基因佐剂CpGDNA对生长抑素DNA疫苗pES/2SS的作用

 【目的】探讨CpGDNA对生长抑素DNA疫苗免疫小鼠免疫效果的影响。【方法】生长抑素质粒pES/2SS分别与CpG-ODN、pE-CpG、细菌DNA、脂质体配合免疫小鼠，疫苗剂量为20μg/只，佐剂等量混合，2周后加强免疫。【结果】雌性小鼠免疫后4、6周，疫苗组平均增重显著高于对照组(P<0.05)。CpGDNA和DNA疫苗联合免疫后SS抗体P/N值、IgG2a/IgG1、脾细胞活性、GH和IGF-I均比单一使用DNA疫苗的高(P<0.05)。免疫后4周，P/N值以pES/2SS + CpGODN组最高，SI值以pES/2SS+ CpG-ODN组最高。CpGDNA佐剂组GH从第2周开始升高，至第6周达高峰，显著高于pES/2SS组（P<0.01），CpG-ODN组GH高水平持续时间最长，至免疫后8周，仍显著高于pES/2SS组（P<0.01）。CpGDNA组IGF-I值显著高于pES/2SS疫苗组（P<0.05）。【结论】生长抑素基因免疫小鼠可以产生SS抗体，而含CpGDNA序列的核酸佐剂及脂质体粗品，可以增强生长抑素基因疫苗的效果。

Effect of Gene Adjuvant CpGDNA on the Somatostatin DNA Vaccine in Mice

Abstract: To investigate the immune effect of CpG DNA on DNA vaccine against somatostatin (SS), experimental mice at the age of 20 days were immunized with somatostatin eukaryotic expression plasmid pES/2SS with different adjuvant, such as the synthetic CpG- ODN, the pE-CpG plasmid, E.coli DNA and the crude liposome in the current study. The antibody against SS level and the spleen lymphocyte proliferation were detected by ELISA and MTT colorimetric assay , the concentration of GH and IGF-Ⅰwere detected by RIA assay. The results showed that the antibody against SS level , spleen lymphocyte proliferation activity and the concentrations of GH and IGF-Ⅰin the groups of CpGDNA combined the DNA vaccine was significantly increased compared with the group immunized with DNA vaccine alone. Our results suggest that the recombinant somatostatin expression plasmid can stimulate animal to produce antibody against SS, CpGDNA as adjuvant can enhance the immune effect of DNA vaccine against SS and influence the concentration of GH and IGF-Ⅰ