目的研究大肠杆菌不耐热肠毒素无毒突变体mLT63和CpG-ODN鼻内免疫对抗原的佐剂效应。方法选用破伤风类毒素(TT)和小牛血清白蛋白(BSA)为抗原,mLT63和CpG-ODN为佐剂,经鼻内免疫BALB/c小鼠。ELISA间接法检测免疫小鼠血清和肺、直肠及阴道组织萃取液的特异性抗TT、BSA的IgA、IgG水平。结果mLT63和CpG-ODN均能协助TT和BSA抗原在血清、肺、阴道、直肠组织中诱导出高滴度的IgG抗体。在血清中IgA抗体滴度均比较低,而TT-IgA在肺和阴道组织中滴度较高,BSA-IgA在肺组织中滴度较高。各佐剂组之间IgG和IgA抗体水平相比,差异均无显著意义。不同剂量的mLT63诱导的BSA-IgA抗体水平差异无显著意义。结论mLT63和CpG-ODN经鼻内免疫对TT和BSA抗原均有良好的佐剂作用。
Objective To study the role of mLT63,an avirulent mutant of heat-liable E. coli enterotoxin, as an adjuvant in intranasal immunization and compare with that of CpG-ODN. Methods Immunize BALB/c mice by intranasal route with tetanus toxoid (TT) and bovine serum albumin(BSA) as antigens and mLT63 and CpG-ODN as adjuvant. Determine the IgA and IgG levels against TT and BSA in sera,lungs and extracts of rectal and vaginal tissues by ELISA. Results Both mLT63 and CpG-ODN promoted the induction of IgG antibody with TT and BSA in sera,lungs and extracts of rectal and vaginal tissues. The IgA levels in sera were low. How- ever ,high TT-IgA titers were induced in lung and vaginal tissues,and high BSA-IgA titer in lung tissue. The IgG and IgA titers induced using mLT63 and CpG-ODN as adjuvant showed no significant difference. The BSA-Ig, A levels induced with mLT63 at various dosages showed no significant difference. Conclusion Both mLT63 and CpG-ODN showed good adjuvanticity in intranasal immunization with TT and BSA.