Fig. 2
Oocyst and sporozoite formation of two chimeric P. falciparum parasite lines (pf-pvcsp) and a PfCSP knockout line (PfΔcsp). a Light microscope pictures of oocysts at day 10 after feeding gametocytes to Anopheles stephensi mosquitoes. Upper panel pf-pvcsp and wild type P. falciparum (WT) oocyst in which sporozoite formation occurs (see Additional file 5 for pictures of pf-pvcsp oocyst that degenerate before sporozoite formation). No sporozoite formation was observed in PfΔcsp oocysts. Scale bar, 20 µm. Lower panel: free pf-pvcsp sporozoites that are released from oocysts by application of force to oocysts in dissected midguts. Scale bar, 20 µm. b Percentage of degenerated oocyst in An. stephensi mosquitoes (n = 5) at day 10 after feeding (**P = 0.0035, ***P = <0.0001; unpaired T-test)