This technology relates to a malaria vaccine composed of a protein complex of Apical Membrane Antigen (AMA1) and rhoptry neck protein 2 (RON2) with an adjuvant. AMA1 is a crucial component of the Plasmodium invasion machinery and is a leading candidate for antimalarial vaccine development. AMA1-based vaccines have shown ability to block red cell invasion in in vitro assays, but protection has so far not translated to in vivo human infections. NIAID investigators have demonstrated that interaction between AMA1 and RON2 (or peptide thereof) is essential for malaria parasites to successfully enter human red blood cells (RBCs). Vaccination with un-complexed AMA1 and RON2 did not protect against lethal malaria. However, vaccination with a pre-formed AMA1-RON2 complex, highlighted in this technology, produced antibodies that protected against lethal malaria in an in vivo mouse model (P. yoelli) and blocked the entry of human malaria parasites into RBCs in vitro. Additionally, the inhibitory antibody response induced by the AMA1-RON2 complex was greater than AMA1 alone or when AMA1 and RON2 proteins were administered in a un-complexed form.

Immunization using the AMA1-RON2 complex of this technology represents a candidate for an effective malaria vaccine against multiple Plasmodium species.