摘要
目的建立金黄色葡萄球菌(简称金葡菌)荚膜多糖型CP8菌小鼠全身感染模型,并对模型进行免疫攻毒保护性评价。方法金葡菌荚膜多糖型CP8国际标准株49525经37℃培养24 h,用PBS缓冲液稀释成不同浓度菌液,分组经腹腔注射感染BALB/c小鼠,观察小鼠发病症状,统计生存率及体重变化,确定每只小鼠的致死剂量及亚致死剂量;采集不同感染时间的小鼠血液及心脏、肝脏、脾脏、肺、肾脏,进行细菌定植量检测及主要脏器病理学检查。用CP8多糖-蛋白偶联物(实验组)及氢氧化铝佐剂(对照组)对建立的小鼠模型进行3次免疫攻毒保护性实验,统计小鼠存活率。结果经腹腔感染途径建立的小鼠模型,每只致死剂量为3.0×10^9 CFU,亚致死剂量为1.5×10^9 CFU。感染发病小鼠表现为翘毛弓背、耸肩及行动迟缓,生存率及体重随感染剂量增加明显下降,血液及心脏、肝脏、脾脏、肺、肾脏均有细菌定植,心脏、肾脏、肝脏主要脏器中可见明显细胞坏死和炎性细胞浸润。与对照组比较,实验组小鼠3次攻毒存活率差异均有统计学意义(P均<0.01),对小鼠的保护率分别为55.6%、50.0%和57.1%。结论成功建立金葡菌荚膜多糖型CP8菌小鼠全身感染模型,并可用于疫苗保护性评价,为进一步研究多抗原组分疫苗的有效性和安全性奠定了实验基础。
Objective To establish a mouse model of systemic infection induced by Staphylococcus aureus capsular polysaccharide type CP8 strain and evaluate its immunoprotection against challenge.Methods International standard strain 49525 of S.aureus was cultured at 37℃for 24 h and diluted to various concentrations with PBS,with which BALB/c mice were infected by intraperitoneal injection and observed for clinical symptoms.The survival rate and bodyweight change of mice were calculated,based on which the lethal and sub-lethal dosages were determined.The blood,heart,liver,spleen,lung and kidney of mice at various time points after infection were collected for determination of bacterial colonization and pathological examination.The mice were divided into CP8 polysaccharide-protein conjugate(test)and aluminum hydroxide(control)groups and subjected to 3 times of protection test against challenge,of which the survival rates were calculated.Results The lethal dosage was 3.0×10^9 CFU,while the sub-lethal dosage was 1.5×10^9 CFU.Typical manifestations of systemic infection were observed in the mice,including hunched posture,ruffled fur and impaired mobility.The survival rate and bodyweight decreased significantly with the increasing infectious dosage.Bacterial colonization was observed in blood,heart,liver,spleen,lung and kidney of mice,while cell death and infiltration of inflammatory cells in heart,kidney and liver.The survival rates of mice in test group in 3 times of protection test showed significant difference with that in control group (each P < 0. 01),while the protection rates were 55. 6%,50. 0% and 57. 1% respectively. Conclusion A systemic infection model of S. aureus capsular polysaccharide type CP8strain was successfully established,which might be used for the evaluation of protection of vaccine. It laid a foundation offurther study on the effectiveness and safety of multiple-antigen component vaccine.
作者
袁玉兰
郭京蓉
林海涛
周继唯
张云涛
YUAN Yu-lan;GUO Jing-rong;LIN Hai-tao;ZHOU Ji-wei;ZHANG Yun-tao(National Vaccine and Serum Institute,Beijing 101111,China)
出处
《中国生物制品学杂志》
CAS
CSCD
2019年第11期1228-1233,共6页
Chinese Journal of Biologicals
关键词
金黄色葡萄球菌
荚膜多糖型CP8菌
全身感染
小鼠模型
保护性评价
Staphylococcus aureus
Capsular polysaccharide type CP8 strain
Systemic infection
Mouse model
Protection evaluation
