摘要
目的观察SARS S DNA疫苗经不同的免疫途径及免疫次数,所诱导的免疫效果之间的差异。方法 C57BL/6小鼠经肌肉和皮下途径初次或加强免疫SARS S DNA疫苗,取其脾和肺淋巴细胞经S抗原多肽刺激以后,应用ELISA、ELISPOT和FACS等检测诱导细胞产生细胞因子情况。结果肌肉初次免疫后产生IFN-γ的量较低(均值脾:2.7 pg/ml;肺:68.9 pg/ml),加强免疫2次或3次后IFN-γ水平明显提高(脾:809.2～1398.7 pg/ml;肺:202.3～534.6 pg/ml),与初次免疫比较差异有统计学意义(脾P<0.001,肺P<0.05)。皮下二次免疫后IFN-γ产生量为54.3～106.1 pg/ml,但三次免疫后IFN-γ量显著提高均值达到729.1 pg/ml与对照组比较P<0.05。二次免疫后抗原特异性阳性细胞的频率肌肉免疫(188个/2×105细胞)高于皮下免疫(57个/2×105细胞),两者差异有统计学意义(P<0.05),而免疫3次后2种免疫途径可诱导数量相当的特异性阳性细胞(169～198个/2×105细胞,P>0.05)。S抗原特异性CD4+T细胞亚群以分泌IL-2为主,而抗原特异性CD8+T细胞分泌IFN-γ为主。结论经肌肉和皮下2种途径注射SARS S DNA疫苗免疫后,均可诱导小鼠产生特异性细胞免疫应答;加强免疫后诱导免疫应答明显强于初次免疫;肌肉免疫两次或皮下免疫三次后可达最佳免疫效果。
We aimed to evaluate the immune responses induced by SARS S DNA vaccine in different protocols.C57BL/6 mice were primed and boosted with SARS S DNA vaccine in intramuscular（i.m） or subcutaneous（s.c） ways.By day 7 after vaccination,single cells from spleen and lung were prepared and stimulated with pooled SARS S peptides.The production of cytokines was assayed by ELISA,ELISPOT and FACS.Significant higher level of IFN-γ（spleen： 809.2-1398.7 pg/ml;lung： 202.3-534.6 pg/ml） in culture supernatants were observed in i.m boosted mice than in those of primed ones（spleen： 2.7 pg/ml;lung： 68.9 pg/ml）.The level of IFN-γ increased to 729.1 pg/ml in mouse s.c immunized for three times,which was higher than those in control groups（P〈0.05）.After the second vaccination,i.m vaccinated mouse produced more frequencies of antigen specific cells（188 per 2×105 splenocytes） than s.c vaccinated ones（57 per 2×105 splenocytes,P〈0.05）,however the frequency of s.c vaccinated ones was increased after the third vaccination（169-198 per 2×105 splenocytes,P〉0.05）.We also found that S peptide specific CD4＋ T cells mainly produced IL-2,though the most of IFN-γ was expressed by antigen specific CD8＋ T cells.The above results indicated that specific cellular immune responses could be induced by both i.m and s.c vaccinations with SARS S DNA.And boost immunization enhances the cellular immune responses in vivo.The best immune responses are appeared after the second i.m vaccination and the third s.c vaccination.
出处
《免疫学杂志》
CAS
CSCD
北大核心
2011年第1期13-18,共6页
Immunological Journal
基金
国家科技部863项目(2007AA02Z415)
关键词
严重急性呼吸综合征
疫苗
免疫应答
Severe acute respiratory syndrome
Vaccine
Immune response
