From the Guidelines
Kappa and lambda light chains are proteins that form part of antibodies, which are essential components of the immune system, with each B cell producing antibodies with only one type of light chain, either kappa or lambda, but not both.
Key Points
- Antibodies consist of two heavy chains and two light chains, with the light chains being either kappa or lambda type 1.
- In healthy individuals, the ratio of kappa to lambda light chains in the blood is approximately 2:1.
- These light chains help determine the specificity of antibodies for recognizing and binding to foreign substances or antigens.
- When B cells become cancerous, as in multiple myeloma or other plasma cell disorders, they can overproduce light chains that are released into the bloodstream as free light chains, not attached to complete antibodies.
- Measuring the levels and ratio of free kappa and lambda light chains in serum is clinically important for diagnosing and monitoring conditions like multiple myeloma, amyloidosis, and other plasma cell disorders, as stated in the International Myeloma Working Group Uniform Response Criteria 1.
Clinical Importance
- Abnormal production of light chains can lead to kidney damage and other complications, making their detection and monitoring crucial for patient management.
- The serum free light chain assay can be used for measurement of monoclonal kappa or lambda light chain levels in patients with predominantly light chain monoclonal protein 1.
- The IMWG guidelines provide the specific minimum thresholds for each of the measurable parameters used to assess response in multiple myeloma, including the levels of kappa and lambda light chains 1.
From the Research
Kappa and Lambda Light Chains
- Kappa and lambda light chains are components of immunoglobulins, which are proteins produced by B cells [(2,3,4,5,6)].
- These light chains can be produced in a monoclonal or polyclonal manner, with monoclonal production often associated with diseases such as multiple myeloma and AL amyloidosis [(2,3,5)].
- The ratio of kappa to lambda light chains can vary, with some studies reporting a ratio of 43:33 in patients with multiple myeloma 4.
- Kappa and lambda light chains can be detected in serum using various methods, including enzyme-linked immunosorbent assay (ELISA) and immunoturbidimetric assay [(3,5)].
Clinical Significance
- The type of light chain production (kappa or lambda) can have clinical and prognostic significance in patients with multiple myeloma 4.
- Patients with lambda light chain production may have a poorer prognosis and shorter survival rate compared to those with kappa light chain production 4.
- Free kappa and lambda light chains can also play a role in the pathogenesis of inflammatory diseases, such as inflammatory bowel disease and renal diseases 6.
Detection and Measurement
- Monoclonal antibodies can be used to specifically recognize and measure kappa and lambda free light chains in serum 3.
- These antibodies can also be used to immunostain monoclonal FLC-producing plasma cells and pathologic light chain-related amyloid and nonfibrillar tissue deposits 3.
- The measurement of free kappa and lambda light chains can be useful in the diagnosis and management of light chain-associated diseases [(3,5)].