A live-attenuated SARS-CoV-2 vaccine candidate with accessory protein deletions

Yang Liu, Xianwen Zhang, Jianying Liu, Hongjie Xia, Jing Zou, Antonio E. Muruato, Sivakumar Periasamy, Chaitanya Kurhade, Jessica Plante, Nathen E. Bopp, Birte Kalveram, Alexander Bukreyev, Ping Ren, Tian Wang, Vineet D. Menachery, Kenneth S. Plante, Xuping Xie, Scott C. Weaver, Pei-Yong Shi

Research output: Contribution to journalArticlepeer-review

43 Scopus citations


We report a live-attenuated SARS-CoV-2 vaccine candidate with (i) re-engineered viral transcription regulator sequences and (ii) deleted open-reading-frames (ORF) 3, 6, 7, and 8 (∆3678). The ∆3678 virus replicates about 7,500-fold lower than wild-type SARS-CoV-2 on primary human airway cultures, but restores its replication on interferon-deficient Vero-E6 cells that are approved for vaccine production. The ∆3678 virus is highly attenuated in both hamster and K18-hACE2 mouse models. A single-dose immunization of the ∆3678 virus protects hamsters from wild-type virus challenge and transmission. Among the deleted ORFs in the ∆3678 virus, ORF3a accounts for the most attenuation through antagonizing STAT1 phosphorylation during type-I interferon signaling. We also developed an mNeonGreen reporter ∆3678 virus for high-throughput neutralization and antiviral testing. Altogether, the results suggest that ∆3678 SARS-CoV-2 may serve as a live-attenuated vaccine candidate and a research tool for potential biosafety level-2 use.

Original languageEnglish (US)
Article number4337
JournalNature communications
Issue number1
StatePublished - Dec 2022

ASJC Scopus subject areas

  • General Chemistry
  • General Biochemistry, Genetics and Molecular Biology
  • General Physics and Astronomy


Dive into the research topics of 'A live-attenuated SARS-CoV-2 vaccine candidate with accessory protein deletions'. Together they form a unique fingerprint.

Cite this