Chimeric lyssavirus glycoproteins with increased immunological potential

Area of Science:

• Virology
• Immunology
• Molecular Biology

Background:

• The rabies virus glycoprotein (G) is crucial for viral entry and immunity.
• It comprises an NH2-terminal (site II) and a COOH-terminal (site III) part, linked by a flexible hinge.
• Understanding the distinct roles of these domains is key for vaccine development.

Purpose of the Study:

• To investigate the structural and immunological functions of the NH2 (site II) and COOH (site III) parts of the rabies virus glycoprotein.
• To assess the efficacy of chimeric G genes in inducing protective immunity against different rabies virus genotypes.

Main Methods:

• Cell transfection and expression of homogeneous and chimeric G genes from various rabies virus genotypes (PV, Mokola, EBL1).
• DNA-based immunization of mice to evaluate antibody responses and T helper cell induction.
• Analysis of antigen transport, folding, and virus-neutralizing antibody production.

Main Results:

• Chimeric G proteins expressing both site II and site III domains were correctly folded and transported.
• These constructs induced virus-neutralizing antibodies against parental viruses.
• The site III part of PV (GT1) effectively presented site II parts from different genotypes and induced T helper cells.
• A specific chimeric plasmid (pGEBL1-PV) broadened protection against multiple European lyssavirus genotypes.

Conclusions:

• Both the NH2 (site II) and COOH (site III) parts of the rabies virus glycoprotein are essential for its correct folding and cellular transport.
• Chimeric G proteins hold significant potential for immunological studies and the development of broad-spectrum, multivalent rabies vaccines.
• The chimeric plasmid pGEBL1-PV demonstrates efficacy against diverse European lyssavirus genotypes.