卡介苗预先免疫对大鼠慢性绿脓杆菌性肺炎的影响

为了探讨卡介苗 (BCG )预先免疫对大鼠慢性绿脓杆菌 (PA )性肺炎模型的影响。采用BCG或灭菌生理盐水皮内注射预先免疫 3周 ,然后由支气管内予以PA攻击 ;2周后评估各组的肺部细菌学、肺组织病理学、肺部细胞因子 (IL 4、IFN γ、TNF α )反应、血清PA特异性抗体IgG水平的变化。结果显示BCG免疫组肺组织内的IFN γ、TNF α水平显著升高 (P <0 0 5 ) ,肺组织匀浆PA菌落计数明显低于生理盐水对照组 (P <0 0 1) ;肺组织病理改变及血清PA特异性抗体IgG水平两组均无显著差异 (P >0 0 5 )。以上结果提示BCG接种能够诱导肺部Th1型免疫反应 ,加快PA性肺炎大鼠肺部的细菌清除 ,因而对PA感染大鼠具有保护作用

Effects of Pre-Immunization with Bacillus Calmette Guerin Vaccine on Chronic Lung Infection P.aeruginosa in Rats

To observe the effect of pre-immunization with BCG on a rat model of chronic Pseudomonas aeruginosa pneumonia,0.1 ml of BCG or 0.9% sterile saline was injected intracutaneously to the rats 22 days before intratracheal challenge with P.aeruginosa alginate beads. Two weeks after intratracheal challenge with P.aeruginosa the BCG group with P.aeruginosa infection showed a significantly improved lung bacterial clearance with higher inductions of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in the lungs compared with the control group. There were no significant differences in the lung pathology,serum IgG response against P.aeruginosa sonicate and lung IL-4 response. These results suggest that BCG immunization can induce stronger local IFN-γ and TNF-α responses in the lungs leading to a faster bacterial clearance from the lungs.