持续性根尖周炎优势菌粪肠球菌生物膜形成能力的体外研究

摘要

目的：比较持续性根尖周炎优势细菌粪肠球菌( Enterococcus faecalis,E． faecalis)标准菌株与临床菌株生物膜体外形成能力。方法 E． faecalis 标准菌株 ATCC 29212及持续性根尖周炎分离的 E． faecalis 临床株lcl1709,体外形成生物膜,采用激光扫描共聚焦荧光显微镜(LSCM)观察并对比在12、24、36、48h时2种生物膜形成面积；使用96微孔板结晶紫染色法检测并比较在12、24、36、48h时两者生物膜形成量。结果 ATCC 29212菌株培养12、24、36、48h在离体牙根尖表面生物膜形成面积(μm2)分别为47．577±45．221,206．935±122．596,558．782±330．877,1865．023±702．539；lcl1709的为62．227±33．040,461．578±285．281,1211．077±515．262,2632．515±1332．914。36h与48h lcl1709形成的生物膜面积显著高于ATCC 29212(P<0．05)。12、24、36、48h的生物膜OD590值ATCC 29212菌株分别为0．048±0．001,0．130±0．025,0．148±0．022,0．137±0．021；lcl1709菌株分别为0．096±0．029,0．162±0．015,0．201±0．042,0．235±0．078。 lcl1709生物膜OD590值显著高于ATCC 29212(P<0．05),随时间延长,各组OD590值显著增大( P<0．05)。结论 E． faecalis可形成生物膜,持续性根尖周炎分离的E． faecalis菌株生物膜形成能力强于标准菌株,可能与其致病性密切相关。%Objective To compare the biofilm forming ability of Enterococcus faecalis ( E. faecalis ) between standard strains and isolated strains from clinical persistent periodontitis patient. Methods The E. faecalis standard strain ATCC 29212 and the clinical strain from persistent periodontitis lcl1709 were cultured, the biofilm formation model in vitro was established, and the biofilm observed by laser scanning confocal microscopy (LSCM) at 12h, 24h, 36h, 48h and the biofilm area was compared between ATCC29212 and lcl1709 at each time point. The biofilm quantity was compared by staining the biofilm formed in 96 well by crystal violet at 12h, 24h, 36h, and 48h. Results At 12h, 24h, 36h and 48h, the areas of biofilm formed on extracted teeth apical surface by ATCC29212 were 47. 577 ± 45. 221,206. 935 ± 122. 596, 558. 782 ±330. 877,1865. 023 ± 702. 539(μm2), by lcl1709 were 62. 227 ± 33. 040,461. 578 ± 285. 281,1211. 077 ± 515. 262,2632. 515 ±1332. 914(μm2),respectively. At 36h and 48h, the biofilm area of lcl1709 was significantly larger than that of ATCC29212(P<0. 05). OD590 values of ATCC29121were 0. 048 ±0. 001,0. 130 ±0. 025,0. 148 ±0. 022,0. 137 ± 0. 021 and OD590 values of lcl1709 were 0. 096 ± 0. 029,0. 162 ± 0. 015,0. 201 ± 0. 042,0. 235 ± 0. 078, respectively. At 48h, the value of lcl1709 was significantly higher than that of ATCC29212 ( P <0. 05 ) . Conclusion E. faecalis strain lcl1709 has stronger ability on biofilm formation than ATCC29212.