Evidence-based Decision Making
Limitations in Conventional Biopsy Diagnosis
As you know, clinicians often rely on histopathology scores when assessing injury or rejection in a troubled transplant, but these scores are empirically-derived, subjective, and opinion-based. Studies have shown that TCMR diagnosis concordance rates between pathologists vary greatly by organ due to the subjective nature of these diagnostic systems.
In addition, histology results are limited
by the quality of the biopsy samples.
Up to 20% of lung biopsies cannot be
read at all. Furthermore, acute injury is
poorly represented by histology.
A New Era of Precision Medicine
The development of genomic sequencing tools along with a large amount of digital big data on individuals and populations are making precision medicine a reality. The Molecular Microscope® Diagnostic System (MMDx™) combines these technologies to overcome the limitations of conventional histology and deliver objective and reproducible transplant biopsy assessments.
MMDx is providing a new understanding of an organ's reduced function in response to injury. The molecular profile of a biopsy can not only signal ongoing, and often subclinical immune-mediated injury but can also identify acute T cell-mediated rejection (TCMR) even in samples without histological evidence of inflammation.
Because increased diagnostic accuracy can eliminate confusion between transplant rejection and organ injury, treatment can be more precise, and the administration of unnecessary immunosuppression drugs can be prevented.
Using an objective scientific approach instead of by eye, we can look at the molecular signature of a biopsy to make a more accurate diagnosis.*
Andrew Fisher, PhD
Institute of Transplantation at Freeman Hospital
Newcastle Upon Tyne, United Kingdom
MMDx Helps Assess Transplant Injury and Rejection
MMDx is a central diagnostic system that uses microarrays to measure transcript levels in biopsies. An algorithm is then applied to compare the biopsy to a Reference Set of samples and assign quantitative scores to stratify rejection and injury risk in kidney, heart and lung transplant patients.
Better understand how MMDx improves on the standard of care
Advantages of MMDx vs. Histology
Minimally invasive: Requires less tissue than histology
Convenient: Simply put biopsied tissue into a prepared tube (containing RNAlater®) at room temperature
Fast turnaround: Results available 1-2 business days from receipt of sample
Actionable data: Provides objective, quantitative, probabilistic risk assessment
How Does MMDx Work?
mRNA is produced inside
transplanted tissue when DNA genes are expressed or active.
Depending on the risk or severity of organ rejection and injury, particular genes will be activated and produce unique patterns of mRNA.
MMDx accurately analyzes
thousands of different mRNA to provide you and your doctor precise information about the health of your transplanted organ to create a personalized treatment plan.
The MMDx Process
1. Collect Biopsy
Kidney or liver:
5 mm of biopsy or portion ofcore
Heart or lung:
3. Process Specimen
The mRNA levels are measured on a microarray and algorithms, based on a large Reference Set of biopsies at the lab