The adherence of Giardia lamblia trophozoites to nylon fibre microcolumns: effect of temperature, fluoride, cyanide and metronidazole.

A simple rapid method for the measurement of adherence of Giardia lamblia trophozoites is described. Microcolumns are prepared from 10 mg amounts of nylon fibre packed into 100 microliter size disposable pipette tips. The kinetics show that 30 min is the optimum contact time for the experiments. Maximum adherence occurred at 37 degrees C, minimal at 4 degrees C, and intermediate at 25 degrees C, suggesting that adherence is an energy-dependent process. Adherence was fluoride-sensitive but cyanide-insensitive, suggesting that this parasite derives its energy from the glycolytic pathway, and not the oxidative pathway. Metronidazole, one of the mainstays for chemotherapy of giardiasis, produced significant inhibition of adherence at 10 micrograms/ml and 100 micrograms/ml concentrations after one hour pre-incubation.