In Vitro Selection of Plasmodium Falciparum Lines Resistant to Dihydrofolate-Reductase Inhibitors and Cross Resistance Studies

Genome comparison of progressively drug resistant Plasmodium falciparum lines derived from drug sensitive clone

“…In the present in vitro selection of drug resistant parasites, resistance to pyrimethamine developed much faster and stronger compared to cycloguanil or sulfadoxine. In 348 days continuous cultivation under pyrimethamine selection there was 2400-fold increase in IC 50 value to pyrimethamine whereas only 75-fold decrease in sensitivity to cycloguanil was registered in 351 days cultivation under cycloguanil selection pressure (Bhasin & Nair 1996). There was 35-fold decrease in sensitivity to sulfadoxine in 555 days.…”

“…This protocol for selection of progressively sulfadoxine resistant parasites was repeated for each of the subsequent rounds. Selection procedure for increased DHFR inhibitor resistance has been described by Bhasin and Nair (1996).…”