Immunoglobulin production and secretion in Bence Jones protein myeloma and "nonsecretory" myeloma. Ultrastructural and immunofluorescence study.

Using our electron microscopic method for polysome analysis and an immunofluorescent technique we studied Ig production and secretion by tumor cells in seven BJP myeloma patients and seven "nonsecretory" myeloma patients. In BJP myeloma Ig production and secretion is of three types: Type 1, only L-chains are synthesized and secreted; Type 2, the myeloma cells show fluorescence for H-chains, but upon polysome analysis there is no peak at polysomes corresponding H-chain production; Type 3, the myeloma cells show fluorescence for H-chains, and polysome analysis shows two peaks corresponding to L- and H-chain production. Polysome analysis of "nonsecretory myelomas show the presence of only very few membrane-bound polysomes and their distribution curves are entirely different from those of "ordinary" myeloma. Furthermore, the distribution patterns vary among seven cases. Results obtained by polysome analysis and immunofluorescent technique suggest that the "nonsecretory" myeloma could be divided into several subtypes.