Scientists have devised a non-invasive way to determine if a transplanted organ – such as a kidney, liver, lung or heart – is not being accepted well by the patient.
This is the first time that biomarkers of dysfunction have been consistent across multiple transplanted organs, suggesting the possibility of a blood test that could diagnose early rejection. all Porting scenarios – tools that don't exist yet.
With further research, the newly identified biomarkers may also be used to distinguish between different types of organ rejection, including those due to immune problems, inadequate blood supply, and maladaptive repair.
Transplant survival rates vary by organ, with long-term success rates of 59% for lungs, 80% for livers, 82% for kidneys, and 73% for hearts. May occur Recurrence can occur at any time after surgery, even years later, and poses a lifelong threat to patients.
Usually, doctors Suspect Transplant rejection occurs when there are signs that the organ in question is not functioning adequately, but patients may not experience any symptoms before failure occurs, and an invasive biopsy is the only way to know for sure what's going on.
In recent years, several studies have been conducted to look for signs of organ rejection in patients' blood. blood or urine It is easier to access than surgery. Potential biomarkers The rejection events identified so far are not yet used in clinical practice and therefore cannot predict all organ rejections, but usually only one type of rejection.
The current study is a meta-analysis that aims to fill that gap. The authors, led by statistician Harry Robertson of the University of Sydney, analyzed 54 data sets, including 40 kidney transplant studies, five lung transplant studies, five liver transplant studies, and four heart transplant studies.
By comparing blood samples and biopsies from each patient, the team identified 158 genes that were differentially expressed in all four organs during rejection — about 20 times more than would be expected by chance.
“This discovery is crucial because it will allow us to develop strategies to improve the success rate of any transplant.” explain Robertson.
Some of these common biomarkers are proteins that stimulate white blood cells, enzymes that induce cell death, receptors on cells that allow substances to enter or leave, and secretions of bone marrow cells involved in the immune response.
Robertson and his team Assert Their findings demonstrate a “uniform whole-organ molecular marker” that their method “consistently outperforms” other organ-specific models currently being refined for clinical use.
but, Robertson and his team's method It is used in pancreas, stomach, and intestine transplants.
The research team has created an interactive website that allows scientists around the world to compare their potential biomarkers of transplant rejection with other methods, providing a much-needed standardized assessment.
“This atlas led to the development of a proof-of-principle universal blood test that can predict the likelihood of transplant rejection before it occurs,” Robertson said. To tell“It has the potential to establish a new standard in precision medicine and improve outcomes for transplant patients around the world.”
Since 1989, one-year survival rates for kidney transplants, the most common type of organ transplant, have improved significantly, but long-term survival rates have stagnated.
Part of the problem is that doctors still don't have an easy way to confidently assess the early stages of organ rejection, when drug intervention might alleviate the problem before the organ fails completely and a second transplant is required.
“I noticed that many of my patients have a constant sense of anxiety about not knowing if their body is rejecting a transplanted organ.” explanation Lorenzo Garrone (2023), a transplant nephrologist at Northwestern Medicine who is researching ways to detect early rejection.
“They wait years for a transplant, then finally receive an organ from a loved one or a deceased donor, and then spend the rest of their lives worrying about the health of that organ.”
The situation could be improved with reliable blood tests to monitor transplant rejection.
This study Nature Medicine.
