A simple technique useful for clinical laboratory testing for invasive potential applied to Bacteroides fragilis

A simple technique using fluorescent microscopy examines the association between Bacteroides fragilis and different types of tissue cells (epithelial, fibroblast, osteoblast). Through this stepwise intracellular staining and extracellular quenching some latent signs of invasive quality may be exhibited. The bacteria are incubated with monolayers of tissue cells, and the reactions immediately visualized after staining with acridine orange and masking by crystal violet. Intact bacterial rods exhibit a greenish hue which will reveal their location within the tissue cells but varies depending on tissue cell type. This direct means of testing for invasive potential applied to B. fragilis relies on the use of a readily available clinical tool.