The influence of post-filtration washing on the in vitro assay of Candida albicans adherence to human buccal epithelial cells.

A simple in vitro assay technique was used to determine the effect of post-filtration washing on the adherence of C. albicans (NCPF 3736) to human buccal epithelial cells (BEC). Washing was carried out with a range of volumes of phosphate buffered saline (PBS), viz. 0, 5, 10 and 20 ml, at a standard flow rate. Both the number of C. albicans adherent to BEC and the percentage of BEC with adherent C. albicans were significantly decreased (p < 0.001 for each of these measures) after washing with 5 ml PBS. Further increases in the volume of PBS did not significantly decrease either measure of adherence. These data indicate that only a small volume of PBS, 5 ml, is required to achieve the removal of non-adherent C. albicans from the surface of BEC. The result of the adherence assay is not significantly affected by increasing the volume of PBS used. It is concluded that considerable savings in time may be made through using only a small (5 ml) volume of washing buffer at a standard flow rate.