构建重组肿瘤基因疫苗对肿瘤进展及生存率影响的实验结局

目的 利用 P815肿瘤动物模型观察 IL- 12对肿瘤动物模型抗肿瘤作用的效应. 方法 将小鼠肥大细胞瘤 P815特异抗原基因 P1A克隆到真核表达质粒 pCI- neo中;用 P815细胞对 DBA/2小鼠右腹侧皮下注射,构建 P815小鼠肿瘤模型;以重组基因疫苗单独或与鼠 IL- 12真核表达质粒一起肌肉注射,观察肿瘤的消长、特异细胞毒 T淋巴细胞激活和抗体的生成情况. 结果 重组基因疫苗在体外有很好的表达,注射后细胞毒性 T淋巴细胞(CTL)的杀伤效率为 40%, IL- 12共注射的 CTL杀伤效率达到 60%.免疫后, 30%小鼠的肿瘤出现消退;同 IL- 12共注射则有 50%的小鼠的肿瘤出现消退.两种情况下都不能检测到任何特异抗体的产生. 结论 长期存在的 IL- 12可以持续刺激机体细胞免疫,使肿瘤的生存环境持续恶化,从而达到治疗肿瘤的目的.

Effect of recombinant genetic vaccine against tumors on tumor progression and survival rate of mice

AIM:To study the immunological effect of genetic vaccine co- administered with murine IL- 12 against mouse mastocytoma P815. METHODS:Antigen- specific P1A gene of P815 mastocytoma was transduced into the eukaryotic expression vector pCI- neo to prepare the genetic vaccine.Mouse models of P815 tumor were established by subcutaneous injection of P815 cells,and the growth of the tumor, the stimulation of cytotoxic T cells and production of specific antibodies were observed following injection of the recombinant vaccine into mice muscle alone or together with IL- 12- expression plasmids. RESULTS:The recombinant vaccine could be expressed in vitro, with specific release rate of cytotoxic T cells reaching 40% after injection alone, which mounted up to 60% when IL- 12- expressing plasmid was co- administered.About 30% of the recombinant P1A vaccine- inoculated mice showed signs of tumor regression, and when IL- 12- expressing plasmid was used,the regression could reached 50% .No antibodies, however, could be detected in the sera of any of the immunized mice. CONCLUSION:Tumor- specific immunological response can be elicited by recombinant P1A vaccine through cellular immunity,and IL- 12 can enhance the immune effect of this vaccine.