Vitro drug-induced apoptosis in freshly isolated leukemic cells: a flow cytometric analysis.

Fludarabine is considered a useful drug in the management of B-CLL resistant to conventional chemotherapy as it is able to trigger apoptosis in neoplastic B cells. In order to analyze this aspect, we tested by means of a simple and rapid flow cytometric method the in vitro apoptotic response of CD5+ B-CLL lymphocytes to FAMP, in comparison with other cytoreductive agents such as Interferons. Our findings showed that apoptosis occurred significantly in lymphocytes cultured with FAMP, but not with IFNs. In conclusion, flow cytometry allows an easy and rapid detection of in vitro drug-induced apoptosis, possibly representing also a reliable assay for testing tumor cell sensitivity or resistance.