CpG寡脱氧核苷酸增强免疫抑制小鼠对乙肝疫苗的免疫应答

目的 :探讨CpG寡脱氧核苷酸 (ODN)增强免疫抑制小鼠对乙肝疫苗的免疫应答效果。方法 :选用环磷酰胺 (CTX)所致免疫抑制模型小鼠 ,以乙肝疫苗和 2 0 μgCpGODN联合或单独左胫前肌肌注免疫C5 7BL/6小鼠。 2wk后以同样剂量加强免疫 1次 ,再过 3wk后摘除眼球取血 ,用ELISA法检测抗 HBsIgG抗体和IL 12的水平。同时 ,无菌取脾脏做HE染色 ,观察脾脏淋巴细胞的数量和细胞核的变化。结果 :CpGODN与疫苗联合注射组产生的绝对抗体量比单独注射疫苗组提高 1倍 ;注射组产生IL 12的水平较单独注射疫苗组也有明显升高。光镜下各组脾脏淋巴细胞的变化如下 :正常对照组脾脏可见大量的淋巴细胞 ;与正常对照组相比较 ,CTX组的淋巴细胞明显稀少 ;而CTX加CpG组的淋巴细胞数明显增多 ,细胞核也明显增大。结论 :CpGODN能增强免疫抑制小鼠对乙肝疫苗的免疫应答

Enhancement of immune responses to hepatitis B vaccine in immunodepressed mice by CpG oligodeoxynucleotide

AIM: To investigate enhancement of immune responses to hepatitis B vaccine in immunosuppressed mice by CpG oligodeoxynucleotide (ODN). METHODS: Immunodepressed C57BL/6 mice caused by cytoxan were given an injection of either hepatitis B vaccine alone or hepatitis B vaccine and CpG ODN into the left tibialis anterior muscle, then the mice were given another shot after 2 weeks using the same formulation. Blood was collected at 5 weeks after immunization and anti-hepatitis B surface antigen IgG and IL-12 levels were measured by ELISA. Spleens of immunized mice were observed under microscope. RESULTS: There was a two-fold increase in anti-hepatitis B surface antigen IgG level when hepatitis B vaccine was mixed with CpG ODN to immunize immunodepressed mice. There was a significant increase in IL-12 level when hepatitis B vaccine was mixed with CpG ODN. Under optical microscope, there were fewer lymphocytes in immunodepressed mice than in normal control group. The proliferation level of spleen lymphocytes in CpG ODN group was elevated compared with that of normal control group and nuclei of lymphocytes became larger. CONCLUSION: CpG ODN can enhance the immune (responses) to hepatitis B vaccine in immunodepressed mice.