The merozoite recombinant proteins are immunoreactive against hyperimmune sera. The immunoreactivity of the recombinant P. falciparum merozoite proteins was tested using pooled sera from malaria-exposed Malawian adults (red bar) or malaria-naïve adults (green bar). The reduced immunoreactivity of immune sera to heat-denatured antigens (blue bar) demonstrates the presence of heat-labile (conformational) epitopes. All proteins except one (MSRP4) were identified as being immunoreactive as assessed by immunoreactivity >3 SD above negative control (green bar). AMA-1 and Cd4 were used as the positive and negative control, respectively. Data points are shown as mean ± s.d.; n = 3.