Monoclonal Immunoglobulin (Ig)

What sample is needed for Monoclonal Immunoglobulin (Ig)?

1. IFE (Immunofixation electrophoresis) can be done on the patient’s serum.
2. Other fluids include CSF, urine, and biological fluids.
3. Collect 24 hours of urine according to the instructions.
4. Store the sample at 2 to 8 °C for 5 days.

What are the precautions for Monoclonal Immunoglobulin (Ig)?

1. Fresh serum is the sample choice.
2. The fasting sample is preferred.
3. Avoid anticoagulant use.
4. Centrifuge the sample immediately for 15 minutes.

What are the indications for Monoclonal Immunoglobulin (Ig)?

1. To identify monoclonal gammopathy.
2. To monitor treatment of monoclonal gammopathy.
3. To find the light chains / heavy chains of immunoglobulin in the urine.
4. Monoclonal gammopathy of undetermined significance (MGUS).
5. Waldenström’s macroglobulinemia.
6. Multiple Myeloma (used for more than 100 years).
7. Amyloidosis.

How will you define monoclonal immunoglobulin(Ig)?

1. It is a so-called monoclonal gammopathy: a spike-like M-protein and paraprotein.
2. It is located in the γ-region and, less frequently, in the β-region. Rarely seen in the α2-region.
3. Most people with monoclonal spikes have myeloma.
4. Other minorities with monoclonal gammopathy are:
   1. Waldenström’s macroglobulinemia.
   2. Secondary monoclonal gammopathy.
   3. Idiopathic monoclonal gammopathy.
5. Monoclonal gammopathies are clonal disorders of atypical B-lymphocytes.  Monoclonal gammopathy is a homogeneous product of a single clone of proliferating cells that secretes a single homogeneous immunoglobulin (Ig) or its fragments.
6. These monoclonal gammopathies are a clonal disorder of B-lymphocyte proliferation.
7. These atypical B-lymphocytes are single clones of proliferating cells that will produce a single immunoglobulin (Ig) or its fragments.
8. This abnormal monoclonal immunoglobulin (Ig) has two heavy chains (γ α and μ) in the serum, CSF, and urine. The light chains are either κ or λ and are present in the serum, CSF, and urine.

What are the bands of monoclonal gammopathy?

1. The majority have monoclonal bands due to multiple myeloma.
2. Waldenström’s macroglobulinemia.
3. Secondary monoclonal gammopathies.
4. Idiopathic monoclonal gammopathy.

How would you discuss the pathophysiology of Monoclonal Immunoglobulin (Ig)?

1. Immunofixation electrophoresis studies differentiate protein antigens and their split products and are used to evaluate myeloma.
2. This was described in 1964.
3. Immunofixation electrophoresis is replacing electrophoresis because it is faster and easier to interpret.
   1. The principle is the same in both processes.
4. Monoclonal immunoglobulin (Ig) consists of heavy and light chains.
   1. These are purified antibodies cloned from a single cell.
   2. These antibodies will bind to surface antigens.
   3. Producing monoclonal antibodies in animals takes 3 to 6 months.
5. Only heavy chains are produced in heavy chain diseases, while only light chains are produced in light chain diseases.
6. IFE identifies monoclonal Ig and light chains or heavy chains.
7. By electrophoresis, there is a spike of monoclonal Ig (Antibody).

1. Waldenström’s macroglobulinemia also shows a monoclonal spike.
2. Both diseases above give light chain excretion in the urine.
3. IFE can also find that the spike is due to a light chain or heavy chain.
4. Chronic diseases produce polyclonal bands of these immunoglobulins.
5. Non-malignant monoclonal immunoglobulin is seen in:
   1. 5% of people over the age of 75 years of age.
   2. These are lower in concentration than the malignant bands.

What is the Procedure and Principle of Immunofixation Electrophoresis (IFE)?

1. This IFE is a two-stage procedure:
   1. Agarose gel protein electrophoresis (IEF).
   2. Immunoprecipitation.
2. The patient’s sample is placed in six separate wells on the agarose gel, and electrophoresis separates the major protein groups.
3. One track is treated with a chemical fixation solution to fix all proteins in the agarose and create an electrophoresis reference pattern for the specimen.
4. The other five tracks are treated with heavy- and light-chain antisera, which react with individual immunoglobulins in the specimen, causing them to Immunoprecipitate.
5. Fix in the agarose.
6. All unreacted proteins are washed from those five tracks out of the gel.
7. Now, all 6 tracks are stained to visualize the fixed protein bands.

What is the normal Monoclonal Immunoglobulin (Ig)?

• No monoclonal band is identified.

What are the causes of seeing monoclonal bands?

1. Multiple myeloma shows in 99% of patients in serum and urine.

2. Waldenstrom macroglobulinemia always shows a serum IgM-type monoclonal band.
3. Monoclonal light chains, also called κ or Bence Jones protein, are seen in the urine of Multiple myeloma cases in 75 % of the patients.
4. Waldenstrom macroglobulinemia also shows light chains in the urine in 75 % of the patients.
5. Amyloidosis can be seen in the urine through the light or heavy chain.

What are the signs and symptoms of Multiple Myeloma?

1. Weakness and fatigue.
2. Weakness in the legs.
3. Nausea and vomiting.
4. Recurrent infections.
5. Bone pain in the back or ribs.
6. H/O fracture

What are the conditions where you will see Polyclonal bands?

1. Chronic infections.
2. Autoimmune diseases.
3. Chronic liver diseases.
4. Amyloidosis.

What are the causes of the Monoclonal Ig band in the urine?

1. Multiple myeloma.
2. Waldenström macroglobulinemia.

How will you diagnose monoclonal gammopathy?

1. Bone marrow plasma cells are >10% of the total cells.
2. Monoclonal protein in the serum or urine.
3. Evidence of end-organ diseases like:
   1. Anemia.
   2. Bone lesions.
   3. Hypercalcemia.
   4. Renal diseases.

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