A replication-defective tick-borne encephalitis virus generated by NS1 trans-complementation confers robust...

Area of Science:

• Virology
• Vaccinology
• Public Health

Background:

• Tick-borne encephalitis virus (TBEV) causes severe neurological disease globally.
• Developing safe and effective TBEV vaccines is a critical public health priority.

Purpose of the Study:

• To construct and evaluate a novel replication-defective TBEV vaccine candidate using an NS1 trans-complementation platform.
• To assess the safety and immunogenicity of the TBEV-ΔNS1 vaccine in a mouse model.

Main Methods:

• A replication-defective TBEV (TBEV-ΔNS1) was generated using a BHK-21 cell line expressing Omsk hemorrhagic fever virus (OHFV) NS1.
• The genetic stability and safety of TBEV-ΔNS1 were confirmed through cell culture and mouse studies.
• Immunogenicity and protective efficacy were evaluated in ICR mice challenged with wild-type TBEV.

Main Results:

• TBEV-ΔNS1 was successfully constructed and confirmed to be replication-defective.
• High-dose administration of TBEV-ΔNS1 was safe in mice, inducing no clinical symptoms.
• A single immunization with TBEV-ΔNS1 conferred complete protection against lethal TBEV challenge, correlated with robust humoral and cellular immunity.

Conclusions:

• The NS1 trans-complementation platform is a viable strategy for developing safe and effective TBEV vaccines.
• TBEV-ΔNS1 demonstrates significant potential as a vaccine candidate for preventing TBEV infection.