Figure 1.

Serum antibody endpoint titres and sub‐fragment recognition. Immunizations, rest periods, blood collection and terminal end‐points are depicted in (a). Each independent immunization group (A to F) consisted of wild‐type (WT) and knockout (KO) mice immunized with non‐reduced (NR) and reduced/alkylated (RA) Pfs48/45 proteins, n = 5 mice for each form of immunogen. While B and F groups followed a very similar immunization schedule, they were totally independent of each other and used for different assays. Individual mouse serum collected after each immunization was tested by ELISA method for recognition of (b) NR‐Pfs48/45 coating antigen and (c) RA‐Pfs48/45 coating antigen. End‐point titres were defined as the last serum dilution found positive above pre‐immune sera mean + 3SD, and were averaged for responding mice in each group. Symbols represent average end‐point for each immunization group, for bleeds collected after the second booster immunization. Statistical analysis was performed using one‐way analysis of variance to compare end‐point titres across groups for each coating antigen and each immunogen. (d) Schematic representation of the amino acid boundaries for Pfs48/45 fragments and synthetic peptides (P1–P38), corresponding to the full‐length Pfs48/45 sequence. (e) Individual mice sera after second booster immunization were analysed (dilution 1 : 500) by Western blotting analysis. The recognition of individual Pfs48/45 fragments was tallied for each group, reported as percent responding mice, and presented according to immunogen; non‐reduced (NR) and reduced/alkylated (RA) Pfs48/45 protein.