[Adenovirus mediated targeted genetherapy of Staphylococcal enterotoxin A and CD80 for hepatoma and its primary immune mechanisms].
OBJECTIVE
To observe the effects of hepatoma-targeting recombinant adenovirus vectors of staphylococcal enterotoxin A (SEA) and/or CD80 gene on hepatoma and to study its immunological mechanisms.


METHODS
Using AdEasy adenovirus system, we constructed recombinant adenovirus vectors of SEA and/or CD80 gene driven by alpha-fetoprotein (AFP) enhancer I and promoter. After intratumoral therapy for the mice bearing subcutaneous xenograft hepatoma with the recombinant adenoviruses, SEA and/or CD80 mRNA and protein were detected by RT-PCR and Western blot. IFN-gamma-producing cell frequency and specific cytotoxicity of T lymphocytes to Hepa1-6 cells were detected by ELISpot and LDH-released assay in the splenocytes. Effects of recombinant adenoviruses on hepatoma were assessed by changes of tumor volumes and survival time in the treated mice.


RESULTS
The recombinant adenoviruses constructed by us made SEA and/or CD80 mRNA and protein targetedly express in hepatoma tissues. When compared with the empty vector and PBS groups, the IFN-gamma-producing cell frequency and specific cytotoxicity of T lymphocytes increased, the tumor volumes of mice decreased and the survival time increased in the double-gene and single-gene groups. Double genes elicited better antitumor effects and stronger immune responses. There were no significant differences in the effects between CD80 group and SEA group or between empty vector group and PBS group.


CONCLUSIONS
The hepatoma-targeting recombinant adenovirus vectors constructed in this study can elicit effective antitumor effects on hepatoma and the effects of double genes are better than that of single gene.
Si
Shao-yan
SY
Experimental Center for Medicine, 306th Hospital of PLA, Beijing 100101, China. sishy306@yahoo.com.cn
Hu
Pei-zhen
PZ
Huang
Yang
Y
Li
Xia
X
Ge
Wei
W
Zhang
Xiu-min
XM
Sui
Yan-fang
YF
Zhang
Jian-zhong
JZ
Zhang
Ming
M
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D018122:B7-1 Antigen / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D004742:Enhancer Elements, Genetic / Q000235:genetics; D004768:Enterotoxins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics; D008113:Liver Neoplasms / Q000628:therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D011401:Promoter Regions, Genetic / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000509:alpha-Fetoproteins / Q000235:genetics
D018122:B7-1 Antigen; D004768:Enterotoxins; D000509:alpha-Fetoproteins; C026066:enterotoxin A, Staphylococcal