Article Text

Download PDFPDF
Modes of assay interference and the effectiveness of serum pretreatment approaches in detection of anti-HLA antibodies
  1. Joseph Abraha1,
  2. Ping Rao2,
  3. Gerald P Morris1
  1. 1 Department of Pathology, University of California San Diego, La Jolla, California, USA
  2. 2 Aurora Health Care, Milwaukee, Wisconsin, USA
  1. Correspondence to Dr Gerald P Morris, University of California San Diego, La Jolla, California 92093, USA; gpmorris{at}


Aims Several modes of assay interference common to immunoassays affect solid-phase single-antigen bead-based immunoassays (SAB) used to detect antibodies against human leucocyte antigens (HLA). Best practice recommendations include methods to address assay interference, though the clinical impact and optimal approaches are undefined. We sought to evaluate assay interference in HLA SAB to identify an efficient approach for avoiding erroneous results.

Methods Retrospective analysis of 14 059 patient samples tested for anti-HLA antibodies was performed. This included 4685 samples tested prior to implementation of serum pretreatment with EDTA and 4982 samples tested with routine EDTA treatment using the same testing algorithm. An algorithm for efficiently identifying and processing samples with suspected interference was evaluated in a separate cohort of 4392 EDTA-treated samples.

Results EDTA serum pretreatment reduced assay interference, but did not eliminate all modes of interference. A protocol for identification and testing of samples with suspected interference facilitated efficient detection of interference while reducing the amount of additional testing required.

Conclusions Our data indicate that a single-method approach is insufficient to address all sources of interference in HLA SAB. A multimodal approach with a proactive screening is a more effective way to minimise risk of erroneous results.

  • HLA Antigens

Data availability statement

All data relevant to the study are included in the article or uploaded as online supplemental information.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Data availability statement

All data relevant to the study are included in the article or uploaded as online supplemental information.

View Full Text


  • Handling editor Tahir S Pillay.

  • Contributors JA and PR collected and analysed data and participated in writing the manuscript. GPM designed the study, collected and analysed data, and wrote the manuscript. GPM accepts full responsibility for the finished work and/or the conduct of the study, had access to the data, and controlled the decision to publish.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests GPM is a Scientific Advisory Board member for Transplant Diagnostics for Thermo-Fisher/One Lambda and has received research and travel support from Thermo-Fisher/One Lambda.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.