Myocardial Gene Expression Profiling to Predict and Identify Cardiac Allograft Acute Cellular Rejection: The GET-Study

PLoS One. 2016 Nov 29;11(11):e0167213. doi: 10.1371/journal.pone.0167213. eCollection 2016.

Abstract

Aims: Serial invasive endomyocardial biopsies (EMB) remain the gold standard for acute cellular rejection (ACR) diagnosis. However histological grading has several limitations. We aimed to explore the value of myocardial Gene Expression Profiling (GEP) for diagnosing and identifying predictive biomarkers of ACR.

Methods: A case-control study nested within a retrospective heart transplant patients cohort included 126 patients with median (IQR) age 50 (41-57) years and 111 (88%) males. Among 1157 EMB performed, 467 were eligible (i.e, corresponding to either ISHLT grade 0 or ≥3A), among which 36 were selected for GEP according to the grading: 0 (CISHLT, n = 13); rejection ≥3A (RISHLT, n = 13); 0 one month before ACR (BRISHLT, n = 10).

Results: We found 294 genes differentially expressed between CISHLT and RISHLT, mainly involved in immune activation, and inflammation. Hierarchical clustering showed a clear segregation of CISHLT and RISHLT groups and heterogeneity of GEP within RISHLT. All EMB presented immune activation, but some RISHLT EMB were strongly subject to inflammation, whereas others, closer to CISHLT, were characterized by structural modifications with lower inflammation level. We identified 15 probes significantly different between BRISHLT and CISHLT, including the gene of the muscular protein TTN. This result suggests that structural alterations precede inflammation in ACR. Linear Discriminant Analysis based on these 15 probes was able to identify the histological status of every 36 samples.

Conclusion: Myocardial GEP is a helpful method to accurately diagnose ACR, and predicts rejection one month before its histological occurrence. These results should be considered in cardiac allograft recipients' care.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Allografts
  • Biomarkers / metabolism*
  • Case-Control Studies
  • Female
  • Gene Expression Profiling*
  • Graft Rejection / diagnosis*
  • Graft Rejection / genetics
  • Heart Transplantation / adverse effects*
  • Humans
  • Male
  • Middle Aged
  • Myocardium / metabolism*
  • Myocardium / pathology
  • Retrospective Studies
  • Young Adult

Substances

  • Biomarkers

Grant support

This work was supported by the non-profit organization AREMCAR (Association pour la Recherche de l’Etude des Maladies Vasculaires) and with an institutional grant from Novartis to support the collection of the clinical data. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.