乙型肝炎病毒核心区DNA疫苗接种后H—2^d小鼠的特异性免疫应答

Specific immune responses in H-2~d mice after DNA immunization of HBV core gene

目的观察乙型肝炎病毒（ＨＢＶ）核心区ＤＮＡ疫苗接种后ＢＡＬＢ／ｃ（－２ｄ）小鼠的特异性免疫应答。方法构建ＨＢＶ核心区ＤＮＡ疫苗（ＰＪＷ４３０３／ＨＢｃ）；用基因枪法和肌肉注射祛将该ＤＮＡ疫苗接种ＢＡＬＢ／ｃ小鼠；ＥＬＩＳＡ法检测小鼠血清抗－ＨＢＣ（ＩｇＧ）及ＩｇＧ亚类（ＩｇＧ１，ＩｇＧ２ａ）；５１铬释放法检测小鼠脾细胞ＨＢｃＡｇ特异性ＣＴＬ活性。结果该ＤＮＡ疫苗在体外转染细胞中可良好表达ＨＢｃＡｇ。血清抗－ＨＢｃ终点滴度在ＤＮＡ疫苗基因枪组和肌肉注射接种组小鼠分别为１：３２８０５０和１：１０９３５０．两组小鼠的抗－ＨＢｃＩｇＧ亚类均以ＩｇＧ２ａ略占优势。两组小鼠的ＨＢＣＡｔｈｅ异性ＣＴＬ杀伤活性分别达到５１．１％和５５．２％。结论ＨＢＶ核心区ＤＮＡ疫苗在小鼠实验中具有良好的细胞免疫和体液免疫原性。

Objective To oborve the specific immune responses in H-2d mice after DNA immuni-zation of HBV core gene.Methods The DNA vaccine (pJW4303/HBc) was constructed by inserting HBVcore gene fragment into the reading frame of plasmid pJW4303. Both methods of bine gun and intramuscular immunization were used in this experiment. Anti-HBc (IgG) and its isotypes (IgG1, IgG2a) in micesera were detected by ELISA. HBcAg speific cytotoxic T lymphocyte (CTL) activity was measured bySICr release assay. Results The expression of HBcAg was confirmed by ELISA and Western-blot in 293Tcells transfected with pJW4303/HBc. The end-point titers of serum anti-HBc in immunized mice were 1:328050 (gene gun method) and 1:109 350 (intramuscular method). In both groups of gene gun and intra- muscular immunization IgG2a level was slightly higher than IgG1. HBcAg speific CTL activities were 51.1% in gene gun group and 55.2% in intramuscular group. Conclusion in this experiment the DNA vaccineof pJW4303/HBc shows strong antigunecity in both cullular and humoral immunity.