[Biological response of B-cell lymphoma cells in vitro to 131I-rituximab].
OBJECTIVE
To study the biological response of B-cell lymphoma cells positive for CD20 expression to (131)I-labeled rituximab.


METHODS
Anti-CD20 monoclonal antibody rituximab was labeled with (131)I by means of IODO-GEN method, and its effects on apoptosis of Raji cells were determined by Annexin-V/PI double-labeled cytometry. Its effects on the cell cycles was evaluated by cytometry with PI staining.


RESULTS
The cell apoptosis rate measured by Annexin v-FITC/PI was 51.99% in (131)I-rituximab group, significantly higher than that in (131)I group, rituximab group and control group (42.71%, 29.42% and 26.17%, respectively, P<;0.05). The apoptosis rate by flow cytometry with PI staining was 4.32% in (131)I-rituximab group, also significantly higher than that in the other 3 groups (1.47%, 1.39% and 0.37%, respectively, P<0.05). Cell cycle alteration of Raji cells occurred in (131)I-rituximab group, and the majority of cells were arrested at G(1)/G(2) stage.


CONCLUSIONS
(131)I-rituximab can regulate the cell cycle of Raji cells and induce their apoptosis to inhibit their proliferation.
Wei
Li
L
Center of Oncology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Luo
Rong-cheng
RC
Zhang
Jun-yi
JY
Yan
Xiao
X
Fang
Yong-xin
YX
Fei
Li-hua
LH
D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology*; D058846:Antibodies, Monoclonal, Murine-Derived; D018951:Antigens, CD20 / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005434:Flow Cytometry; D006801:Humans; D007457:Iodine Radioisotopes; D016393:Lymphoma, B-Cell / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D016499:Radioimmunotherapy; D000069283:Rituximab
D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D018951:Antigens, CD20; D007457:Iodine Radioisotopes; D000069283:Rituximab; C507388:131I-rituximab