Bjarnsholt Thomas, Jensen Peter Østrup, Fiandaca Mark J, Pedersen Jette, Hansen Christine Rønne, Andersen Claus Bøgelund, Pressler Tacjana, Givskov Michael, Høiby Niels
Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Denmark.
Pediatr Pulmonol. 2009 Jun;44(6):547-58. doi: 10.1002/ppul.21011.
The present study was undertaken to investigate the appearance and location of Pseudomonas aeruginosa in the cystic fibrosis (CF) lung and in sputum. Samples include preserved tissues of CF patients who died due to chronic P. aeruginosa lung infection prior to the advent of intensive antibiotic therapy, explanted lungs from 3 intensively treated chronically P. aeruginosa infected CF patients and routine sputum from 77 chronically P. aeruginosa infected CF patients. All samples were investigated microscopically using hematoxylin-eosin (HE), Gram and alcian-blue stain, PNA FISH and immunofluorescence for alginate.Investigation of the preserved tissues revealed that prior to aggressive antibiotic therapy, P. aeruginosa infection and destruction of the CF lung correlated with the occurrence of mucoid (alginate) bacteria present in aggregating structures surrounded by pronounced polymorphonuclear-leukocyte (PMN) inflammation in the respiratory zone (9/9). Non-mucoid bacteria were not observed here, and rarely in the conductive zone (1/9). However, in the explanted lungs, the P. aeruginosa aggregates were also mucoid but in contrast to the autopsies, they were very rare in the respiratory zone but abundant in the sputum of the conductive zone (3/3), which also contained abundances of PMNs (3/3). Non-mucoid and planktonic P. aeruginosa were also observed here (3/3).In conclusion, the present intensive antibiotic therapy of chronic P. aeruginosa infections, at the Copenhagen CF Centre, seems to restrain but not eradicate the bacteria from the conductive zone, whereas the remaining healthy respiratory zone appears to be protected, for a long period, from massive biofilm infection. This strongly suggests that the conductive zone serves as a bacterial reservoir where the bacteria are organized in mucoid biofilms within the mucus, protected against antibiotics and host defenses.
本研究旨在调查铜绿假单胞菌在囊性纤维化（CF）肺部及痰液中的表现和位置。样本包括在强化抗生素治疗出现之前因慢性铜绿假单胞菌肺部感染死亡的CF患者的保存组织、3例接受强化治疗的慢性铜绿假单胞菌感染的CF患者的离体肺以及77例慢性铜绿假单胞菌感染的CF患者的常规痰液。所有样本均使用苏木精-伊红（HE）染色、革兰氏染色和阿尔辛蓝染色、肽核酸荧光原位杂交（PNA FISH）以及藻酸盐免疫荧光进行显微镜检查。对保存组织的研究显示，在积极的抗生素治疗之前，铜绿假单胞菌感染及CF肺部的破坏与呼吸道区域中存在于由明显的多形核白细胞（PMN）炎症包围的聚集结构中的黏液样（藻酸盐）细菌的出现相关（9/9）。此处未观察到非黏液样细菌，在传导区域也很少见（1/9）。然而，在离体肺中，铜绿假单胞菌聚集体也是黏液样的，但与尸检情况相反，它们在呼吸道区域非常罕见，而在传导区域的痰液中大量存在（3/3），其中也含有大量的PMN（3/3）。此处还观察到了非黏液样和浮游的铜绿假单胞菌（3/3）。总之，哥本哈根CF中心目前对慢性铜绿假单胞菌感染的强化抗生素治疗似乎抑制了但并未从传导区域根除该细菌，而其余健康的呼吸道区域似乎在很长一段时间内受到保护，免受大量生物膜感染。这强烈表明传导区域充当了细菌储存库，细菌在黏液中形成黏液样生物膜，从而免受抗生素和宿主防御机制的影响。
