Elucidating the molecular basis for host receptor recognition by recombinantly obtained Plasmodium vivax tryptophan-rich antigens

Host-parasite interactions involved in the process of P. vivax reticulocyte invasion are poorly understood due to the lack of long-term culture methods (in contrast to P. falciparum). Surface antigens of the P. vivax tryptophan-rich antigen (PvTRAg) family are expressed in the early ring or the late schizont stages and have been shown to bind erythrocytes in vitro. Each PvTRAg appears to recognize at least two different host receptors, among them basigin and Band3. By using ex vivo invasion assays coupled to transcriptomic analysis of P. vivax isolates, we have recently demonstrated that Band3 is a P. vivax invasion receptor that binds to PvTRAg38 (and potentially other PvTRAgs). However, the molecular determinants underlying host receptor recognition by PvTRAgs, the functional redundancy in these interactions, and how this relates to subsequent reticulocyte invasion by P. vivax remains unknown. With this RecTRAgs jPPP we aim to establish the molecular basis of PvTRAg38-basigin interaction and its role in invasion. By using transgenic P. knowlesi as a model for P. vivax and producing recombinant PvTRAg38 and basigin, we will thoroughly characterize the interaction of Pv/PkTRAg38 and human basigin and its function during invasion. Results of 􀍞RecTRAgs􀍟 will guide future projects on broader PvTRAg-receptor interactions and its biological function.