African Journal of Agriculture

Full Length Research Paper

Synthetic Gene Expression of Mycobacterium Tuberculosis Epitopes on Salmonella Typhi Ty21a Using pgsA Anchor Protein

Badrul S. M. Zainuddin¹*, Mustaffa Musa² and Zainul F. Zainuddin³

¹Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.

²School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian Kelantan, Malaysia.

³School of Health Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.

Accepted 28 October, 2023

Abstract

We have developed a recombinant Salmonella typhi Ty21a vaccine candidate (rSTvacIII) displaying a multi-epitopes mycobacterial antigen called the VacIII (containing ubiquitin and 4 immunogenic mycobacterial epitopes of ESAT-6, PhoS1, Hsp 16.3 and MTB 8.4 genes) on the surface of S. typhi Ty21a (Ty21a) using PgsA protein as a carrier. The expression of VacIII protein on the surface of Ty21a was verified by western blot. Immunization in BALB/c mice with rSTvacIII induced strong Th1-type responses based on high level of in vitro IFN- but low IL-4 secretion. Since the protective immunity against tuberculosis is mediated by Th1-type response, the rSTvacIII have potential as effective vaccine candidate against tuberculosis.

Key words: VacIII antigen, PgsA anchoring motif, tuberculosis, Salmonella typhi Ty21a.