HBcAg DNA疫苗诱导小鼠（H—2^b）特异性细胞和体液免疫应答

Specific cellular and humoral immune responses in H 2 b mice induced by DNA immunization of HBV core gene

目的观察ＨＢｃＡｇＤＮＡ疫苗（ｐＪＷ４３０３／ＨＢｃ）免疫Ｃ５７ＢＬ／６小鼠（Ｈ２ｂ）的特异性细胞和体液免疫应答。方法基因枪和肌肉注射两种方法接种ＤＮＡ疫苗；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疫苗体外可表达ＨＢｃＡｇ；小鼠经基因枪或肌肉注射接种该疫苗后血清抗ＨＢｃ滴度分别达１∶３２８０５０和１∶１０９３５０；肌肉注射组抗ＨＢｃ亚类以ＩｇＧ２ａ为主；两种方法接种小鼠的特异性ＣＴＬ杀伤率分别达５３．１％和５２．８％。结论ＨＢｃＡｇＤＮＡ疫苗在Ｈ２ｂ小鼠实验中表现出良好的细胞免疫和体液免疫原性。

Objective To observe the specific cellular and humoral immune responses in H 2 b mice after DNA immunization of HBV core gene.Methods The DNA vaccine(pJW4303/HBc) was constructed by inserting HBV core gene fragment into the reading frame of plasmid pJW4303.The immunization was performed by gene gun and intramuscular injection in this experiment.Anti HBc(IgG)and its subtypes(IgG1,IgG2a)in mice sera were detected by ELISA.HBcAg specific cytotoxic T lymphocyte (CTL) activity was measured by 51 Chromium release assay.Results The expression of HBcAg was demonstrated by ELISA and Western blot in 293T cells transfected with pJW4303/HBc.The end point titers of serum anti HBc in immunized mice were 1∶328 050 (gene gun method) and 1∶109 350 (intramuscular method).In both groups of gene gun and intramuscular immunization,IgG2a level was sightly higher than that of IgG1.HBcAg specific CTL activities were 53.1% in gene gun group and 52.85%in intramuscular group.ConclusionThe results showed that the DNA vaccine of pJW4303/HBc had strong antigenecity in both cellular and humoral immunity.