Measurement of adenine uptake as an in vitro screen for antitrichomonal agents

A semi-automated microdilution test was adapted for the in vitro testing of potential antitrichomonal agents. Washed cell suspensions of the pathogenic protozoan Trichomonas vaginalis were incubated in microtitration plates for 4 h at 37 degrees C in the presence radiolabelled adenine and serial dilutions of the test compounds. After automatic harvesting of the cells onto filter paper discs, the extent of adenine uptake was estimated by scintillation counting. From the dose-response data it was possible to quantify accurately and rapidly the antitrichomonal activity of a range of compounds based on the inhibition of adenine uptake.