ALL cell expansion in suspension culture. The proliferative capacity of ALL cells from 47 patients was evaluated in suspension culture (SC). Cells from 40 patients were maintained in the culture system for at least 4 weeks, and expansion of cell numbers was observed in 28 of these 40 cases. The graph depicts the proliferation observed in the 28 cases and that observed using cells from 10 NBM donors. Proliferation of cells from both pre-B and c-ALL subtypes was observed, and there was no correlation between proliferation, prognostic indicators, or diagnostic and relapse samples. Data are expressed as means ± standard error.