Myeloma leucine

The remarkable similarity in the molar ratios of the amino acids offers encouragement to the proposition that common peptides will be found in the electrophoretic components of the serum proteins. The peptide of spot 7 probably differs from spot 8 in leucine content, which would account for the higher Rf of spot 8. More encouraging are the recent reports of Edelman (2, 13) who found that gamma-globulin, the Bence-Jones proteins, and the myeloma proteins have a peptide unit of common amino acid composition. 

Optimal conditions for the quantitation of incorporation of [ H]leucine into immunoglobulin by bone marrow cells of patients with multiple myeloma has been reported. ... 

As mentioned above, the mouse myeloma cells studied by Uhr s group incorporate radioactive carbohydrate almost exclusively into IgG when radioactive leucine is used as a label, 50% of the intracellular protein-bound radioactivity and all of the secreted protein-bound label is due to IgG (Zagury et al., 1970). Radioautographic studies using the electron microscope were therefore performed on mouse myeloma cells at various times after labeling with tritiated leucine, galactose, and glucosamine, re-... 

---