Abstract
In July 2004 we have established an in vitro method for culturing and expansion of human primary myeloma cells in a cytokine free system. This method which was designed to optimize the cell signaling between myeloma cells and their stromal support is easilly reproducible and so far has been applied successfully in 15 of 15 myeloma patients. This progress allows, for the first time, long term maintenance and expansion of the tumor cells with day by day observation of how the myeloma clone propagates, as assessed by morphology, FACS analysis and by the FISH-Bioview system (see figures 1,2 showing a group of myeloma cells after 28 days in culture along with their single FISH signal for known del13q).
The protocol is currently under intensive procedure of standardization for general use.
Applications of this culture system have already yielded several new findings. One, relating to the peculiar nuclear changes appearing in myeloma cells during culture is being presented in detail in another abstract. An additional issue is the ability to manipulate the culture to detect very small numbers of myeloma cells in the range of MRD. Yet another use is in vitro drug assay. Preliminary results have revealed no apparent influence of pamidronate or erythropoietin on myeloma cell expansion up to 28 days in co-culture (4 cases). In contrast, thalidomide and simvastatin had deleterious effect on the stromal support (3 cases) but the former did not eliminate the myeloma cells whereas no myeloma cells were seen with simvastatin after 3–7 days in culture.
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