Biology of the human myeloma cell population. I.Macromolecular characteristics.

Several human myeloma cell populations were studied using a combination of cytochemical (Unna-Pappenheim and naphthol yellow staining, Feulgen reaction) and autoradiographical (uridine, leucine, thymidine uptake and actinomycin binding) techniques. Progressive differentiation of the myeloma population was associated with: 1. a loss of proliferative activity, 2. decreased transcriptional capacity, 3. decreased RNA and protein synthesis, 4. increased RNA and protein concentrations, 5. greater stability of the protein synthesis template. The existence of a pre-myelomatous compartment is suggested in the light of these results and those of previous kinetic studies in vivo.