Potato virus X coat protein (PVXCP) (PVXCP)

Potato virus X coat protein (PVXCP) is a structural protein from the Potato virus X (PVX) that serves as a potent platform for vaccine development and immunotherapy (UniProt P03310). It is characterized by its ability to form filamentous virus-like particles (VLPs) that display multiple copies of a target antigen, enhancing its visibility to the immune system (Savelyeva et al., Nature Biotechnology, 2001). The primary biological function of PVXCP in a therapeutic context is to act as a molecular adjuvant and carrier that promotes the activation of CD4+ T cells. Upon administration, PVXCP is efficiently internalized by professional antigen-presenting cells (APCs), where it is processed and its peptides are presented via MHC class II molecules (Massa et al., Vaccine, 2007). This presentation triggers a robust CD4+ T-cell response, which provides the necessary help for the activation of B cells and cytotoxic CD8+ T cells. In clinical and preclinical studies, PVXCP-based vaccines have been investigated for their role in treating B-cell malignancies and solid tumors like HER2-positive breast cancer (Giedmo et al., 2020). The protein's inherent immunogenicity helps overcome immune tolerance to self-antigens, a common challenge in cancer vaccinology. While highly effective, a potential challenge includes the development of neutralizing antibodies against the PVXCP scaffold itself, which may impact the efficacy of subsequent doses.

Other names

PVX CPPotato virus X capsid proteinPVX coat protein

PVXCP acts as a highly immunogenic scaffold that is captured by antigen-presenting cells, processed, and presented via MHC class II to CD4+ T cells, thereby providing T-cell help for broader immune activation.