Baskerville A, Fitzgeorge R B, Gilmour M I, Dowsett A B, Williams A, Featherstone A S
Pathology Division, PHLS Centre for Applied Microbiology and Research, Salisbury, UK.
Br J Exp Pathol. 1988 Dec;69(6):781-92.
Guinea-pigs were exposed for 14 days to an aerosol of titanium dioxide (TiO2) dust to produce macrophage blockade. Groups of the animals were later infected by aerosol with Legionella pneumophila. Histological and ultrastructural studies showed that TiO2 dust alone was inert and non-fibrogenic and even at 6 weeks induced no pathological lesions in the lungs, apart from accumulation of macrophages in interalveolar septa. The macrophage blockade by TiO2 did not alter the animals' susceptibility to Legionnaires' disease nor increase mortality. The blockade was effective in the early stages of the infection and limited multiplication of L. pneumophila in the lungs. Later blood monocytes were recruited into the lungs, where they phagocytosed Legionellae, resulting in lung counts comparable to those of TiO2-free control animals.
将豚鼠暴露于二氧化钛（TiO₂）粉尘气溶胶中14天以产生巨噬细胞阻滞。随后将这些动物分组通过气溶胶感染嗜肺军团菌。组织学和超微结构研究表明，单独的TiO₂粉尘是惰性的且无纤维生成性，即使在6周时，除了肺泡间隔中有巨噬细胞积聚外，肺部也未诱发病理病变。TiO₂造成的巨噬细胞阻滞并未改变动物对军团病的易感性，也未增加死亡率。这种阻滞在感染早期是有效的，限制了嗜肺军团菌在肺部的繁殖。后来血液中的单核细胞被募集到肺部，在那里它们吞噬军团菌，导致肺部菌量与未接触TiO₂的对照动物相当。
