论文部分内容阅读
目的研究尿路致病性大肠埃希菌Ⅰ型菌毛fimH基因核酸疫苗产生的免疫反应及其对小鼠的免疫保护作用,并比较不同免疫途径产生的免疫效果。方法选取BALB/c小鼠40只,随机分为4组(PBS组、空质粒组、pcD-NA3.0-fimH肌肉注射组、pcDNA3.0-fimH滴鼻组),用构建的fimH基因真核表达载体pcDNA3.0重组质粒分别通过肌肉注射和滴鼻(粘膜)免疫BALB/c小鼠,同时分别以载体质粒(pcDNA3.0)和PBS液为空质粒对照和空白对照,经股四头肌注射免疫小鼠,于第3周和第5周加强免疫。每次免疫前及末次免疫后2周采血检测特异IgG抗体。末次免疫后第10 d,以UPEC分离株菌液进行尿道上行攻击,攻击后第5 d进行尿液细菌培养和计数。结果免疫后,肌注组与滴鼻组小鼠血清特异性IgG抗体水平与对照组及空质粒组比较显著升高(P<0.05);UPEC分离株菌液攻击小鼠后,pcDNA3.0-fimH肌注组与滴鼻组小鼠尿液菌落数较对照组及空质粒组显著减少(P<0.05)。结论 pcDNA3.0-fimH基因疫苗可诱导BALB/c小鼠产生特异性体液免疫,对小鼠尿道上行感染具有一定的免疫保护作用,且不同的免疫途径免疫效果亦有不同。
Objective To study the immune response induced by fimH DNA vaccine of pathogenic Escherichia coli type Ⅰ pilus and its immunoprotective effect on mice and to compare the immune effects of different routes of immunization. Methods Forty BALB / c mice were randomly divided into 4 groups (PBS group, empty plasmid group, pcD-NA3.0-fimH intramuscular injection group and pcDNA3.0-fimH intranasal group) The recombinant plasmid pcDNA3.0 was immunized BALB / c mice by intramuscular injection and intranasal (mucosal) respectively. At the same time, plasmid pcDNA3.0 and PBS were used as blank plasmid control and blank control, Mice were immunized intramuscularly and boosted at Weeks 3 and 5. Specific IgG antibodies were collected before each immunization and two weeks after the last immunization. On the 10th day after the last immunization, UPEC isolates were challenged with the urethra upward, and the bacteria were cultured and counted on the 5th day after the challenge. Results After immunization, the level of serum specific IgG antibody in intramuscular injection group and intranasal injection group was significantly higher than that in control group and empty plasmid group (P <0.05). After UPEC isolates were challenged with the bacterial solution, pcDNA3.0- The number of urinary colonies in fimH intramuscular group and intranasal group was significantly lower than that in control group and empty plasmid group (P <0.05). Conclusion The pcDNA3.0-fimH gene vaccine can induce specific humoral immunity in BALB / c mice and has protective effect on the upriver of the urethra in mice, and the immune effects of different immunization routes are also different.