Publication date: Jun 24, 2025
Viral-bacterial co-infections pose significant global health challenges. Currently, there are limited vaccines that target both viral and bacterial pathogens simultaneously. In this study, we present HRBD, a novel fusion protein vaccine combining the receptor-binding domain (RBD) of SARS-CoV-2 and a detoxified α-hemolysin mutant (Hla) from S. aureus. When tested in mice, HRBD induced robust IgG1-dominated antibody responses against both antigens, leading to neutralizing effects against SARS-CoV-2 pseudovirus (NT ∼ 10) and S. aureus hemolytic activity (NT ∼ 10). HRBD promoted a Th2 immune response with increased IL-4 levels, while also boosting IFN-γ production. Importantly, HRBD showed dose-sparing efficacy, achieving similar immune responses as high-dose single or mixed-antigen vaccines with half the antigen amount. Functional tests confirmed that HRBD sera could neutralize Hla-induced cell lysis and block SARS-CoV-2 entry and syncytium formation. HRBD vaccination protected hACE2 transgenic mice against the co-infection of SARS-CoV-2 pseudovirus and S. aureus. These results suggest that HRBD is a promising candidate for preventing SARS-CoV-2 and S. aureus co-infections.
| Concepts | Keywords |
|---|---|
| Mice | Bivalent vaccine |
| Mutant | Fusion protein |
| Nt10 | RBD |
| Sparing | Viral-bacterial co-infection |
| Vaccines | α-Hemolysin |
Semantics
| Type | Source | Name |
|---|---|---|
| disease | IDO | protein |
| disease | MESH | co-infections |
| drug | DRUGBANK | Binetrakin |
| disease | IDO | production |
| disease | IDO | cell |