Measurement of growth inhibitory activity of antibodies and anti-malarial drugs using GFP fluorescent parasites. Comparison between the GFP transfected PcPHG and PfPHG lines and the parental parasites (PcMEGF and PfM3', respectively) of growth-inhibitory activity of (A) PcMSP1-19 specific rabbit antisera and (B) PfMSP1-19 specific rabbit antisera. Results represent data from three independent two cycle growth assays with samples tested at 1 in 10 dilution. Growth is expressed as a percentage of controls (sera from non-exposed Australian residents) and values represent means with SEM. Inhibition of the PfPHG parasite line by (C) chloroquine and (D) quinine in a one cycle growth assay. Parasitaemia was measured by flow cytometry using ring stage GFP fluorescence, late trophozoite stage GFP fluorescence or late trophozoite stage EtBr fluorescence. Growth is expressed as a percentage of PBS control.