A Self-Assembled Viral Protein VP1 Induces Protective Immunity Against Coxsackievirus B3 (CVB3) Lethal Challenges in Balb/c Mice Model

Epidemiological studies have proven that coxsackievirus B3 (CVB3) is the major virus that cause acute and chronic viral myocarditis and cardiomyopathy. Currently, there are no antiviral therapeutic drugs or vaccines to be used as clinical therapeutic or vaccine. Virus-like particles (VLP) based vaccines offer a safe and effective vaccine platforms because of their structural similarity to native viruses, but lack viral genetic material and therefore considered a better immunogens. The viral capsid protein VP1 of CVB3 is the most immunogen viral peptide, providing opportunities for its use in designing VLP-based vaccines or immunodiagnostic reagents. In the present study, we developed and characterized a CVB3 vaccine candidate based on a self-assembly of the major immunogenic viral protein VP1 of CVB3 wild type strain. We assessed its induced humoral and cellular immune responses and then we evaluated its protective immunity against pathogenic CVB3 strain challenges in Balb/c mice model. Neutralizing specific antibodies and Interferon gamma (INF-γ) production were determined in sera of both prime and prime-boosted immunized mice with VLP vaccine candidate. Our results demonstrated that VLP generated by VP1 self-assembled and expressed in eukaryotic insect cell baculovirus vector system elicited potent humoral and cellular immune responses, protecting Balb/c mice from lethal challenges. Hence, the produced VLP based on the self-assembly of VP1 is a promising and potential vaccine candidate against CVB3 natural infections.