Myeloma protein

If a reduction in myeloma protein is not seen on one chemotherapy regimen, another regimen should be used. 

Figure 3.25 Starch gel electrophoresis of human serum proteins. Samples 1 and 2 are normal while samples 3, 4 and 5 show an extra band adjacent to the normal albumin which is due to the presence of bis-albumin. Sample 7 contains a myeloma protein that has remained near the origin. (Photograph by permission of Dr D. Brocklehurst, Department of Clinical Chemistry, Doncaster Royal Infirmary, UK.)...

Acetyluracil can cause the production of certain pyrimidine-specific antibodies [306]. This interesting activity is responsible for the antibody precipitation of some mouse myeloma proteins [307]. 

Recently, polyclonal mouse antihuman IgG antibodies fluorescently labeled with Cy5 were used to detect the binding of human myeloma proteins to biotinylated monoclonal antibodies. Again, Cy5-labeled antibodies were used to determine bacterial, viral, and protein antigens bound to biotinylated IgGs. 

Affinity adsorbents having carbohydrate ligands have been used for the isolation and purification of many types of macromolecular substances. To illustrate, several types of antibodies, enzymes, lectins, and myeloma proteins have been obtained in highly purified form. All of the substances that have been purified by this procedure exhibit specificity for a particular carbohydrate moiety. It is the purpose of this article to assemble information on the methods for preparing affinity adsorbents having carbohydrate ligands, and to illustrate the use of these adsorbents for the purification of representative, macromolecular substances. 

Myeloma proteins occur in animal tumors of various types. The synthesis of these proteins can be induced in some experimental animals by injection of mineral oil, or the implantation of plastic discs.161 Myeloma proteins were shown to possess antibody activity, with specificity for different types of substances.161 Some of these proteins were found to combine with such carbohydrates as bacterial, cell-wall polysaccharides, lipopolysaccharides, dextrans, levans, and galactans.162 Myeloma proteins that combine with galactans or dextrans possess anti-galactan activity,163,164 or anti-dextran activity,165-167 and have been studied most extensively. 

Fig. 8.—Elution Patterns for Mouse-myeloma Proteins and Rabbit Anti-Glc-BSA Serum from Isomaltosyl-agarose. [Elution with 1% isomaltose (IsoGUcj) solution in (A) and with 10% D-glucose (Glc) solution in (B) in 0.02 M phosphate buffer, pH 7.2, in saline (see Ref. 17).]...

Agar-diffusion tests with the anti-isomaltose, myeloma protein and several dextran preparations showed that the protein does indeed combine with a number of dextrans. Results of gel electrophoresis of the sample showed that the purified myeloma protein consisted of several multimolecular forms.107 This observation is at variance with a report that the W3129 myeloma protein isolated from the same type of serum was homogeneous.168 Additional studies are needed in order to establish whether the anti-isomaltose, myeloma protein is synthesized as a homogeneous protein or in multimolecular form. 

The Binding Constants of a Number of Derivatives of D-Galactose with Two IgA Myeloma Proteins Having Anti-galaetan Specificity"... 

For three other myeloma proteins having anti-(l — 6)-a-D-glucopyranan specificity (W 3129, W 3434, and QUPC 52), the authors found a somewhat different pattern of cross-reactivity.63 The reaction of W 3129 with its anti-idiotypic antibody was not totally inhibitable by even high concentrations of W 3434 protein, and not at all by protein QUPC 52. Thus, proteins W 3129 and W 3434 share some determinants, but are clearly different from each other and from QUPC 52. 

Eleven IgA myeloma proteins that precipitate with Pneumococcus C polysaccharide (PnC) have been described.65-69 This antigen has a structure whose general features are known,70 71 and it is a somatic, species-specific polysaccharide. 

Association constants between a number of these anti-PnC myeloma proteins and phosphorylcholine have been determined79 by equilibrium dialysis and found to range from 104 to 105 liter.moL. Values of K obtained by fluorescence titration have been found to be in close agreement.80,81... 

Lundblad, A., Steller, R., Kabat, E A, Hirst, J. W., Weigert, M. G., and Cohn, M. (1972) Immunochemical studies on mouse myeloma proteins with specificity for dextran or for levan. Immunochemistry 9, 535—544. 

Fig. 39.—Structure of Glycan IA-1 of Human, IgM Myeloma Protein.116,117 [Other glycans are derived from glycan IA-1 by the absence of the following mannose residues IA-2, residue 1 IA-3, residues 1 and 6 IB-1, residues 1, 2 and 6 IB-2, residues 1, 2, 4, and 6 IIA, residue 4 II, residues 1 and 4 and IIB, residues 1, 4, and 6.]...

An immunoadsorbent has been prepared by attaching BSA, containing p-diazophenyl l-thio-/3-D-galactopyranosides, to cyanogen bromide-activated Sepharose.175 This affinity material was used to isolate mouse immunoglobulins (myeloma proteins) that bound carbohydrate.178... 

Early evidence pointing to a restriction in immunoglobulin expression was the demonstration that, in individuals who are heterozygous for allotype, myeloma proteins carry one or the other, but never both, of the allelic determinants found in the pooled immunoglobulin of that person (M rtensson, 1961 Harboe et al., 1962). This finding was interpreted to indicate that the alternate allotypic determinants are present on different immunoglobulin molecules, which are produced by different cells. Oudin (1960) had observed a presumably related phenomenon in rabbits. 

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