Polyclonal free light chains: promising new biomarkers in inflammatory disease

Abstract

In this review, we explore potential novel roles of polyclonal free light chains (FLCs) as a biomarker of disease processes and predictor of mortality in different patient populations. In recent years, there have been many publications demonstrating raised polyclonal FLCs in several inflammatory and infective diseases. However, the potential utility of FLCs as a clinical biomarker remains an area of debate. We review the current evidence, and establish whether certain key criteria to fulfill the role of a useful biomarker have been satisfied. In addition, we also consider the potential role of FLCs in the pathophysiology of inflammatory disease and address the concepts of FLCs as both a therapeutic target and potential therapeutic agent.