blood test can determine if the patient is in rejection. Not only is it far less invasive and less costly, the results can be as accurate or even a little better than a biopsy. Researchers are now looking at biomarkers for other organs too, so a blood test for rejection could soon become the standard for follow-up care of all transplant patients.
Infection used to be a major life-limiting complication for transplant recipients, but with better diagnostics and treatment, outcomes have great improved. At the same time, there is research on personalizing the amount of immune-suppressing drugs each patient actually needs. One recent discovery by Dr. Seema Mital at SickKids in Toronto is how genetics plays a role in the absorbtion of the medications. Turns out most Caucasians lack the gene to clear the drugs, whereas Asians and blacks have the gene. This means some patients need less of the drug and others may need more for the same therapeutic effect. The hope is by using genetic sequencing, doctors will be able to offer personalized medicine for transplant patients, allowing some to take a smaller doses while ensuring others have enough to prevent rejection.
London Health Sciences Centre is home to the Matthew Mailing Centre, a research facility dedicated to translational transplant research. It’s the only one of its kind in Canada and fully funded by private donations. There are currently 300 investigators working on dozens of different projects, all of them trying to make a difference in the lives of transplant patients. Right now the focus is on how cells die. A donor organ starts to go through the dying process before it is transplanted and that causes inflammation in the recipient, plus they are receiving a damaged organ which compromises the longevity of that transplant. Dr. Anthony Jevnikar’s work shows there are at least 15 forms of cell death, and some of those can be regulated with drugs. This could help the recipient accept the organ better with less chance of rejection.
Watch News Hour at 6 p.m. on Friday for the finale of the special series.
Part 1 – The search for a cure
Part 2 – Unlocking the secrets of the immune system