Immunoelectrophoresis is used for laboratory diagnostic detection of monoclonal antibodies in a patient’s blood. Monoclonal antibodies are derived from the same cell and are directed against the same antigens. For this reason, they are considered pathologic and, when detected, are suggestive of diseases such as Waldenström disease.
What is immunoelectrophoresis?
Immunoelectrophoresis is used for laboratory diagnostic detection of monoclonal antibodies in a patient’s blood. Ions have differential mobility. This differential mobility forms the basis of electropheresis methods. These methods separate different substances from each other using electric fields and gravity. One well-known method from the field is immunoelectropheresis. This is a qualitative diagnostic procedure used to detect monoclonal antibodies. Antibodies are immunologically active protein substances of a specific cell line. Monoclonal antibodies all originate from the same B lymphocyte and are accordingly directed against a single epitope. Any natural immune response against invading antigens corresponds to a polyclonal response and is thus directed against different epitopes. A monoclonal immune response therefore provides evidence of pathological body processes. Monoclonal antibodies bind different molecules with high specificity. This binding can be detected by immunoelectrophoresis. The method is a qualitative laboratory diagnostic procedure and is composed of the two types of procedures, serum electrophoresis and immunodiffusion.
Function, effect, and objectives
Immunoelectrophoresis combines the methodology of serum electrophoresis with immunodiffusion. The patient’s serum is placed on an agarose gel or cellulose acetate film. A control serum is also applied. The application is followed by electrophoretic separation of the samples. Antisera, IgG, IgA, IgM, acetic acid for normal electrophoresis and kappa, and lambda are applied between the separation lines. This sets up a reaction with the antibodies of the patient serum, which generates precipitation lines. Depending on the antiserum used and the position and shape of the individual lines, conclusions can be drawn about the immunoglobulins with kappa or lambda light chains contained. In the case of a lambda band, free light chains of antibodies are present. Using the rare IgE and IgD, the laboratory provides additional evidence that allows precise determination of the immunoglobulins. A procedure of immunodiffusion electrophoresis takes place according to Pierre Grabar and Curtis Williams and corresponds to a combination of agarose gel electrophoresis of proteins and an antibody diffusion. First, agarose gel electrophoresis takes place. Subsequently, the contained antibodies diffuse against the bands of antigens and thereby give rise to precipitate arcs. This should be distinguished from Laurell’s Rocket immunoelectrophoresis, which corresponds to electrophoresis of proteins within an agarose gel, each of which contains antibodies at a specific concentration. The gel contains a slightly basic buffer that allows only the antigens to migrate, pushing most of the antibodies to the isoelectric point by exposure to the slightly basic pH until they stop moving electrophoretically. At the beginning of a Rocket immunoelectrophoresis, there is an excess of antigen, so soluble antigen-antibody complexes are formed. During electrophoresis, additional binding occurs between antigens and additional antibodies. At the equivalence point, immunoprecipitates are formed in this way, resembling rocket-like figures with a height proportional to the antigen concentration. The height of the precipitate is measured to evaluate the assay.
Risks, side effects, and hazards
The detection of monoclonal antibodies is particularly important for the diagnosis of multiple myeloma and Waldenstrom’s disease. The detection obtained is indicative of a malignant degeneration of immune cells. Multiple myeloma corresponds to a cancer of the bone marrow characterized by the malignant proliferation of antibody-producing cells in the plasma. These plasma cells produce antibodies and their fragments. Malignant plasma cells always originate from a common progenitor cell and are thus genetically identical. They produce monoclonal antibodies exclusively.The malignancy of this disease may correspond to a precancerous stage, but may also reach a highly malignant stage that is rapidly lethal without treatment. Disease symptoms result from the malignant growth of the cells or from the antibodies and antibody fragments. The most common symptoms include bone pain, bone dissolution, and spontaneous bone fractures. Calcium levels in the blood are often elevated. In addition, the abnormal antibodies often lodge in the tissues and cause organ dysfunction, which can lead to manifestations such as kidney failure or impaired blood flow. Waldström’s disease is also a malignant tumor disease. More specifically, it is a malignant lymphoma disease that is classified as a slowly progressive and nearly asymptomatic B-cell non-Hodgkin’s lymphoma. In most cases, abnormal productions of monoclonal IgM can be detected in the disease, which are due to activities of the malignant lymphoma cells. Waldenström’s disease is extremely similar to multiple myeloma in its characteristics, but usually shows a more favorable course. Most patients with Waldenström disease are largely asymptomatic until diagnosis. Other patients show early symptoms such as nonspecific fatigue or peripheral neuropathies resulting from the deposition of monoclonal IgM within the myelin sheath. Even small amounts of IgM can cause polyneuropathy. In other patients, polyneuropathy does not occur even with high levels. In addition, nonspecific symptoms such as fever, unwanted weight loss, or night sweats may occur. Bone pain is also characteristic. Due to the overproduction of IgM, the blood becomes hyperviscous, so that the above symptoms may be associated with those of a hyperviscosity syndrome. This bleeding tendency manifests itself in most cases in frequent nosebleeds, headaches, a general feeling of malaise or blurred vision and acoustic complaints. To detect malignancies of this type, immunoelectropheresis has long become a standard diagnostic procedure.
