Long‐term immune response to Omicron‐specific mRNA vaccination in mice, hamsters, and nonhuman primates
Yi Wu,
Namei Wu,
Xiaoying Jia,
Yan Wu,
Xinghai Zhang,
Yang Liu,
Yuxia Hou,
Yanqiong Shen,
Entao Li,
Wei Wang,
Yucai Wang,
Sandra Chiu
Affiliations
Yi Wu
Department of Laboratory MedicineThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei Anhui P. R. China
Namei Wu
Department of Laboratory MedicineThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei Anhui P. R. China
Xiaoying Jia
State Key Laboratory of Virology Wuhan Institute of Virology Center for Biosafety Mega‐Science Chinese Academy of Sciences Wuhan P. R. China
Yan Wu
State Key Laboratory of Virology Wuhan Institute of Virology Center for Biosafety Mega‐Science Chinese Academy of Sciences Wuhan P. R. China
Xinghai Zhang
State Key Laboratory of Virology Wuhan Institute of Virology Center for Biosafety Mega‐Science Chinese Academy of Sciences Wuhan P. R. China
Yang Liu
State Key Laboratory of Virology Wuhan Institute of Virology Center for Biosafety Mega‐Science Chinese Academy of Sciences Wuhan P. R. China
Yuxia Hou
State Key Laboratory of Virology Wuhan Institute of Virology Center for Biosafety Mega‐Science Chinese Academy of Sciences Wuhan P. R. China
Yanqiong Shen
RNAlfa Biotech Hefei Anhui P. R. China
Entao Li
Department of Laboratory MedicineThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei Anhui P. R. China
Wei Wang
State Key Laboratory of Virology Wuhan Institute of Virology Center for Biosafety Mega‐Science Chinese Academy of Sciences Wuhan P. R. China
Yucai Wang
Division of Life Sciences and Medicine University of Science and Technology of China Hefei Anhui P. R. China
Sandra Chiu
Department of Laboratory MedicineThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei Anhui P. R. China
Abstract Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) Omicron and its subvariants (such as BQ.1, XBB and the latest variants, including XBB.1.16, EG.5, and BA.2.86), as the dominant variants, currently account for almost all new infections in the world due to their high transmissibility and immune escape ability. Omicron‐specific mRNA vaccines showed great potential to protect against Omicron infections. However, whether the vaccine could provide long‐term protection is unknown. Toward this goal, we evaluated the immunogenicity of a preclinical Omicron (BA.1)‐specific mRNA vaccine (SOmicron‐6P) in different animal models. SOmicron‐6P induced the highest levels of antibody titers at 1–2 weeks in different animals after the second dose. Even 9 months after the immunization, we observed modest neutralizing activity against Omicron subvariants in macaques. In addition, immunological memory cells can be rapidly reactivated upon stimulation. SOmicron‐6P at concentrations higher than 10 μg effectively protected hamsters from BA.1 challenge 253 days after the first immunization, which could be attributed to the reactivation of immune systems. In addition, the toxicity tests conducted in rats revealed a highly favorable biosafety profile for SOmicron‐6P, even at high dosages. Our data suggest that the Omicron‐specific mRNA vaccine is highly effective and safe in animal models and provides long‐term immunologic protection against SARS‐CoV‐2 Omicron infections.
