Subtyping of systemic amyloidosis in subcutaneous fat aspirates by mass spectrometry-based proteomics analysis

Introduction

The systemic amyloidosis is a multiorgan disease with significant morbidity and mortality. Early diagnosis is critical for effective patient management. Examination of abdominal subcutaneous fat aspirates (SFA) is a low invasive method for the diagnosis of systemic amyloidosis.

Materials/methods

In this study, we describe individual processing steps of SFA specimens, which is easily available biological material for the subtyping of systemic amyloidosis. Additionally, two parameters (P – and D – score) based on the MS/MS count were used to define the existence of amyloid deposits and causative proteins with the greatest abundance. SFA specimens were obtained from five cases with diagnosed amyloidosis and five healthy controls.

Results and conclusions

Three cases of AL λ amyloidosis were correctly subtyped by mass spectrometry-based proteomics analysis. In all cases with systemic amyloidosis we observed presence of serum amyloid P, apolipoprotein A-IV, apolipoprotein A-I and apolipoprotein E proteins. All those proteins are associated with the amyloid formation. Mass spectrometry-based proteomic analysis of SFA offers a powerful tool for typing of systemic amyloidosis.

This work was supported by grants LF_2015_031, AZV_15-31984A and by the National Sustainability Programme (LO1304).