A method for the enumeration of bacterial adhesion to epithelial cells using image analysis

Area of Science:

• Microbiology
• Biomedical Engineering
• Cell Biology

Background:

• Bacterial attachment to host cells is crucial for infection pathogenesis.
• Accurate quantification of bacterial adhesion is essential for understanding host-pathogen interactions.
• Staphylococcus epidermidis is a common opportunistic pathogen.

Purpose of the Study:

• To develop and validate a computerised image analysis method for enumerating Staphylococcus epidermidis attachment to HEp-2 cell monolayers.
• To compare the efficiency and accuracy of the computerised method with manual counting.
• To assess the potential of this method for evaluating bacterial attachment to various host tissues.

Main Methods:

• Utilisation of computerised image analysis for bacterial enumeration.
• Employing a differential staining technique for enhanced bacterial visualization.
• Implementing an image processing algorithm involving subtraction of out-of-focus images.
• Using a particle counting routine for rapid quantification.
• Comparison with manual counting methods.

Main Results:

• The computerised image analysis method allowed for rapid and reproducible enumeration of Staphylococcus epidermidis attachment.
• The technique facilitated counting over 700 bacteria per field at 500x magnification.
• The computerised programme demonstrated favourable comparison with manual counting.
• The method provided objective and morphologically discriminatory results.

Conclusions:

• Computerised image analysis provides a rapid, objective, and reproducible method for quantifying bacterial attachment.
• This technique is a valuable tool for studying host-pathogen interactions, specifically bacterial adhesion.
• The developed method has potential applications in evaluating bacterial adhesion to diverse biological tissues.