缓释伤寒荚膜多糖微球疫苗免疫动物的实验研究

Experimental Study of Controlled Release Microencapsulated Samonella Typhi Capsular Polysaccharide Vaccines Immunized Mice

用 PEL A为材料包裹伤寒沙门菌荚膜多糖 ,制成缓释微球疫苗 ,分别以口服及皮下注射的方式免疫BAL B/ C小鼠 ,分别在第 2 ,4 ,8周取血 ,收集唾液 ,用 RIA方法检测血清中 Ig G抗体及唾液中 s Ig A抗体效价。第 8周腹腔注射伤寒沙门菌活菌攻击各组免疫动物 ,计算免疫动物保护率。单剂微球疫苗皮下注射比常规液体疫苗更有效地诱导全身免疫应答 (P<0 .0 5 ) ,而口服微球疫苗组和微球疫苗皮下注射组均可诱导较强粘膜免疫 (P<0 .0 5 )。动物保护力实验表明 ,口服微球疫苗组免疫保护率 4 0 % ,微球疫苗皮下注射组免疫保护率为 10 0 % ,常规液体疫苗免疫保护率为 6 0 %。缓释伤寒荚膜多糖微球疫苗具有在体内释放速度慢 。

Samonella Typhi capsular polysaccharide vaccines were encapsulated in the Micro particles made from polyethylene glycol poly DL lactide (PELA). BALB/c mices were divided into three groups with 20 mice in each. Mices were immunized respectively with controlled release microencapsulated Samonella Typhi capsular polysaccharide vaccines and Samonella Typhi capsular polysaccharide vaccines by oral and subcutaneous administration. The mice blood and salvia were collected at the 2nd, 4th and 8th weeks respectively for the titrating of IgG and sIgA antibodies by RIA. At the 8th week, live typhoid bacteria were injected into the immunized mice for the calculation of the rate of immunization protection. The IgG titers of the controlled release microencapsulated Samonella Typhi capsular polysaccharide vaccines group were higher than those of the other groups( P <0.05). The IgA titers of the tow groups of controlled release microencapsulated Samonella Typhi capsular polysaccharide vaccines (oral and subcutaneous) were higher than those of the group of Samonella Typhi capsular polysaccharide vaccines( P <0.05). The immunization protection rates of the three groups were 40%,100% and 60% respectively. The controlled release microencapsulated Samonella Typhi capsular polysaccharide vaccines possess the advantages of releasing slowly in vivo and persisting long time immunogenicity.