Affiliations
- Yunnan Key Laboratory of Vaccine Research and Development for Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medicine Sciences & Peking Union Medical College, Kunming 650118, China.
PMID: 36992107 PMCID: PMC10059745 DOI: 10.3390/vaccines11030524
Abstract
Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike (S) protein is a crucial viral antigenic protein that enables the production of neutralizing antibodies, while the roles of other structural proteins, including the membrane (M), nucleocapsid (N), and envelope (E) proteins, in antiviral immunity remain unclear.
Methods: In this study, S1, S2, M, N, and E proteins were expressed in 16HBE cells to evaluate their role in the innate immune response. Additionally, PBMCs from mice immunized with two doses of inactivated or mRNA vaccines were used to assess specific T-cell immune responses to these proteins.
Results: Viral structural proteins activated innate immune responses and elicited specific T-cell responses in vaccinated mice. However, T-cell responses against M, N, and E proteins were insufficient to enhance the level of humoral immunity compared to Spike proteins.
Conclusion: While structural proteins can induce specific T-cell responses, they do not significantly contribute to improving humoral immunity levels, highlighting the need for targeted vaccine strategies.
Keywords:SARS-CoV-2; humoral immunity; innate immune response; specific T-cell response; structural protein.
