Author(s)

Lun Xia ¹, Yi Zhang ¹

Affiliation(s)

¹ College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, 410128, Hunan, China

Corresponding Author

Yi Zhang

ABSTRACT

Free light chains are low-molecular-weight protein byproducts released by plasma cells during the synthesis of immunoglobulin. Under normal physiological conditions, serum-free light chain concentrations are maintained at low levels; however, they increase markedly in diverse pathological states, especially in cases of abnormal proliferation of plasma cells. This review systematically outlines the evolution of methodologies for detecting free light chains, from traditional electrophoresis and immunofixation to modern quantitative techniques such as mass spectrometry, the Freelite test, enzyme-linked immunosorbent assay, and particle-enhanced turbidimetric immunoassay. It critically evaluates the principles, analytical performance, and clinical applicability of each method. Beyond multiple myeloma, the article also explores the growing significance of free light chains in a broad spectrum of conditions, including autoimmune diseases, acute allergy, viral infection, multiple sclerosis, and chronic kidney disease. The expanding clinical utility of free light chains as biomarkers for diagnosis and monitoring underscores their indispensable role in modern laboratory medicine and personalized patient care.

KEYWORDS

Free light chains, Detection methods, Immunoassay, Multiple myeloma, Biomarkers

CITE THIS PAPER

Lun Xia, Yi Zhang. Development of detection methodologies for free light chains and their applications in clinical practice: A review. Social Medicine and Health Management (2026). Vol. 7, No.1, 108-115. DOI: http://dx.doi.org/10.23977/socmhm.2026.070115.

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