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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1983-8-17
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pubmed:abstractText |
The discovery of a human myeloma protein comprising a kappa L-chain with an increased mol. wt of 30,000) (Bouvet et. al., 1980) prompted investigations on the incidence of such heavier L-chains among other human myeloma proteins. In 105 samples examined, 34 were found to have L-chains heavier than normal (23,000-24,000), ranging from 25,000 up to 31,000, and five of lighter mol. wt (21,000-22,000). These mol. wt abnormalities were detected by electrophoresis in sodium dodecyl sulfate 10% polyacrylamide gels (SDS-PAGE) after reduction with 2-mercaptoethanol. The mol. wt of three of the heavier kappa or lambda chains was also estimated by filtration through a Sephadex G100 column and by sedimentation equilibrium. All three methods indicated a mol. wt increase of about 15-25% as compared with the usual mol. wt. The distribution of the high mol. wt chains among all L-chains examined was found to be 11 out of 62 kappa chains (17.7%) and 23 out of 43 lambda chains (53%) (P less than 0.001). A preferential association of such L-chains with H-chains producing multiple bands in SDS-PAGE (P less than 0.01) and an association between multiple L-chain and multiple H-chain band (P less than 0.05) were also observed. In contrast, no abnormal L-chain was found in immunoglobulins from normal subjects. Spontaneous degradation of the normal H-chains sometimes yielded fragments of 30,000 mol. wt. These fragments were easily distinguishable from abnormal L-chains. The nature of extra mol. wt in heavy L-chains was investigated for the presence of carbohydrate moiety. Four large and three normal size L-chains were examined for amino-sugar and sialic acid content. A small amount (one residue per molecule) of amino-sugar was detected only in two normal and two heavy L-chains, whereas sialic acid was only found in the heaviest (27,000-30,000) L-chains (Lh) and in small percentage (one or two residues per molecule). Total sugar estimation in one Lh chain indicated a proportion not exceeding three or four residues per L-chain (mol. wt 1,000) and this is insufficient to explain the 15-25% (3,600-6,000) mol. wt increase. It is therefore possible that, at least in some heavy myeloma L-chains, an additional peptide is expressed. Whatever the nature of the increase it would be of interest to elucidate whether this is a marker of malignant process or of an intermediate step of normal Ig synthesis.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Carbohydrates,
http://linkedlifedata.com/resource/pubmed/chemical/Immunoglobulin G,
http://linkedlifedata.com/resource/pubmed/chemical/Immunoglobulin Heavy Chains,
http://linkedlifedata.com/resource/pubmed/chemical/Immunoglobulin Light Chains,
http://linkedlifedata.com/resource/pubmed/chemical/Immunoglobulin lambda-Chains,
http://linkedlifedata.com/resource/pubmed/chemical/Myeloma Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Peptides
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pubmed:status |
MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
0161-5890
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
20
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
397-407
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:6408400-Carbohydrates,
pubmed-meshheading:6408400-Electrophoresis, Polyacrylamide Gel,
pubmed-meshheading:6408400-Humans,
pubmed-meshheading:6408400-Immunoglobulin G,
pubmed-meshheading:6408400-Immunoglobulin Heavy Chains,
pubmed-meshheading:6408400-Immunoglobulin Light Chains,
pubmed-meshheading:6408400-Immunoglobulin lambda-Chains,
pubmed-meshheading:6408400-Molecular Weight,
pubmed-meshheading:6408400-Myeloma Proteins,
pubmed-meshheading:6408400-Peptides
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pubmed:year |
1983
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pubmed:articleTitle |
Human myeloma light chains with increased molecular weight: high frequency among lambda chains.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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