1株粗糙型布鲁氏菌诱导株RB71的生物学特性研究

目的 通过研究1株粗糙型布鲁氏菌诱导株RB71的毒力及免疫效果，进一步验证其生物学特性，探讨其作为疫苗株的潜力。方法 通过药敏片扩散法检测诱导株RB71对β-内酰胺类及非β-内酰胺类抗生素的耐受程度；通过对小鼠脾脏载菌量测定，评价诱导株RB71对感染小鼠的免疫保护率并确定其最小免疫剂量；利用小鼠感染模型进行毒力试验，比较诱导株RB71与亲本株的毒力差异。结果 诱导后的布鲁氏菌RB71株与亲本株相比，对β-内酰胺类抗生素和非β-内酰胺类抗生素的敏感性未发生改变；诱导株RB71对感染小鼠具有一定的保护效果，最小免疫剂量为10⁹ CFU/只；诱导株RB71与亲本株相比毒力更小，安全性更高。结论 本研究验证了布鲁氏菌诱导株RB71对抗生素的敏感性，其具有良好的免疫原性且具有较低的毒力，具备成为疫苗株的潜力。

Biological characteristics of roughness induced Brucella strain RB71

The purpose of this work was to study the virulence and immune effects of the RB71 strain of Brucella with gene-deletion, to examine its potential as a vaccine strain. The tolerance of RB71 to β-lactam and non-β-lactam antibiotics was tested through the drug sensitive tablet diffusion method, and the minimum immunization dose was evaluated by measurement of mouse spleen bacterial load and spleen index. Virulence testing of the infection model was used to explore the strain’s biological characteristics. The RB71 induced strain did not show altered susceptibility to β-lactam antibiotics and non-β-lactam antibiotics; the mouse infection model test showed that the minimum immune dose of RB71 was 10⁹ CFU, and the gene-deleted RB71 strain was similar to the induced strain. The specific virulence was low. In summary, the RB71 induced strain was sensitive to antibiotics, showed good immune effects, and had low virulence; therefore, it has the potential to serve as a vaccine strain.