RESUMO
Murine studies have shown that immunological targeting of fibroblast activation protein (FAP) can elicit protective immunity in the absence of significant pathology. Fibroblast activation protein is a product overexpressed by tumor-associated fibroblasts (TAF) and is the predominant component of the stoma in most types of cancer. Tumor-associated fibroblasts differ from normal adult tissue fibroblasts, and instead resemble transient fetal and wound healing-associated fibroblasts. Tumor-associated fibroblasts are critical regulators of tumorigenesis, but differ from tumor cells by being more genetically stable. Therefore, in comparison to tumor cells, TAF may represent more viable therapeutic targets for cancer immunotherapy. To specifically target TAF, we constructed a DNA vaccine directed against FAP. This vaccine significantly suppressed primary tumor and pulmonary metastases primarily through CD8(+) T-cell-mediated killing in tumor-bearing mice. Most importantly, tumor-bearing mice vaccinated against FAP exhibited a 1.5-fold increase in lifespan and no significant pathology. These results suggest that FAP, a product preferentially expressed by TAF, could function as an effective tumor rejection antigen.
Assuntos
Neoplasias do Colo/terapia , Gelatinases/imunologia , Imunoterapia/métodos , Proteínas de Membrana/imunologia , Serina Endopeptidases/imunologia , Vacinas de DNA/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Endopeptidases , Feminino , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Gelatinases/genética , Gelatinases/metabolismo , Humanos , Imunização/métodos , Imuno-Histoquímica , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Análise de Sobrevida , Carga Tumoral/imunologia , Vacinas de DNA/genéticaRESUMO
OBJECTIVE: To construct a recombinant adenovirus Ad-HBx-mlL-12 carrying HBx and mIL-12. METHODS: HBx and mIL-12 were cloned into the shuttle plasmid pAdenoVator-CMV5 and confirmed by means of enzymatic manipulation. After linearization by EcoR I digestion, the recombinant shuttle plasmid pAdV-HBx-mIL-12 was transformed into competent BJ5183 germs with the adenoviral backbone plasmid pAdenoVator deltaE1/E3 and then homologically recombined to obtain the recombinant adenovirus plasmid. After confirmation, the recombinant adenovirus plasmid pAd-HBx-mIL-12 was linearized with Pac I digestion and transfected into 293 cells via liposome, and then adenovirus package and amplification were performed. RESULTS: It was confirmed that the recombinant adenovirus Ad-HBx-mIL-12 had been successfully constructed and both HBx and mIL-12 were expressed in 293 cells. CONCLUSION: The recombinant adenovirus carrying HBx and mIL-12 has been successfully constructed, which lays a foundation for the further study of antitumor mechanism and gene therapy.