Balotescu Carmen, Israil Anca-Michaela, Lazăr Veronica, Cernat Ramona, Petrache Lia-Mara, Dinu Cristina
I.N.C.D.M.I. Cantacuzino, Bucureşti.
Bacteriol Virusol Parazitol Epidemiol. 2002 Jul-Dec;47(3-4):131-5.
Bacterial adherence to the cellular substrate (skin and mucosa) represents a precondition of infectious pathology. It was demonstrated that bacteria which adhere and form biofilms on catheters and other inert materials used in medicine are resistant to the therapeutic antibiotic concentrations being protected by the biofilm mathrix and generating severe and hard to treat infections. There are only few studies on the influence of antibiotics on the bacterial adhesins synthesis and bacterial adherence to the cellular substrate. The purpose of this study was to investigate the influence of subinhibitory concentrations of antibiotics on adherence capacity of Listeria monocytogenes, Vibrio cholerae and Aeromonas hydrophyla to the cellular substrate represented by HEp-2 cells. Suspensions (approximately 10(10) cells/ml) of bacterial cultures developed on solid media were incubated for 30 minutes in the presence of subinhibitory concentrations of penicillin, ampicillin, amoxicilin with clavulanic acid, ceftazidim, norfloxacin, kanamycin, chloramphenicole and vancomycin. Study of bacterial adherence to the cellular substrate was done by Cravioto's modified method. The quantitative evaluation of adherence/invasion capacity of bacterial suspensions pretreated with antibiotics was done by comparing the adherence/invasion index with controls without antibiotics. Penicillin, amoxicillin with clavulanic acid and vancomycin have significantly stimulated the adherence of Listeria monocytogenes strain and inhibited the adherence of Vibrio cholerae and Aeromonas hydrophyla strains. Ampicillin and chloramphenicole exhibited no significant effect on bacterial adherence capacity. The influence of kanamycin, ceftazidim and norfloxacin could not be interpreted due to the occurrence of a severe cytotoxic effect manifested by cell monolayer detaching, probably due to the action of antibiotic suspensions or to the increase of bacterial virulence under the selective pressure of the antibiotic.
细菌对细胞底物（皮肤和黏膜）的黏附是感染性病理的一个先决条件。已证明，在医学中使用的导管和其他惰性材料上黏附并形成生物膜的细菌对治疗性抗生素浓度具有抗性，生物膜基质会保护它们，从而引发严重且难以治疗的感染。关于抗生素对细菌黏附素合成以及细菌对细胞底物黏附的影响的研究很少。本研究的目的是调查亚抑菌浓度的抗生素对单核细胞增生李斯特菌、霍乱弧菌和嗜水气单胞菌黏附到以HEp - 2细胞为代表的细胞底物上的能力的影响。在固体培养基上培养的细菌培养物悬液（约10¹⁰个细胞/毫升）在亚抑菌浓度的青霉素、氨苄西林、阿莫西林克拉维酸、头孢他啶、诺氟沙星、卡那霉素、氯霉素和万古霉素存在下孵育30分钟。通过Cravioto改良方法研究细菌对细胞底物的黏附。通过将经抗生素预处理的细菌悬液的黏附/侵袭指数与未用抗生素的对照进行比较，对其黏附/侵袭能力进行定量评估。青霉素、阿莫西林克拉维酸和万古霉素显著刺激了单核细胞增生李斯特菌菌株的黏附，并抑制了霍乱弧菌和嗜水气单胞菌菌株的黏附。氨苄西林和氯霉素对细菌黏附能力无显著影响。由于出现了细胞单层脱落所表现出的严重细胞毒性作用，可能是由于抗生素悬液的作用或在抗生素选择压力下细菌毒力的增加，因此无法解释卡那霉素、头孢他啶和诺氟沙星的影响。
