![]() Unexplained hypogammaglobulinaemia: This is a rare indication as usually low globulin concentrations can be linked to lack of synthesis due to hepatic insufficiency, or loss due to haemorrhage or protein-losing enteropathies. Persistent unexplained increase in globulins: the electrophoretogram will demonstrate an increase in one of the fractions, which may help to guide further diagnostics.Ĥ. This is called monoclonal gammopathy and is supportive for the diagnosis of multiple myeloma.įigure 2: Electrophoretogram showing the appearance of a monoclonal peak in the gamma area.ģ. All of these identical proteins will migrate to the same area on the electrophoresis gel, resulting in a high narrow-based peak in either the beta-2 or gamma area (Figure 2). Normal plasma cells produce a wide variety of immunoglobulins, but neoplastic plasma cells in multiple myeloma produce only one, or sometimes two types (or clones). These patients will generally also have a hyperglobulinaemia (based on routine clinical chemistry testing) but can present with normoglobulinaemia. Clinical suspicion of multiple myeloma, based on the presence of bone pain, lytic bone lesions, proteinuria and/or hypercalcaemia. SPE is necessary to determine albumin concentrations accurately in these species.Ģ. Determination of albumin in some exotic species: the assay (bromocresol green reaction) used to measure albumin on veterinary chemistry analysers is not accurate in rabbits (falsely high), birds (falsely low) and some new world monkeys (falsely high). SPE is indicated in the following scenarios: 1,2ġ. It is also important to remember that each fraction contains many different proteins of similar but not identical charge and size – this is why the fractions have broad bases. It should be noted that SPE is not a direct measurement of the concentrations of different proteins, although it is a fairly accurate estimate. SPE can be used to give an indication of which groups of proteins are increased or decreased, but does not generally help to identify changes in specific proteins. Specific proteins migrate to certain fractions based on their charge and size It has been determined (through proteomic studies using other methods), which major proteins are found in each fraction, as illustrated below in Figure 1.įigure 1: SPE tracing showing the different fractions. The fractions, apart from albumin, have traditionally been allocated a Greek letter and a number – alpha-1, alpha-2, beta-1, beta-2 and gamma. This percentage is calculated by a computer programme, and is multiplied by the total protein concentration to give the concentration of each fraction. ![]() Each curve/ fraction represents a percentage of all protein present in serum. The gel is then placed into a scanner, which converts the density of each band into curves, which appear as the typical fractions of the electrophoretogram (Figure 1). A stain is applied to the gel, making the bands visible. This results in a separation of all the proteins into bands. The more negatively charged proteins migrate through the gel to the cathode (positive charge) and the more positively charged proteins, to the anode (negative charge). A serum sample is placed into the gel, and an electrical current is applied across it. The gel provides a 3-D matrix with large pores (compared to the size of proteins). The most common method uses agarose gel as a platform. Serum protein electrophoresis (SPE) separates proteins based on their size and charge. Albumin, for example, is the most negatively charged protein, while immunoglobulins have a slight positive charge. Serum proteins come in different shapes and sizes, and also have different charges. Dr Emma Hooijberg BVSc GPCert (SAP) DipECVCPĭepartment of Companion Animal Clinical Studies, University of How does this method work?
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |