Typhoid toxin is secreted by the typhoid fever-causing bacterial pathogen Salmonella enterica serovar Typhi and has tropism for immune cells and brain endothelial cells. Here, we generated a camelid single-domain antibody (VHH) library from typhoid toxoid-immunized alpacas and identified 41 VHHs selected on the glycan receptor-binding PltB and nuclease CdtB. VHHs exhibiting potent neutralizing activities from each sequence-based family were epitope binned via competition enzyme-linked immunosorbent assays (ELISAs), leading to 6 distinct VHHs, 2 anti-PltBs (T2E7 and T2G9), and 4 anti-CdtB VHHs (T4C4, T4C12, T4E5, and T4E8), whose neutralizing activities and associated toxin-neutralizing mechanisms were investigated. We found that T2E7, T2G9, and T4E5 effectively neutralized typhoid toxin , as demonstrated by 100% survival of mice administered a lethal dose of typhoid toxin and with little to no typhoid toxin-mediated upper motor function defect. Cumulatively, these results highlight the potential of the compact antibodies to neutralize typhoid toxin by targeting the glycan-binding and/or nuclease subunits.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8852740 | PMC |
http://dx.doi.org/10.1128/IAI.00515-21 | DOI Listing |
Vet Res
January 2025
College of Veterinary Medicine, Jeonbuk National University, Iksan Campus, Iksan, 54596, Republic of Korea.
Fowl typhoid (FT) poses a significant threat to the poultry industry and can cause substantial economic losses, especially in developing regions. Caused by Salmonella Gallinarum (SG), vaccination can prevent FT. However, existing vaccines, like the SG9R strain, have limitations, including residual virulence and potential reversion of pathogenicity.
View Article and Find Full Text PDFPLoS Negl Trop Dis
November 2024
Department of Medical Microbiology, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
Gut Microbes
November 2024
College of Veterinary Medicine, Southwest University, Beibei, Chongqing, China.
Non-typhoidal (NTS) is a major global foodborne pathogen that poses a major public health concern worldwide, and no vaccines are available for protecting against infection of multiple serotypes, therefore, the development of vaccines to provide broad protection is valuable. In this work, we aimed to regulate lipopolysaccharide (LPS) synthesis of live for exposing conserved protein antigens on the outer membrane while maintaining smooth LPS patterns to keep their original ability to invade host cells for inducing cross-protection against infection of multiple serotypes. We generated a series of mutants defective in genes to affect the length of LPS.
View Article and Find Full Text PDFSci Rep
November 2024
Laboratorio de Referencia Nacional de Bacteriología Clínica, Instituto Nacional de Salud, Lima, Peru.
Nat Commun
October 2024
Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
Systemic vaccination of macaques with V1-deleted (ΔV1) envelope immunogens reduce the risk of SIV acquisition by approximately 60%, with protective roles played by V2-specific ADCC and envelope-specific mucosal IL-17NKp44 innate lymphoid cells (ILCs). We investigated whether increased mucosal responses to V2 benefit vaccine efficacy by delivering oral nanoparticles (NPs) that release V2-scaffolded on Typhoid Toxin B (TTB) to the large intestine. Strikingly, mucosal immunization of male macaques abrogated vaccine efficacy with control TTB or empty NPs, but vaccine efficacy of up to 47.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!