A RAPID COLORIMETRIC ASSAY FOR DETERMINATION OF LEUKOCYTE-MEDIATED INHIBITION OF MYCELIAL GROWTH OF CANDIDA-ALBICANS

A staining method with crystal violet (CV) was demonstrated to be usef ul for a simple, quick and objective assessment of in vitro growth inh ibitory activity of leukocytes against Candida albicans cells. Candida cells incubated with murine neutrophils or macrophages for 14 hr in m icrowells were stained with CV and, after washing with 0.25% sodium do decyl sulfate (SDS), treated with isopropanol containing HCl (0.04 N) to extract Candida cell-bound CV. Then the absorbance at 590 nm of the isopropanol extract was photometrically measured. The results showed that the photometrical absorbance was proportional to the amount of H- 3-glucose taken up by C. albicans cells, which reflected the number of viable Candida cells.