Fig. 5

TB activities of the anti-rPb51 sera. a Effect of the antiserum on exflagellation of male gametocytes. Anti-rPb51 sera, or control mouse sera were diluted at 1:5, 1:10 and 1:50 and incubated with gametocytes to quantify exflagellation centres. b Effect of anti-rPb51 sera at 1:5, 1:10 and 1:50 dilutions on P. berghei ookinete formation in vitro. c In vitro development of ookinetes using P. berghei-infected blood of control or rPb51-immunized mice. Infected blood on day 3 post P. berghei infection collected from these two groups of mice were incubated with culture medium (1:10) and parasite stages were counted at 24 h of incubation. d Direct mosquito feeding assay on control and rPb51-immunized mice. For a–d, means were representative of three separate experiments. Error bars indicate mean ± SD. **Indicate significant difference compared with the control sera (P < 0.01)