Diagnostic and Therapeutic Applications of Microarrays in Lung Transplantation

The current standard for biopsy-based diagnoses of dysfunction of lung transplants is the
International Society of Heart and Lung Transplantation (ISHLT) classification applied to
transbronchial biopsies, which represents an arbitrary international consensus. Recent
data-driven approaches using molecular and conventional technologies indicate that this
system produces frequently incorrect diagnoses with potential harm to patients due to
inappropriate treatment. especially in relationship to the correct diagnosis of chronic lung
allograft dysfunction is a pressing need. To address this unmet need and improve diagnostics
in the area of organ transplantation, the Alberta Transplant Applied Genomics Centre (ATAGC,
University of Alberta) has developed a new diagnostic system - the Molecular Microscope®
Diagnostic System (MMDx) that interprets biopsies in terms of their molecular phenotype. The
MMDx, developed first in kidney transplant biopsies with thoroughly established phenotypes,
will now be adapted to lung transplant transbronchial biopsies (TBBs). Microarray analysis of
lung allograft biopsy specimens will be compared to conventional allograft phenotyping,
including clinical, physiologic, radiographic and histological assessment. The present study
will use the MMDx™ system to assess and report TBBs, and validate and refine this system in
300 unselected prospectively collected lung TBBs. A subset of the study will examine the
third bifurcation mucosal endobronchial biopsies (3BMBs) paired with TBBs from 50 patients to
see if the safer 3BMBs can substitute for the TBB to be used by MMDx™. So far the
investigators collected TBBs from 370 patients and 3BMBs from 263 patients. Due to a
considerable interest and support from participating Centers, the study is further extended
to additional 300 TBBs and 300 3BMBs. Thus this is the extension of the INTERLUNG study -
INTERLUNGEX.

Inclusion Criteria:

- All lung transplant recipients undergoing a biopsy as determined by their surgeon or
physician.

Exclusion Criteria:

- Patients who declined participation or unable to give informed consent.