Plasmodium vivax circumsporozoite protein VK210 repeat region (PvCSP VK210)

The Plasmodium vivax circumsporozoite protein (PvCSP) is the most abundant protein on the surface of the sporozoite stage of the malaria parasite and is essential for parasite development and infection of the human host [3, 10]. The VK210 repeat region is the most prevalent allelic variant of the protein's central domain, characterized by the tandemly repeated nonapeptide motif GDRA(A/D)GQPA [3, 14]. This region serves as a primary immunodominant B-cell epitope, making it a critical target for vaccine development and monoclonal antibody-based prophylaxis [1, 6]. Antibodies elicited by vaccines or administered as monoclonal therapies bind to these repeats, effectively neutralizing the sporozoite by inhibiting its motility and preventing its invasion of hepatocytes [11, 12]. However, the high degree of genetic polymorphism and the presence of alternative alleles like VK247 and P. vivax-like necessitate the development of multi-allelic or chimeric vaccine candidates to ensure broad protection [4, 13]. Current research focuses on optimizing the immunogenicity of these repeats using platforms like virus-like particles and identifying potent human monoclonal antibodies for passive immunization [7, 8]. Clinical trials of vaccines like VMP001 have demonstrated the feasibility of targeting this region, although achieving high levels of sterile protection remains a significant challenge [4, 6]. Monitoring antibody titers against specific motifs like the AGDR tetramer serves as a biomarker for vaccine-induced immunity [1, 4]. Overall, the PvCSP VK210 repeat region is a cornerstone of pre-erythrocytic malaria vaccine strategies aimed at blocking the initial stages of infection [10, 13].

Other names

PvCSP VK210Plasmodium vivax CSP VK210VK210 repeat regionCentral repeat region of PvCSP

Binding of antibodies to the repeat region of the circumsporozoite protein on the sporozoite surface, which inhibits parasite motility and prevents the invasion of human hepatocytes.