TY - JOUR
T1 - CD40 stimulation sensitizes CLL cells to lysosomal cell death induction by type II anti-CD20 mAb GA101
AU - Jak, Margot
AU - van Bochove, Gregor G. W.
AU - Reits, Eric A.
AU - Kallemeijn, Wouter W.
AU - Tromp, Jacqueline M.
AU - Umana, Pablo
AU - Klein, Christian
AU - van Lier, Rene A. W.
AU - van Oers, Marinus H. J.
AU - Eldering, Eric
PY - 2011
Y1 - 2011
N2 - Sensitivity of chronic lymphocytic leukemia (CLL) cells to anti-CD20 mAbs is low and, therefore, the efficacy of monotherapy with current anti-CD20 mAbs is limited. At present, it is not known whether sensitivity of CLL cells to CD20 mAbs is modulated by microenvironmental stimuli. We have shown previously that in vitro CD40 stimulation of peripheral blood-derived CLL cells results in resistance to cytotoxic drugs. In the present study, we show that, in contrast, CD40 stimulation sensitizes CLL cells to the recently described novel type II anti-CD20 mAb GA101. Cell death occurred without cross-linking of GA101 and involved a lysosome-dependent mechanism. Combining GA101 with various cytotoxic drugs resulted in additive cell death, not only in CD40-stimulated CLL cells, but also in p53-dysfunctional CLL cells. Our findings indicate that GA101 has efficacy against chemoresistant CLL, and provide a rationale for combining cytotoxic drugs with anti-CD20 mAbs
AB - Sensitivity of chronic lymphocytic leukemia (CLL) cells to anti-CD20 mAbs is low and, therefore, the efficacy of monotherapy with current anti-CD20 mAbs is limited. At present, it is not known whether sensitivity of CLL cells to CD20 mAbs is modulated by microenvironmental stimuli. We have shown previously that in vitro CD40 stimulation of peripheral blood-derived CLL cells results in resistance to cytotoxic drugs. In the present study, we show that, in contrast, CD40 stimulation sensitizes CLL cells to the recently described novel type II anti-CD20 mAb GA101. Cell death occurred without cross-linking of GA101 and involved a lysosome-dependent mechanism. Combining GA101 with various cytotoxic drugs resulted in additive cell death, not only in CD40-stimulated CLL cells, but also in p53-dysfunctional CLL cells. Our findings indicate that GA101 has efficacy against chemoresistant CLL, and provide a rationale for combining cytotoxic drugs with anti-CD20 mAbs
U2 - https://doi.org/10.1182/blood-2011-01-331702
DO - https://doi.org/10.1182/blood-2011-01-331702
M3 - Article
C2 - 21948297
SN - 0006-4971
VL - 118
SP - 5178
EP - 5188
JO - Blood
JF - Blood
IS - 19
ER -