Preparation of highly purified human IgG, IgM, and IgA for immunization and immunoanalysis

Solving many immunological problems we need highly purified immunoglobulin prepara tions. First of all, IgG and their Fc fragments, IgM, IgA, IgE, IgD, immunoglobulin λ and κ chains are widely used as immunogens. On the other hand, these biomolecules are necessary to obtain immunosorbent for the binding of cross reactive antibodies; they are also needed for the affinity chromatography purification of anti immunoglobulin antibodies from polyclonal sera. Purified immunoglobulin preparations serve often as standard ones; they are also nec essary for evaluation of specific immune sera. The immunoglobulin purification is the first step for the obtaining of standard antibodies and conjugates including them. The use of highly purified antibodies leads to decreased back ground values in immunoenzyme analysis [1—4]. Numerous approaches of molecular immunol ogy and biochemistry are well known for immunoglobulin isolation and purification. They all are based on the information about physico chemical and biological properties of molecules belonging to this group (see Table 1). For isolation and separation of these molecules, their molecu lar masses, isoelectric points, solubility under different conditions as well as their affinity to some substances (bacterial A and G proteins) must be taken into consideration [4—6]. Gel chromatography, affinity chromatogra phy and ion exchange chromatography, dialy sis, precipitation by salts and organic solvents are based on different properties of immuno globulin molecules. The most widely used proto cols described [2, 4, 6, 7] combine several approaches. However, a lot of them are not clear and lack adequate assays to control the immu noglobulin purity. Human IgG isolation and purification are based on affinity chromatography with A and G protein columns; they are well described in the literature, their results are reliable, and we suppose these approaches need no further Preparation of highly purified human IgG, IgM, and IgA for immunization and immunoanalysis