Figure 2.

Induction of apoptosis in MLMA cells mediated by CD20 and B-cell antigen receptor. (a) MLMA cells were treated with either rabbit anti-μ heavy-chain polyclonal antibody (αμ, 10 μg/ml) or a combination of anti-CD20 monoclonal antibody (mAb; αCD20, 5 μg/ml) and secondary rabbit anti-mouse immunoglobulin antibody (RαM, 5 μg/ml) for 48 hr and binding with fluorescein iosthiocyanate (FITC)-conjugated annexin V was examined by flow cytometry. Each experiment was performed in triplicate and the means + SD are indicated. (b) The same sample preparations as in (a) were cytocentrifuged and morphological appearance was examined by Giemsa-staining and nuclear staining with DAPI, using light microscopy and confocal microscopy, respectively. (c) Cell lysates were obtained from the same sample preparation as in (a) and the proforms of each caspase, cleaved caspase-3 and cleaved PARP were detected by immunoblotting.