Tomlinson A, Simmons P A, Seal D V, McFadyen A K
Department of Vision Sciences, Glasgow Caledonian University, UK.
Ophthalmology. 2000 Jan;107(1):112-7. doi: 10.1016/s0161-6420(99)00055-x.
Acanthamoeba attachment (adsorption) to hydrogel contact lenses is enhanced by Pseudomonas aeruginosa biofilm. The effect of sodium salicylate on Acanthamoeba attachment to biofilm-coated and uncoated hydrogel lenses was investigated.
Experimental study.
A minimum of 16 replicates were used for each test condition; a control condition using clean lenses without biofilm was included.
Four groups of hydrogel contact lenses (etafilcon A) were pretreated with P. aeruginosa to form a biofilm. In addition, two more groups remained untreated. Quartered lenses of all six groups were then incubated in a suspension of A. castellanii trophozoites. Two batches of lenses had either 3 or 30 mM sodium salicylate added to the bacterial suspension (stage 1 intervention). Two other batches of lenses had salicylate added to the amoebal suspension (stage 2 intervention). One of the batches, which had a stage 1 intervention, had salicylate added at the second stage as well. The remaining batches received no salicylate exposure and included lenses with and without biofilm coating.
The outcome measure in this study was the number of Acanthamoeba trophozoites attached, per square centimeter, to the hydrogel surfaces.
Biofilm coating from P. aeruginosa gave a significantly increased attachment of A. castellanii trophozoites to the contact lens. When introduced at a first (biofilm) stage, second (trophozoite attachment) stage, or with intervention at both stages, 30 mM sodium salicylate reduced amoebal attachment to the hydrogel lens. When applied to both stages and when applied at stage 2 to the biofilm coated contact lenses, 3 mM sodium salicylate reduced amoebal attachment. The 3 mM concentration was not effective for the lower level of amoebae attachment to uncoated (nonbiofilm) lenses.
Sodium salicylate successfully reduced amoebal trophozoite attachment to hydrogel lenses. This was the result of one of the following possibilities or a combination thereof: inhibition of biofilm formation; a direct effect on the amoebae; an alteration in the biofilm-amoebal attachment and resulting modification of the hydrogel lens surface. The results of this study suggest the major action is at stage 2 (on amoebal attachment to lenses) and favors alteration of the biofilm-amoebal attachment mechanism. This study demonstrates salicylate's potential benefit as a component of contact lens care solutions, designed to reduce microbial attachment and the risk of infection.
铜绿假单胞菌生物膜可增强棘阿米巴对水凝胶隐形眼镜的附着（吸附）作用。本研究调查了水杨酸钠对棘阿米巴附着于生物膜包被和未包被的水凝胶镜片的影响。
实验研究。
每个测试条件至少使用16个重复样本；包括一个使用无生物膜的清洁镜片的对照条件。
四组水凝胶隐形眼镜（依他氟康A）用铜绿假单胞菌预处理以形成生物膜。此外，另外两组未进行处理。然后将所有六组的四分之一镜片在卡氏棘阿米巴滋养体悬液中孵育。两批镜片在细菌悬液中添加了3或30 mM水杨酸钠（第一阶段干预）。另外两批镜片在阿米巴悬液中添加了水杨酸钠（第二阶段干预）。其中一批进行了第一阶段干预的镜片在第二阶段也添加了水杨酸钠。其余批次未接触水杨酸钠，包括有和没有生物膜包被的镜片。
本研究的观察指标是每平方厘米附着于水凝胶表面的棘阿米巴滋养体数量。
铜绿假单胞菌形成的生物膜使卡氏棘阿米巴滋养体对隐形眼镜 的附着显著增加。当在第一阶段（生物膜阶段）、第二阶段（滋养体附着阶段）引入，或在两个阶段都进行干预时，30 mM水杨酸钠可减少阿米巴对水凝胶镜片的附着。当在两个阶段都应用，以及在第二阶段应用于生物膜包被的隐形眼镜时，3 mM水杨酸钠可减少阿米巴的附着。3 mM浓度对较低水平的阿米巴附着于未包被（无生物膜）镜片无效。
水杨酸钠成功减少了阿米巴滋养体对水凝胶镜片的附着。这是以下一种或多种可能性的结果：抑制生物膜形成；对阿米巴的直接作用；生物膜 - 阿米巴附着的改变以及水凝胶镜片表面的相应改变。本研究结果表明主要作用发生在第二阶段（对阿米巴附着于镜片），且有利于生物膜 - 阿米巴附着机制的改变。本研究证明了水杨酸盐作为隐形眼镜护理液成分的潜在益处，旨在减少微生物附着和感染风险。
