Ripollés Daniel, Harouna Saidou, Parrón José A, Arenales Irene, Calvo Miguel, Pérez María D, Sánchez Lourdes
Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Universidad de Zaragoza-CITA , Zaragoza, Spain.
Departamento de Ingenierı́a Agroindustrial, Universidad Autónoma de Chapingo , Texcoco, México.
J Agric Food Chem. 2017 Feb 8;65(5):1043-1050. doi: 10.1021/acs.jafc.6b04971. Epub 2017 Jan 30.
Cronobacter sakazakii is a foodborne pathogen that has been associated with severe infections, mainly in neonates. The binding of this bacterium to host cell surfaces represents the first step in the pathogenesis of disease. An ELISA-based assay has been developed using a polyclonal antiserum against C. sakazakii to determine its adhesion to Caco-2 cells. The antiserum used recognized many of the outer membrane proteins of C. sakazakii. A positive correlation was found between the absorbance values obtained by ELISA and the number of bacteria adhered to cells determined by plate counting. The inhibitory effect on bacterial adhesion to cells observed with some dairy products was concentration-dependent. Commercial buttermilk caused the maximal reduction of the adhesion percentage (33.0 ± 5.07) at the highest concentration assayed (20 mg/mL), followed by butter serum (31.9 ± 5.36), skim milk (30.4 ± 5.07), and raw buttermilk (25.6 ± 3.80). In some cases, significant differences (p < 0.05) were found in the inhibition exerted by the different products evaluated. The results obtained in this study demonstrate that dairy products contain some components with the ability to inhibit the adhesion of C. sakazakii to Caco-2 cells.
阪崎肠杆菌是一种食源性病原体，主要与新生儿的严重感染有关。这种细菌与宿主细胞表面的结合是疾病发病机制的第一步。已开发出一种基于酶联免疫吸附测定（ELISA）的检测方法，使用针对阪崎肠杆菌的多克隆抗血清来确定其对Caco-2细胞的粘附情况。所使用的抗血清识别阪崎肠杆菌的许多外膜蛋白。通过ELISA获得的吸光度值与通过平板计数确定的粘附到细胞上的细菌数量之间存在正相关。一些乳制品对细菌粘附到细胞的抑制作用呈浓度依赖性。在测定的最高浓度（20 mg/mL）下，市售酪乳导致粘附百分比的最大降低（33.0±5.07），其次是黄油乳清（31.9±5.36）、脱脂乳（30.4±5.07）和生酪乳（25.6±3.80）。在某些情况下，在所评估的不同产品所产生的抑制作用中发现了显著差异（p<0.05）。本研究获得的结果表明，乳制品含有一些能够抑制阪崎肠杆菌粘附到Caco-2细胞的成分。
