A novel viral vaccine platform based on engineered transfer RNA

ABSTRACT

In recent years, an increasing number of emerging and remerging virus outbreaks have occurred and the rapid development of vaccines against these viruses has been crucial. Controlling the replication of premature termination codon (PTC)-containing viruses is a promising approach to generate live but replication-defective viruses that can be used for potent vaccines. Here, we used anticodon-engineered transfer RNAs (ACE-tRNAs) as powerful precision switches to control the replication of PTC-containing viruses. We showed that ACE-tRNAs display higher potency of reading through PTCs than genetic code expansion (GCE) technology. Interestingly, ACE-tRNA has a site preference that may influence its read-through efficacy. We further attempted to use ACE-tRNAs as a novel viral vaccine platform. Using a human immunodeficiency virus type 1 (HIV-1) pseudotyped virus as an RNA virus model, we found that ACE-tRNAs display high potency for read-through viral PTCs and precisely control their production. Pseudorabies virus (PRV), a herpesvirus, was used as a DNA virus model. We found that ACE-tRNAs display high potency for reading through viral PTCs and precisely controlling PTC-containing virus replication. In addition, PTC-engineered PRV completely attenuated and lost virulence in mice in vivo, and immunization with PRV containing a PTC elicited a robust immune response and provided complete protection against wild-type PRV challenge. Overall, replication-controllable PTC-containing viruses based on ACE-tRNAs provide a new strategy to rapidly attenuate virus infection and prime robust immune responses. This technology can be used as a platform for rapidly developing viral vaccines in the future.

KEYWORDS:

• Engineered transfer RNA
• PTC virus
• vaccine
• switch
• Pseudorabies virus
• novel vaccine

Acknowledgements

The authors are grateful to Prof. Demin Zhou at Peking University, who kindly provided plasmids related to the orthogonal translation system, pSD31-pylRS, bjmu-12t-zeo, and pSD31-GFP39^TAG. The authors are also grateful to Prof. Xaiomei Wang and Prof. Changjiang Weng at HVRI for their constructive suggestions and assistance. Y.T. conceived the idea. T.W., H.Z., X.C., and Y.T. designed the experiments and wrote the paper. T.W., F.M., G.S., and H.Z. conducted the experiments. F.M., T.W., and Y.T. reviewed and edited the manuscript. All authors have read and agreed to the published version of the manuscript.

Disclosure statement

Yan-Dong Tang and Xue-Hui Cai filed two patents related to this technology.

Ethical approval

All animal experiments were conducted in accordance with the Guide for the Care and Use of Laboratory Animals of the Ministry of Science and Technology of the People’s Republic of China. Animal experiments (Approval number: 210926-02) were conducted in animal biosafety level 2 facilities under the supervision of the Committee on the Ethics of Animal Experiments of the Harbin Veterinary Research Institute of the Chinese Academy of Agricultural Sciences (CAAS).

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This research was supported by the China National Key R&D Program during the 14th Five-year Plan Period [grant number 2022YFD1800300]. This work was supported by grants from the State Key Laboratory of Veterinary Biotechnology of CAAS [SKLVBP201803 to Y-D. Tang; SKLVBP202106 to F. Meng].