Recombinant eukaryotic expression plasmid of bcr-abl gene fragment induces specific immune response in mice.
- Author:
Yang-wen JIANG
1
;
Li QIAN
;
Wei-juan GONG
;
Wei LIU
;
Gui-hua JIANG
;
Ming-chun JI
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Female; Fusion Proteins, bcr-abl; genetics; Gene Expression; Genetic Vectors; Immunotherapy; Mice; Mice, Inbred BALB C; Plasmids; genetics; Random Allocation; Transfection
- From: Chinese Journal of Hematology 2006;27(2):111-115
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo study the specific immune response induced by a recombinant eukaryotic expression plasmid encoding bcr-abl fusion gene fragment so as to explore new immunotherapy in mouse.
METHODSA recombinant eukaryotic vector pVbcr-abl expression cDNA fragment of bcr-abl fusion gene was constructed and used to immunize BALB/c mice. Serum level of bcr-abl specific antibody was detected by enzyme-linked immunosorbent assay (ELISA). Twenty days later the immunized mice were subcutaneously inoculated SP2/0/bcr-abl cells. The survival time, tumor growth time and lymphocytic infiltration were observed. T cells infiltration into tumor tissue was analyzed by immunohistochemistry. Changes of T cell subset in the spleen of mice was analyzed by fluorescent-activated cell sorting (FACS) and the cytotoxicity T lymphocyte (CTL) activity in spleen by lactate dehydrogenase (LDH)-release assay.
RESULTSThe eukaryotic expression vector pVbcr-abl was constructed successfully, and highly expressed the cDNA fragment of bcr-abl fusion gene. The BALB/c mice immunized with the vector could generate the specific antibody and CTL, resulting in a specific immunoprotection. There were dramatic differences in the tumor-forming time, tumor ulcer appearing time and tumor-growing speed between the immunized and the control groups. The mice had longer survival time in the immunized group than in the control group. There were a large amount of CD3(+) T cells infiltration in tumor tissue of the immunized mice. The spleen cells from the immunized mice had higher CTL activity with a alteration of T cell subset, the CD4(+)/CD8(+) ratio being 1.54 +/- 0.29, higher than that of control group (1.18 +/- 0.30).
CONCLUSIONThe recombinant eukaryotic expression plasmid pVbcr-abl can induce in vivo not only the generation of specific antibody, but also high level of specific CTL activity, resulting in killing the SP2/0/bcr-abl tumor cells directly and inhibiting the tumor growth.