Clinical method evaluation of hemoglobin S and C identification by top-down selected reaction monitoring and electron transfer dissociation

Olivier Lassout; Ralf Hartmer; Wolfgang Jabs; Lorella Clerici; Yury O Tsybin; Kaveh Samii; Nicolas Vuilleumier; Denis Hochstrasser; Alexander Scherl; Pierre Lescuyer; Didia Coelho Graça

doi:10.1186/s12014-019-9261-1

Clinical method evaluation of hemoglobin S and C identification by top-down selected reaction monitoring and electron transfer dissociation

Clin Proteomics. 2019 Dec 17:16:41. doi: 10.1186/s12014-019-9261-1. eCollection 2019.

Authors

Olivier Lassout^{1

2}, Ralf Hartmer³, Wolfgang Jabs³, Lorella Clerici², Yury O Tsybin⁴, Kaveh Samii^{2

5}, Nicolas Vuilleumier^{1

2}, Denis Hochstrasser^{1

2}, Alexander Scherl^{1

2}, Pierre Lescuyer^{1

2}, Didia Coelho Graça^{1

2}

Affiliations

¹ 1Department of Medical Specialties, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
² 2Division of Laboratory Medicine, Department of Laboratory Medicine, Genetics and Pathology, Geneva University Hospitals, 4 Rue Gabrielle-Perret-Gentil, 1205 Geneva, Switzerland.
³ Bruker Daltonics, Bremen, Germany.
⁴ 4Spectroswiss, EPFL Innovation Park, Lausanne, Switzerland.
⁵ 5Division of Hematology, Geneva University Hospitals, Geneva, Switzerland.

Abstract

Background: Biological diagnosis of hemoglobin disorders is a complex process relying on the combination of several analytical techniques to identify Hb variants in a particular sample. Currently, hematology laboratories usually use high-performance liquid chromatography (HPLC), capillary electrophoresis and gel-based methods to characterize Hb variants. Co-elution and co-migration may represent major issues for precise identification of Hb variants, even for the most common ones such as Hb S and C.

Methods: We adapted a top-down selected reaction monitoring (SRM) electron transfer dissociation (ETD) mass spectrometry (MS) method to fit with a clinical laboratory environment. An automated analytical process with semi-automated data analysis compatible with a clinical practice was developed. A comparative study between a reference HPLC method and the MS assay was performed on 152 patient samples.

Results: The developed workflow allowed to identify with high specificity and selectivity the most common Hb variants (Hb S and Hb C). Concordance of the MS-based approach with HPLC was 71/71 (100%) for Hb S and 11/11 (100%) for Hb C.

Conclusions: This top-down SRM ETD method can be used in a clinical environment to detect Hb S and Hb C.

Keywords: ETD; Electron transfer dissociation; Hemoglobin; Hemoglobin disorders; Hemoglobin variant; Intact protein; SRM; Selected reaction monitoring; Top-down.