All VAR2CSA single domains were cloned from genomic P. falciparum FCR3 parasite DNA (GenBank accession no. AY372123). Full length var2csa was based on a codon optimized synthetic DNA fragment as described [18] . Gene fragments were cloned into the Baculovirus vector, pAcGP67-A (BD Biosciences) modified to contain a V5 epitope upstream of a histidine tag in the C-terminal end of the constructs. Linearized Bakpak6 baculovirus DNA (BD Biosciences) was co-transfected with pAcGP67-A into Sf9 insect cells for generation of recombinant virus particles. Histidine-tagged recombinant protein was purified on Ni 2+ sepharose columns from the supernatant of baculovirus infected High-Five insect cells using an Ä KTA-express purification system (GE-Healthcare). The full-length protein VAR2CSA (FV2) and the six VAR2CSA DBL-domains were produced corresponding to the following amino acid number in 