A Near Point of Care Test for Interleukin 1B During Human Ex-Vivo Lung Perfusion

A.S. Andreasson,1 W. Laroy,2 J.H. Dark,1 A.J. Fisher.11 . J H L T , Vol 37, No 4S,119. p S56 April 2018

The ability to confidently identify which extended criteria donor lungs can be successfully reconditioned via ex-vivo lung perfusion (EVLP) and will function well post transplant is essential. IL-1β is a promising early perfusate marker shown to differentiate between 1-year post-Tx survival and mortality with high precision in EVLP recipients (p=0.005, AUC=0.93). However, the typical EVLP assessment time before a decision on transplant suitability has to be made is as short as two-four hours. For any biomarker technology to have real clinical relevance it has to be highly accurate and able to deliver a result available to the clinical team at time of decision-making. In this study, the semi-automated Evalution™ platform (MyCartis) with an assay time <60min was assessed and compared with our standard overnight MSD multi-array.

The Evalution™ technology utilizes the “co-flow” principle of simultaneous incubation of sample, detection antibody (BAF201) and disk-shaped microparticles as capture antibody carriers, anti-IL-1β (MAB201; R&D Systems), to reduce the manual interventions to a few pipetting steps. In the microfluidic environment only short incubation times are needed to reach saturation with fluorescent monitoring of binding events occurring in real-time. Here, IL-1β levels in perfusate samples collected after 1hr of perfusion from 46 clinical EVLP lungs in the DEVELOP-UK study (ISRCTN 44922411) were analyzed with the Evalution™ platform and compared with levels on the MSD V-plex multiarray.

Four samples had undetectable IL-1β levels on the MSD platform (<0.1pg/ml); All were detectable on the Evalution™ system with levels <1pg/ml. Apart from these very low level samples the correlation between the two assays was linear (all samples (n=46) r=0.88, discrepant samples excluded (n=42) r=0.99). Importantly, equal to the MSD array, IL-β levels on the Evalution™ system remained highly specific and sensitive in diagnosing 1-year post-Tx mortality in this group of recipients (p=0.003, AUC=0.97) with excellent dilution response and inter and intra assay reproducibility.

This study demonstrates a novel fast and sensitive assay strengthening the potential of using early pro-inflammatory markers in perfusate to identify donor lungs most likely to improve to successful transplantation during clinical EVLP.