EBMT 2018 | Elafin is a potential biomarker for acute skin GvHD

Acute graft-versus-host disease (aGvHD) is a multisystem disorder that is a common complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is a reaction between donor immune cells and host tissues. Recent studies have identified a number of tissue-specific proteins as potential predictive biomarkers that could improve early and accurate diagnosis of the condition. The role of a lead biomarker candidate, elafin, in skin GvHD was investigated by Laura Solán from Hospital General Universitario Gregorio Marañón, Madrid, Spain et al.

On behalf of colleagues, Laura Solán reported results from their retrospective study at the 44th Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT) in Lisbon, Portugal.

Solán et al. analyzed 110 consecutive patients (median age = 46 [range, 16–66]) who underwent haploidentical HSCT with post-transplant cyclophosphamide on Days 3 and 4, using MMF and CsA as GvHD prophylaxis between 2009 and 2016. In total, 23 cases were excluded; nine due to early death before Day 30, and 14 due to lack of plasma sample.

Key findings:

• Cumulative incidence (CI) of grade II-IV and grade III-IV aGVHD at 100 days:
• 51.5% and 14.2%, respectively
• CI of grade II-IV and III-IV cutaneous aGVHD at 100 days:
• 50% and 8%, respectively
• CI of relapse and NRM at 2 years:
• 30% and 22.2%, respectively
• 2-year OS: 60%
• 2-year EFS: 40%
• aGvHD and clinical variables (age, sex, conditioning regimen, donor/recipient sex, stem cells source and number of infused CD34⁺ cells) did not correlate
• Plasma elafin levels on Day 15 were significantly higher in patients who developed grade III-IV skin aGVHD compared to those who did not: 21.313 (14.014 – 22.001) vs 14.974 (843 – 22.110) pg/ml, P = 0.003
• Plasma elafin levels on Day 15 were higher in patients with grade II-IV skin aGVHD: 18.481 (4.887 – 22.119) vs 14.692 (8.43 – 21.448) pg/ml, P = 0.2
• Patients with elafin levels higher than 20.373 pg/ml on Day 15 had a significantly higher incidence of grade III-IV skin aGVHD: HR = 16.3, P < 0.001
• To stratify patients with grades III-IV skin aGvHD, the best cut-offfor elafin levels on Day 15 was 20,373 pg/ml

Plasma elafin levels after haplo-HSCT on Day 15 significantly correlated with the incidence of grade III-IV skin aGVHD. There was no association found between elafin levels at Day 15 and 30 and other organ-involvement of GvHD. Hence, the study authors found that elafin seemed to be a good predictive marker in skin aGVHD, therefore, to optimize treatment in these patients. Prospective trials are required to confirm these findings.