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Licensed Unlicensed Requires Authentication Published by De Gruyter September 2, 2020

Determination of free light chains: assay-dependent differences in interpretation

Xavier Bossuyt, Koen Poesen, Ben Sprangers, Martin Reynders, Martine Vercammen and Michel Delforge

Corresponding author: Xavier Bossuyt, Department of Microbiology, Immunology and Transplantation, Clinical and Diagnostic Immunology, KU Leuven, Leuven, Belgium; and Department of Laboratory Medicine, University Hospitals Leuven, Herestraat 49, 3000 Leuven, Belgium, Phone: +32 16 347009, Fax: +32 16 34 79 31, E-mail:


We thank Siemens and The Binding site for providing the reagents and for performing the assays.

We thank Carola Wagner, Oscar Berlanga, and Stephen Harding for helpful discussions. BS is a senior clinical investigator of The Research Foundation Flanders (F.W.O.) (1842919N).

  1. Research funding: None declared.

  2. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  3. Competing interests: BS has received an unrestricted research grant from The Binding Site.

  4. Informed consent: Informed consent was obtained from all individuals included in this study.

  5. Ethical approval: The study was approved by the Ethics Committee of the University Hospitals Leuven and is in compliance with the World Medical Association Declaration of Helsinki.


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Supplementary Material

The online version of this article offers supplementary material (

Received: 2020-06-17
Accepted: 2020-08-04
Published Online: 2020-09-02
Published in Print: 2021-02-23

© 2020 Walter de Gruyter GmbH, Berlin/Boston