biostudies-literatureKe QNational Key Research and Development Program of China113279https://www.ebi.ac.uk/biostudies/studies/S-EPMC9075978biostudies-literatureUnknown506The glycosylated receptor-binding domain (glycoRBD) of SARS-CoV-2 can induce protective neutralizing antibodies to function as a vaccine. However, it is unclear whether vaccines using non-glycosylated RBD (non-glycoRBD) can induce protective immunity. Here, we report the efficacy of a SARS-CoV-2 non-glycoRBD vaccine produced by prokaryotic system in mice. The recombinant non-glycoRBD protein was overexpressed in Escherichia coli in the form of inclusion bodies, and was obtained after renaturation and three-step purification. From HPLC analysis, the purity of the RBD was 99%. Additionally, angiotensin converting enzyme 2 (ACE2)-binding assays revealed that E.coli-derived non-glycoRBD had binding activity consistent with glycoRBD. The RBD was formulated with CpG ODN and Al(OH)₃ adJournal of immunological methodsNon-glycosylated SARS-CoV-2 RBD elicited a robust neutralizing antibody response in mice.PMC90759782020YFC0841400–008Wu JSun PMi TWang TKe QLiu BXu HfalseNon-glycosylated SARS-CoV-2 RBD elicited a robust neutralizing antibody response in mice.The glycosylated receptor-binding domain (glycoRBD) of SARS-CoV-2 can induce protective neutralizing antibodies to function as a vaccine. However, it is unclear whether vaccines using non-glycosylated RBD (non-glycoRBD) can induce protective immunity. Here, we report the efficacy of a SARS-CoV-2 non-glycoRBD vaccine produced by prokaryotic system in mice. The recombinant non-glycoRBD protein was overexpressed in Escherichia coli in the form of inclusion bodies, and was obtained after renaturation and three-step purification. From HPLC analysis, the purity of the RBD was 99%. Additionally, angiotensin converting enzyme 2 (ACE2)-binding assays revealed that E.coli-derived non-glycoRBD had binding activity consistent with glycoRBD. The RBD was formulated with CpG ODN and Al(OH)₃ ad2022-01-01T00:00:00Z2022 Jul2025-04-04T10:02:23.596Z2025-04-04T10:02:23.596ZS-EPMC90759783553374710.1016/j.jim.2022.113279