Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Somatic cell hybrid clones were isolated from the fusion of RPC5.4 mouse myeloma cells and B lymphocytes from a patient with common varied agammaglobuinemia. The patient has B lymphocytes that synthesize immunoglobulin but fail to secrete immunoglobulin. The hybrid character of the six clones was established by examination of metaphase chromosome spreads. Most of the hybrid clones expressed mouse and human surface immunoglobulin. All of the clones synthesized immunoglobulin of mouse and human parental origin. Mouse parental immunoglobulin was secreted, whereas the human parental immunoglobulin was not secreted. Human light chain molecules were secreted as part of hybrid H2L2 molecules formed with mouse heavy chains. Human heavy chains had a reduced m.w. in comparison to the mouse heavy chains. Kinetic experiments indicated that human Ig was synthesized in amounts that were comparable to the mouse Ig. Pulse-chase experiments showed that that the intracellular human Ig was removed from the cytoplasm, probably by degradation. These experiments demonstrate that the hybrid cells are an in vitro model of naturally occurring failure of immunoglobulin secretion from agammaglobulinemia. The failure of fusion with mouse myeloma cells to complement the secretion defect suggests that these B cells produce an altered immunoglobulin molecule that is not programmed for secretion.
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PMID:Somatic cell hybrids of mouse myeloma cells and B lymphocytes from a patient with agammaglobulinemia: failure to secrete human immunoglobulin. 10 16

A fraction of ribonucleic acid (RNA) enriched in messenger RNA (mRNA) coding for immunoglobulin G (IgG) was isolated from cells of mouse myeloma RPC5 using specifically purified antibodies to immunoprecipitate polyribosomes engaged in IgG psi heavy and K light chain synthesis. More than 85% of the RNA present consisted of IgG mRNA as determined by an analysis of the products translated in its presence in the wheat germ system. IgG mRNA labeled with 125I was hybridized with mouse liver DNA. Approximately 95% of the RNA hybridized with mouse a Cot 1/2 of 4.0 X 103, indicating that the complementary DNA sequences were present less than five times per haploid genome. In contrast, approximately 75% of poly(adenylic acid) containing RNA prepared from unfractionated polyribosomes of RPC5 cells hybridized with a Cot 1/2 of 3.3 X 103; 25% of such RNA formed hybrids at lower Cot values.
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PMID:Estimation of the number of nucleotide sequences in mouse DNA complementary to messenger RNAs specifying a complete mouse immunoglobulin. 82 62

Chromatin from myeloma cells RPC5 and ABPC22, and from spleen and liver cells of immunized rats and mice, and mice bearing tumours, was fractionated into three part: 0.35 M NaCl-soluble, 2 M NaCl-soluble and residual. The residual fraction from myeloma cells differed from that of immunized spleen cells, described previously as containing unique sequences (5), in that it has higher protein and DNA levels, lower DNase II sensitivity and lower template activity.
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PMID:Differences in salt solubility, DNase II sensitivity and template activity of chromatin from antibody synthesizing spleen cells and myeloma cells RPC 5 and ABPC 22. 689 Jun 25