Liver stage antigen 3 (LSA-3)

Liver stage antigen 3 (LSA-3) is a 200 kDa protein expressed by Plasmodium falciparum during the sporozoite and liver stages of the parasite life cycle (UniProt: Q8I6U7). It is localized to the surface of sporozoites and the parasitophorous vacuole of infected hepatocytes, serving as a critical target for pre-erythrocytic vaccine development (PubMed: 11159247). LSA-3 is highly conserved across different P. falciparum strains, which is advantageous for a global vaccine candidate (PubMed: 15567131). The protein induces both humoral and cell-mediated immune responses, specifically stimulating IFN-gamma production by T-cells, which is associated with protection against malaria (PubMed: 12433301). Clinical trials have evaluated LSA-3 using long synthetic peptides (LSA3-LSP) and DNA-based platforms, demonstrating safety and immunogenicity, though protective efficacy has varied in human challenge models (PubMed: 21641316). As a therapeutic target, it aims to block the parasite before it reaches the symptomatic blood stage of infection.

Other names

LSA3Plasmodium falciparum liver stage antigen 3PF3D7_0220000

Induction of humoral and cellular immune responses, specifically targeting the pre-erythrocytic stage of Plasmodium falciparum to prevent liver infection and subsequent blood-stage disease (PubMed: 11159247).