creators_name: Vij, Shania
creators_name: Thakur, Reena
creators_name: Singh, Raghwendra Pratap
creators_name: Kumar, Rashmi
creators_name: Pathania, Preeti
creators_name: Gupta, Varsha
creators_name: Suri, Chander Raman
creators_name: Rishi, Praveen
type: article
datestamp: 2026-03-27 09:22:27
lastmod: 2026-03-27 09:22:27
metadata_visibility: show
title: Dual immunization with CdtB protein and flagellin epitope offers augmented protection against enteric fever in mice
ispublished: pub
subjects: QR
keywords: CdtB protein; Dual immunization; Enteric fever; Flagellin epitope; Salmonella Paratyphi; Salmonella Typhi; Vaccine
note: Copyright of this article belongs to Elsevier BV
abstract: AIMS: Present study has explored the protective response of dual immunization using two different antigenic entities (i.e. flagellin epitope and cytolethal distending toxin subunit B (CdtB) protein) against lethal challenge of typhoidal serovars in a murine model. MAIN METHODS: In-vitro immunogenicity of flagellin epitope-BSA conjugate and CdtB protein was confirmed using Indirect ELISA of typhoid positive patients' sera. Further, both entities were administered intraperitoneally in mice individually or in combination, followed by lethal challenge of typhoidal Salmonellae. Various parameters were analysed such as bacterial burden, mice survival, histopathological analysis, cytokine analysis and immunophenotyping. Serum samples obtained from the immunized mice were used for passive immunization studies, wherein mice survival and mechanism of action of the generated antibodies was studied. KEY FINDINGS: Active immunization studies using the combination of both entities demonstrated improved mice survival after lethal challenge with typhoidal Salmonellae, reduced bacterial burden in organs, expression of immunophenotypic markers in splenocytes and restored tissue histoarchitecture. When used in combination, the effective doses of both the candidates reduced which may be attributed to multiprong approach used by the immune system to recognize Salmonella. Passive immunization studies further determined the protective efficacy of generated antibodies by different mechanisms such as complement mediated bactericidal action, swarming inhibition and increased phagocytic uptake. SIGNIFICANCE: Present study is the first phase of the proof-of-concept which may prove to be beneficial in developing an effective bi-functional vaccine candidate to render protection against both Vi-positive as well as Vi-negative Salmonella strains.
date: 2023-12-01
date_type: published
publication: Life Sci.
volume: 334
number: 122216
publisher: Elsevier BV
pagerange: 122216
refereed: TRUE
official_url: https://www.sciencedirect.com/science/article/pii/S0024320523008512?via%3Dihub
citation:   Vij, Shania and Thakur, Reena and Singh, Raghwendra Pratap and Kumar, Rashmi and Pathania, Preeti and Gupta, Varsha and Suri, Chander Raman and Rishi, Praveen  (2023) Dual immunization with CdtB protein and flagellin epitope offers augmented protection against enteric fever in mice.  Life Sci., 334 (122216).  p. 122216.