GFP expression and flow cytometry analysis of PfMSP1-19Pb8.7 clone in blood-stages.
The same fields were photographed using bright (left panel) and fluorescence microscopy (right panel). Mature schizont stage (A). Early schizont stage (B). Flow cytometry analysis of blood cells obtained from infected mice with asynchronous infections. Per sample, 106 erythrocytes were analyzed. Dot plots of blood cells were obtained from uninfected (upper line) and PfMSP1-19Pb8.7-infected (lower line) mice. For counting the number of infected cells the erythrocyte population was selected by size (forward-scatter (FSC) and side-scatter (SSC)) as shown in the left panel. The center panel shows the relative GFP-fluorescence intensity of cells in the R1 region. Fluorescent erythrocytes were selected from region M2. The right panel shows the dot plot of fluorescence intensity versus the size of cells in R1. Fluorescent erythrocytes were selected in R3, non-fluorescent in R2 (C). Correlation between the parasitemia counted by flow cytometry and the parasitemia counted manually in Giemsa stained blood films (D).