Related Experiment Videos
[A double monoclonal IgG1-kappa and IgG3-lambda with electrophoretically same mobility in a single patient]
N Miyagawa1, K Morita, H Nakano
1Department of Clinico-Laboratory Diagnostics, Nara Medical University, Kashihara.
Rinsho Byori. the Japanese Journal of Clinical Pathology
|November 1, 1990
Summary
Serum from a patient with abdominal aneurysm contained two distinct monoclonal proteins (MPs) of IgG. These MPs, despite sharing electrophoretic mobility, originated from different B cell clones, as indicated by their unique kappa and lambda light chain profiles and idiotype expression.
Area of Science:
- Immunology
- Protein Chemistry
- Clinical Medicine
Background:
- A 78-year-old male patient with an abdominal aneurysm presented with serum containing monoclonal protein (MP) of immunoglobulin G (IgG).
- Initial immunoelectrophoresis (IEP) and immunofixation electrophoresis (IFE) indicated the MP reacted with both anti-kappa and anti-lambda antisera.
Observation:
- To investigate the presence of both kappa and lambda light chains on a single IgG molecule, MPs were isolated using zone electrophoresis and affinity chromatography.
- Separated MPs were analyzed via immunodiffusion (ID) and IFE.
Findings:
- The kappa-type MP (MP-kappa) was identified as IgG1, while the lambda-type MP (MP-lambda) was identified as IgG3.
- Anti-idiotype antibodies (Aid) against MP-lambda were generated. Subsequent analysis revealed that MP-kappa did not react with Aid, suggesting distinct idiotype expression between MP-kappa and MP-lambda.
Implications:
- These findings demonstrate that two distinct monoclonal proteins, originating from different B cell clones, can exhibit identical electrophoretic mobility.
- This highlights the importance of detailed immunochemical analysis beyond basic electrophoresis for accurate characterization of monoclonal proteins.