乙型肝炎核酸疫苗NV-HB/s肌注小鼠后HBsAg的表达和抗-HBs的诱生及局部病理观察

HBsAg expression, anti HBs induction and pathological observation in the mice inoculated with DNA vaccine against Hepatitis B

目的研究乙型肝炎核酸疫苗肌注小鼠后在体内的表达及小鼠体液免疫应答的规律，同时观察接种局部组织的病理变化。方法以乙型肝炎核酸疫苗ＮＶ－ＨＢ／ｓ肌注小鼠，然后定期分批处死，采集肌注局部组织检测ＨＢｓＡｇ（ＡＢＣ免疫组化法），采集外周血标本检测ＨＢｓＡｇ和抗－ＨＢｓ（ＥＬＩＳＡ法），并常规病理检查。结果接种乙型肝炎核酸疫苗后１周，ＨＢｓＡｇ的表达即可在部分受检小鼠的肌注局部组织内检出；接种后２周，全部受检小鼠的肌注局部组织ＨＢｓＡｇ检测均呈阳性，部分受检小鼠的外周血抗－ＨＢｓ亦阳转，此后检出率进一步增高。接种后１个月，受检小鼠抗－ＨＢｓ即全部阳转并持续到接种后半年以上；同期间内，至少７５％的受检小鼠其肌注部位组织仍保持ＨＢｓＡｇ检出阳性，而其外周血标本内的ＨＢｓＡｇ检测则始终呈阴性。病理检查提示：核酸疫苗接种后，仅在肌注局部出现一过性非特异性炎症反应。结论乙型肝炎核酸疫苗ＮＶ－ＨＢ／ｓ肌注接种小鼠后，可通过在注射部位组织中表达ＨＢｓＡｇ，在其体内诱生特异性抗－ＨＢｓ。

Objective To study if special humoral immunological response can be induced by DNA vaccine against Hepatitis B (NV HB/s) and its mechanism.Medthods The Balb/C mice inoculated with NV HB/s by intramuscular injection were detected for HBsAg(the expressed product of NV HB/s)by ABC immunohistochemistry or ELISA, and for anti HBs by ELISA and also performed the routine pathological examination. Results After inoculated with NV HB/s, HBsAg could be detected from mice muscle tissue samples of injected sites one week later and almost kept positive(75% and even more) up to 6 th month, but was undetectable from all the serum samples during this period; anti HBs could be detected from serum samples of some mice two weeks later and of all the mice detected one month later, it still kept positive at 6 th month while the mice were sacrificed. Under microscope, only non specific inflammation was found in the muscle tissues of injected sites and could completely recover within 4 weeks, no matter whether the mice were inoculated with NV HBs, or with traditional HB vaccine derived from blood, or even with PBS as control.Conclusion DNA vaccine against Hepatitis B (NV HB/s) can successfully express HBsAg in the muscle tissue of mice by intramuscular inoculation and subseguently induce anti HBs in viro .