Application of an enzyme immunoassay to monitor bacterial binding and to measure inhibition of binding to different types of solid surfaces

We describe the application of an enzyme immunoassay (EIA) for detecting bacteria bound to a solid surface. Different Yersinia enterocolitica and Escherichia coli strains, expressing the YadA protein, type 1 or type P fimbriae were used as models for this study. The assay was used to detect bacteria bound to fixed tissues or to glass slides coated with extracellular matrix molecules (collagen, laminin or fibronectin). E. coli specific antiserum (B357, Dakopatts, Glostrup, Denmark) and peroxidase conjugated antiserum (P217) were used to detect all E. coli strains used in the study. The bacterial binding could be monitored with a linear detection range between 10⁵ and 10⁸ bacteria. Most importantly, dose dependent inhibition of bacterial binding by soluble extracellular matrix molecules could be measured.