Abstract: | A new cell line (KMM-1) was established from a subcutaneous plasmacytoma of a 62-year-old male with multiple myeloma. Immunological studies indicated that cultured cells were derived from the same clone of myeloma cells in vivo: smeared cells were stained with fluoresceinconjugated globulin of antisera monospecific to lambdachain, and lambda-chains in the cell extracts and in culture media were identical to the Bence-Jones protein found in the patient's urine. The cell line grew in suspension with a doubling time of 36-40 h and contained primitive plasmablastoid cells with prominent nucleoli and rough endoplasmic reticulum. Cells had the karyotype of 47, X, -Y. lq+, -2, +t(1:2) (cen:cen), +7, 12q+, 14q+, +mar and carried no Epstein-Barr virus-determined nuclear antigen. Surface markers were as follows; E rosette (-), IgG Fc receptor (-), C3 receptor (-), S-lg (+), TdT (-), asialo-GM, (-). The reasons for the successful establishment of the myeloma cell line are discussed. |