Ectopic expression of A-Myb rescues WEHI 231 cells from anti-IgM–induced cell cycle arrest and apoptosis.

(A) Cultures of clones S3, S5, pAW1, pAW4, pAW5, pAW8, and pAW9 were incubated, in triplicate, for 48 hours in the presence of 2 μg/mL anti-IgM antibody or medium alone as control. Cell proliferation was quantitated by conversion of MTS dye to its formazan product. Data are plotted as the percentage of converted formazan by anti-IgM–treated cells relative to that of control cells. (B) S3, S5 PAW5 and pAW9 cells were incubated, in triplicate, for 24 or 48 hours in medium or with 2 μg anti-IgM (αIgM) and cell viability was determined by trypan blue exclusion assay. Trypan blue positive cell numbers are plotted as a percentage of the total cell number. The mean and SD are representative of 2 independent experiments carried out in triplicate.