Serum and Tissue Light-Chains as Disease Biomarkers in AL Amyloidosis

Amyloid light-chain (AL) amyloidosis is the most prevalent type of diagnosed systemic amyloidosis in Western countries, characterized by the deposition of misfolded immunoglobulin light chains (LCs) in various organs, most commonly the heart and kidneys. Circulating free LC (FLC) measurement, which can be performed by mass spectrometry or antibody-based techniques, is a crucial tool for AL amyloidosis diagnosis, risk assessment, and management. Additionally, diagnosing AL amyloidosis requires accurate detection of LC deposits in tissues. In addition to immunohistochemical techniques, mass spectrometry-based methods are now available.