Resistance of fluorescent-labelled Actinobacillus actinomycetemcomitans strains to phagocytosis and killing by human neutrophils
Resistance of fluorescent-labelled Actinobacillus actinomycetemcomitans strains to phagocytosis and killing by human neutrophils
复制标题
DOI：
10.1111/j.1462-5822.2005.00601.x
复制
发表时间：
2006-01-01
影响因子：
3.4
通讯作者：
Galli, DM
中科院分区：
文献类型：
--
作者：
Permpanich, P;Kowolik, MJ;Galli, DM
中性粒细胞最初是参与宿主防御细菌感染的主要细胞，包括牙周病。侵袭性牙周炎与放线菌有关，放线菌是一种革兰氏阴性嗜热微生物。放线菌引起的感染不被宿主免疫反应解决，尽管在炎症部位积累了中性粒细胞。为了更好地了解自然宿主防御机制在放线菌感染中的作用，利用绿色荧光蛋白基因标记、荧光激活细胞分选和荧光成像等技术，直接评估了这种病原体表型不同菌株与人类中性粒细胞的相互作用。该研究包括临床分离的放线菌属，以自聚集、生物膜相关和等基因浮游变异为代表。获得的数据显示，无论菌株特异性血清型或白毒素产生如何，补体介导的放线菌吞噬作用通常都是低效的。此外，大多数摄入的细菌在暴露于中性粒细胞1小时后仍能存活。有趣的是，摄取抗体活化的细菌导致中性粒细胞的快速细胞死亡。这与补体调理菌的摄入相反，补体调理菌不影响中性粒细胞的活力。本研究中使用的方法提供了可靠的、可重复的关于放线菌的粘附、吞噬和杀伤的结果，当遇到人类中性粒细胞时。
Neutrophils are initially the predominant cells involved in the host defence of bacterial infections, including periodontal disease. Aggressive periodontitis is associated with Actinobacillus actinomycetemcomitans, a Gram-negative capnophilic microorganism. Infections caused by A. actinomycetemcomitans are not resolved by the host immune response despite the accumulation of neutrophils at the site of inflammation. To better understand the role of natural host defence mechanisms in A. actinomycetemcomitans infections, the interaction of phenotypically diverse strains of this pathogen with human neutrophils was assessed directly using techniques such as genetic labelling with the gene for green fluorescent protein, fluorescence-activated cell sorting and fluorescence imaging. The study included clinical isolates of A. actinomycetemcomitans represented by self-aggregating, biofilm-associated and isogenic planktonic variants. Data obtained showed that complement-mediated phagocytosis of A. actinomycetemcomitans was generally inefficient regardless of strain-specific serotype or leukotoxin production. Furthermore, the majority of ingested bacteria remained viable after exposure to neutrophils for 1 h. Interestingly, uptake of antibody-opsonized bacteria resulted in the rapid cell death of neutrophils. This was in contrast to ingestion of complement-opsonized bacteria, which did not affect neutrophil viability. The methods used in this study provided reliable and reproducible results with respect to adherence, phagocytosis and killing of A. actinomycetemcomitans when encountering human neutrophils.