Davidson M K, Davis J K, Lindsey J R, Cassell G H
Department of Comparative Medicine, University of Alabama, Birmingham.
Infect Immun. 1988 Aug;56(8):2163-8. doi: 10.1128/iai.56.8.2163-2168.1988.
Pathogen-free C3H/HeN mice were exposed by aerosol to Mycoplasma pulmonis PG34(ASH), UAB 5782C, M1, UAB T, or UAB CT, and clearance of mycoplasmas from the nasal passages, trachea, and lungs was determined during the first 72 h postinoculation (PI). There were differences among strains of mycoplasmas in physical removal of organisms and in killing by nonspecific factors in the nasal passages and trachea. The avirulent strain, PG34(ASH), was quickly removed from the nasal passages and trachea. Physical removal of the other mycoplasmal strains occurred slowly, with 60 to 89% of the radioactive label remaining in the nasal passages and trachea even after 72 h. There were significant differences in killing among mycoplasmal strains by nonspecific host mechanisms in the nasal passages, trachea, and lungs. Strain UAB T was quickly killed at all levels of the respiratory tract. Strains UAB 5782C and M1 were killed at all three sites by 2 to 4 h PI. The most virulent strain, UAB CT, was killed much more slowly than the other strains. However, there was no statistical difference in the relative numbers of mycoplasmas present in the lungs at 72 h PI among strains UAB CT, UAB 5782C, and M1. These studies showed that the different mycoplasmal strains were cleared from the respiratory tract by different mechanisms and suggest that the differences in virulence among the mycoplasma strains can be explained, in part, by the differences in elimination of the organisms from the respiratory tract by nonspecific host defense mechanisms.
将无特定病原体的C3H/HeN小鼠通过气溶胶暴露于肺支原体PG34(ASH)、UAB 5782C、M1、UAB T或UAB CT，在接种后（PI）的前72小时测定支原体从鼻腔、气管和肺部的清除情况。支原体菌株在鼻腔和气管中生物体的物理清除以及非特异性因素的杀灭方面存在差异。无毒力菌株PG34(ASH)很快从鼻腔和气管中清除。其他支原体菌株的物理清除过程缓慢，即使在72小时后，仍有60%至89%的放射性标记物残留在鼻腔和气管中。支原体菌株在鼻腔、气管和肺部通过非特异性宿主机制的杀灭存在显著差异。UAB T菌株在呼吸道的各个水平都被迅速杀灭。UAB 5782C和M1菌株在接种后2至4小时在所有三个部位被杀灭。毒性最强的菌株UAB CT的杀灭速度比其他菌株慢得多。然而，在接种后72小时，UAB CT、UAB 5782C和M1菌株在肺部存在的支原体相对数量没有统计学差异。这些研究表明，不同的支原体菌株通过不同的机制从呼吸道清除，这表明支原体菌株毒力的差异部分可以通过非特异性宿主防御机制从呼吸道清除生物体的差异来解释。
