Effect of different carbohydrates on the binding of P. berghei ookinetes to methanol-fixed An. stephensi 43 cells. Numbers of cells per ml of culture were estimated using a haemocytometer. 300,000 cells were added to each microwell, allowed to settle, then fixed with a 30 s treatment with methanol. 20,000 ookinetes in culture were added to each well and incubated in the presence or absence of carbohydrates for 6 h at 19°C. Following a washing step, 100 μl of PBS and 10 μl of MTT was added and the plates incubated for a further 4 h at 37°C. Plates were then read at 570 and 620 nm. Data shown are representative of three assays carried out. Plate readings were zeroed to a PBS blank. Shading indicates wells where ookinetes were added. ** Ookinete binding to cells was significantly higher than the control of cells alone (p < 0.01; One-way ANOVA, Dunnett's post hoc test). Data +/- SEM (n = 5-6). Figure 7A: Binding to cells alone, and GlcNAc at 0, 12.5, 50 and 250 mM. Figure 7B: Binding to cells alone, and GalNAc at 0, 12.5, 50 and 250 mM. Figure 7C: Binding to cells alone, and Galactose at 0, 12.5, 50 and 250 mM.