氢氧化铝佐剂对铜绿假单胞菌11型O-特异性多糖与破伤风类毒素结合物免疫原性和免疫保护性的影响

Effect of Al(OH)_3 adjuvant on immunogenicity and immune protection of a conjugate composed of Pseudomonas aeruginosa(IATS 11) O-specific polysaccharide bounds with tetanus toxoid

目的评价氢氧化铝[Al(OH)3]佐剂对铜绿假单胞菌11型O-特异性多糖与破伤风类毒素结合物免疫原性和免疫保护性的影响。方法用热酚水法提取铜绿假单胞菌11型(IATS 11)菌株的脂多糖(LPS),去除类脂A并纯化O-特异性多糖(O-SP),用1-氰基-4-二甲胺基吡啶四氟硼酸盐(CDAP)活化O-SP,己二酸二肼(ADH)作连接臂,在乙基二甲氨基丙基碳二亚胺盐酸盐(EDAC)作用下,与破伤风类毒素(TT)结合制备出O-SP-TT结合物,并对该结合物进行添加Al(OH)3佐剂和不添加该佐剂的小鼠免疫原性试验和免疫保护性试验。结果加有Al(OH)3佐剂的结合物在小鼠免疫原性试验中,产生了高效价的IgG抗体,与不添加该佐剂试验组相比,差异具有统计学意义(P<0.05);免疫保护性试验表明,添加Al(OH)3佐剂结合物免疫小鼠对5～10 LD50活菌的腹腔攻击具有良好的保护作用。结论 Al(OH)3佐剂对本结合物有优良的免疫增强作用,添加该佐剂的结合物可望有效防止IATS 11型铜绿假单胞菌感染。

Objective To investigate effect of Al（OH）3 adjuvant on immunogenicity and immune protection of a conjugate composed of Pseudomonas aeruginosa（IATS 11）O-specific polysaccharide bounds with tetanus toxoid.Method Lipopolysaccharide（LPS） from Pseudomonas aeruginosa bacteria（IATS 11） was isolated via hot phenol extraction and then hydrolyzed to obtain O-specific polysaccharide（O-SP）.O-SP was activated with CDAP,using adipic acid dihydrazide as a linker.Activated O-SP was conjugated to tetanus toxoid via EDAC mediated condensation reaction.Immunogenicity of the conjugate with Al（OH）3 adjuvant or without the adjuvant and its immune protection were evaluated in mice.The challenge test was conducted in mice immunized with the conjugate.Results Significantly high IgG anti-IATS 11 O-SP levels were induced in the mice immunized with the conjugates with Al（OH）3 adjuvant comparing with that of immunized with the conjugates without the adjuvant（P0.05）.The potency study showed that more than 80% of the mice immunized with the conjugate with the adjuvant survived when challenged with bacteria of 5—10 LD50.Conclusion Al（OH）3 adjuvant showed that great immunopotentiation and the conjugate with the adjuvant is expected to effectively against IATS 11 Pseudomonas aeruginosa.