[Inhibitory and lethal effects of human-mouse chimeric antibody against CD80 on the growth of B lymphoma cell lines Raji and Daudi].
OBJECTIVE
To study the inhibitory and lethal effects of human-mouse chimeric antibody against CD80 (named ch-4E5) on the growth of B lymphoma cell lines Daudi and Raji.


METHODS
Immunofluorescence and flow cytometry were used to analyze the detection of membrane CD80 in Raji and Daudi by ch-4E5. After the co-culture of ch-4E5 with Raji and Daudi, respectively, at the final concentration of 10 mg/L, the expression of Fas and FasL was observated to be at the 0 h, 4 h, 10 h, 16 h, 24 h and 48 h by direct immunofluorescence and flow cytometry, and the blocking effect on cell growth of ch-4E5 was determined at 72 h by MTT assay. MTT assay was also used to study the ADCC effect with PBMC as effector cells and Raji and Daudi as target cells. The efficiency target ratio was 20:1.


RESULTS
The combination rate between ch-4E5 and Raji and Daudi was 98.6% and 96.4%, respectively. After the co-culture of ch-4E5 with Raji and Daudi cells for 4 hs, the expression of FasL in Raji began to up-regulate. It reached the peak at 16 h and its positive rate was 16.8%. Compared with human IgG1 control group, it was increased obviously (P<0.01). The expression of Fas increased at 10 h, and then reached the top at 24 h. The combination rate was 15.6%. There was significant deviation compared with human IgG1 control group (P<0.01). Moreover, the expression of FasL and Fas on Daudi was also altered. The trend was similar to these on Raji, and the highest expression was 15.9% and 13.7%, respectively. The inhibitory rate was 34.60% and 32.64% respectively when ch-4E5 with Raji and Daudi had been co-cultured for 72 h (P<0.01). Furthermore, ch-4E5 could mediate the ADCC effect and the maximum killing rate was 55.61% and 54.42%, respectively(P<0.01).


CONCLUSIONS
The human-mouse chimeric antibody against CD80 can inhibit the proliferation of B lymphoma cell lines Daudi and Raji cells through Fab and Fc sections in vitro.
Wang
Yan-ru
YR
Department of Immunology, School of Medicine, Soochow University, Suzhou 215123, China. yanru0925@163.com
Ma
Hong-bing
HB
Chen
Yong-jing
YJ
Zhu
Hua-ting
HT
Liu
Yu-hua
YH
Du
Yang-yang
YY
Sun
Jie
J
Chen
Ming-xin
MX
Qiu
Yu-hua
YH
D000818:Animals; D000906:Antibodies / Q000494:pharmacology*; D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects; D017209:Apoptosis / Q000187:drug effects; D018122:B7-1 Antigen / Q000276:immunology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D016393:Lymphoma, B-Cell / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D011993:Recombinant Fusion Proteins / Q000494:pharmacology*
D000906:Antibodies; D018122:B7-1 Antigen; D011993:Recombinant Fusion Proteins