[Antitumor therapeutic effect induced by intestine-carcinoma cells vaccine expressing membrane-bound heat shock protein 70].
OBJECTIVE
To develop a new vaccine expressing membrane-bound heat shock protein 70 (mbHSP70) and further study its antitumor therapeutic effect.


METHODS
The pre- established vector expressing mbHSP70 was transfected into CT26 cells of colorectal cancer. After the CT26 cells were incubated with 900 microg/ml G418, the sub-clones resistant to G418 were harvested and the HSP70 positive clones were selected by limiting dilution. The clones were amplified and inactivated, thereby the vaccine expressing mbHSP70 was prepared. Lymphocyte proliferation stimulated by the vaccines, NK and CTL activity was observed. The antitumor efficacy of vaccine was observed in BALB/c mice model with colorectal cancer.


RESULTS
The laser confocal microscopy and flow cytometry showed that there existed much HSP70 on the vaccine membrane surface. The HSP70 gene-modified vaccine displayed augmented lymphocyte proliferation and higher NK and CTL activity in vitro,and marked tumor suppression and prolonged survival time of the vaccinated micein vivo, when compared with its counterpart. Furthermore, mbHSP70-expression vaccine elicited lymphocyte proliferation most intensively, generated the highest NK and CTL activity as well as the strongest antitumor effect, and prolonged survival time of the vaccinated mice.


CONCLUSIONS
A new vaccine expressing mbHSP70 has more potent antitumor immunity and better therapeutic efficacy than HSP70 gene-modified vaccine did.
Huang
Chang-xin
CX
Department of Surgery, Hangzhou Third People's Hospital, Hangzhou 310009, China. yuhai@zju.edu.cn
Yu
Hai
H
Yang
Guan-gen
GG
Wang
Qing-qing
QQ
Shen
Fen-ping
FP
Li
Da
D
Cao
Xue-tao
XT
D000818:Animals; D019496:Cancer Vaccines / Q000627:therapeutic use*; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000276:immunology*; D007167:Immunotherapy; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000628:therapy*; D014162:Transfection
D019496:Cancer Vaccines; D018840:HSP70 Heat-Shock Proteins