Plasmodium falciparum Thrombospondin-Related Adhesion Protein (TRAP) (PfTRAP)

Plasmodium falciparum Thrombospondin-Related Adhesion Protein (TRAP), also known as Sporozoite Surface Protein 2 (SSP2), is a type I transmembrane protein essential for the life cycle of the malaria parasite (UniProt P17072). It is primarily expressed on the surface of sporozoites and is localized within the micronemes, where it plays a pivotal role in gliding motility and the invasion of host hepatocytes (PubMed: 21364684). The ME-TRAP construct is a recombinant vaccine antigen that fuses a string of multiple T-cell epitopes (ME) from various P. falciparum antigens to the TRAP protein to enhance immunogenicity (PubMed: 23575490). This construct is typically utilized in heterologous prime-boost vaccination strategies using viral vectors like Chimpanzee Adenovirus 63 (ChAd63) and Modified Vaccinia virus Ankara (MVA) (PubMed: 25635829). The primary mechanism of action involves the induction of robust cellular immune responses, specifically targeting CD8+ and CD4+ T cells to eliminate infected liver-stage hepatocytes before the onset of clinical symptoms. Clinical trials have demonstrated that while the ME-TRAP vaccines are safe and highly immunogenic, achieving consistent and high-level protective efficacy in diverse populations remains a significant challenge (PubMed: 26230967). Consequently, TRAP remains a major focus for pre-erythrocytic vaccine development aimed at malaria eradication.

Other names

Sporozoite Surface Protein 2SSP2Thrombospondin-related anonymous proteinME-TRAP

Induction of a T-cell mediated immune response against the pre-erythrocytic stage of the malaria parasite, specifically utilizing viral vectors to prime and boost CD8+ and CD4+ T cells that recognize and destroy Plasmodium-infected hepatocytes.