Studies of four new human myeloma cell lines.

We describe the establishment and studies of four myeloma cell lines that were derived from 2 young individuals with plasma cell leukaemia (Karpas 25 and 1272) and from 2 older persons with multiple myeloma (Karpas 417 and 929). The cultured cells have the ultrastructural appearance of plasma cells with abundant rough endoplasmic reticulum (RER). Their phenotypic profile conform with that of malignant plasma cells. Karyotype analysis revealed that each cell line is unique and all are hyperdipoide with complex aberrant chromosomes. FISH analysis revealed cryptic translocations affecting the IGH locus in 14q32 of 2 of these cell lines. Using R- and G-banding numerous other chromosomal abnormalities were recorded and illustrated in each of the 4 cell lines.