基因疫苗诱导小鼠抗HBV皮下移植瘤免疫研究

Study on immunization of anti subcutaneous transplanting tumor induced by gene vaccine

目的 观察 ＨＢＶ ＤＮＡ 疫苗（ｐＣＲ３－１Ｓ） 诱导Ｂａｌｂ／ ｃ 小鼠（ Ｈ２ｄ） 的特异性细胞免疫应答及其对稳定表达ＨＢｓＡｇ 的小鼠肥大细胞瘤Ｐ８１５ 细胞（Ｐ８１５ＨＢＶＳ） （ Ｈ２ｄ） 成瘤性的影响．方法 肌肉注射ＤＮＡ 疫苗，背部皮下接种Ｐ８１５ＨＢＶＳ 细胞，观察成瘤情况，４ ｈ ５１Ｃｒ 释放法检测小鼠脾细胞ＣＴＬ 活性．结果 接种 ＤＮＡ 疫苗后小鼠成瘤率为１２－５ ％ ， 对照组为１００ ％ ． 小鼠平均存活期大于３８－２ ｄ ，对照组为２８－４ ｄ ，４０ ｄ 后小鼠存活率为８７－５ ％ ，对照组为０ ％ ． ＣＴＬ 细胞杀伤活性明显增加，ｐＣＲ３－１Ｓ 组５１ ％ ，对照组为２１ ％ （ Ｐ＜ ０－００１） ．结论 ＤＮＡ 疫苗可以诱导细胞免疫应答，对体内ＨＢＶ 感染具有预防及治疗作用．

AIM To observe the specific cellular immune responses and the protection against P815 mastocytoma cells stable expressing HBV surface antigen (P815 HBV S) in Balb/*!c (H 2 d) mice after DNA immunization of HBV surface antigen (pCR3 1 S). METHODS The immunization was performed by intramuscular injection in this experiment. Three weeks later, we directly inoculated P815 HBV S into mice by subcutaneous injection. The tumor growth was measured every five days and HBsAg specific cytotoxic T lymphocytes (CTLs) activity was measured by 51 Chromiun release assay. RESULTS HBV S DNA vaccine can evidently inhibit the tumor growth, prolong the survival period (>38 2*!d) and improve the survival rate (87 5%) in mice. Meanwhile, HBsAg specific CTLs activity were obviously increased after DNA immunization (51% vs 21%, P <0 001 ). CONCLUSION The results showed that the DNA vaccine of pCR3 1 S had strong antigenecity in cellular immunity and had marked killing effect on HBV infected cells in vivo . DNA vaccine against HBV may be useful for both prophylactic and therapeutic purposes.