Immunogenicity of recombinant Mycobacterium bovis bacille Calmette–Guèrin clones expressing T and B cell epitopes of Mycobacterium tuberculosis antigens

Rohimah Mohamud,Maryam Azlan,Daniel Yero,Nadine Alvarez,Mohd-Nor Norazmi,Armando Acosta,Maria E Sarmiento

doi:10.1186/1471-2172-14-s1-s5

Rohimah Mohamud, Maryam Azlan + Show 5 more

Open Access

https://doi.org/10.1186/1471-2172-14-s1-s5

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Journal: BMC immunology	Publication Date: Feb 1, 2013
Citations: 37	License type: cc-by

Affiliation: Universiti Sains Malaysia, Finlay Institute

Abstract

Recombinant Mycobacterium bovis bacille Calmette–Guèrin (rBCG) expressing three T cell epitopes of Mycobacterium tuberculosis (MTB) Ag85B antigen (P1, P2, P3) fused to the Mtb8.4 protein (rBCG018) or a combination of these antigens fused to B cell epitopes from ESAT-6, CFP-10 and MTP40 proteins (rBCG032) were used to immunize Balb/c mice. Total IgG responses were determined against Mtb8.4 antigen and ESAT-6 and CFP-10 B cell epitopes after immunization with rBCG032. Mice immunized with rBCG032 showed a significant increase in IgG1 and IgG2a antibodies against ESAT-6 and MTP40 (P1) B cell epitopes and IgG3 against both P1 and P2 B cell epitopes of MPT40. Splenocytes from mice immunized with rBCG018 proliferated against Ag85B P2 and P3 T cell epitopes and Mtb8.4 protein whereas those from mice-immunized with rBCG032 responded against all Ag85B epitopes and the ESAT-6 B cell epitope. CD4+ and CD8+ lymphocytes from mice immunized with rBCG018 produced primarily Th1 type cytokines in response to the T cell epitopes. Similar pattern of recognition against the T cell epitopes were obtained with rBCG032 with the additional recognition of ESAT-6, CFP-10 and one of the MTP40 B cell epitopes with the same pattern of cytokines. This study demonstrates that rBCG constructs expressing either T or T and B cell epitopes of MTB induced appropriate immunogenicity against MTB.

Highlights

Tuberculosis (TB) is one of the most prevalent diseases in developing countries
The immunogenicity of the Recombinant Mycobacterium bovis bacille Calmette–Guèrin (rBCG) expressing three T cell epitopes of the Ag85B antigen of Mycobacterium tuberculosis (MTB) fused to the entire sequence of MTB8.4 protein and the same construct fused to B cell epitopes of ESAT-6, CFP-10 and MTP-40 proteins of MTB were evaluated to determine its ability to induce specific humoral and cellular immune responses against these epitopes
Analysis of intracellular cytokines 10 μg/ml of each peptide corresponding to the T and B cell epitopes or recombinant Mtb8.4 protein were cultured with 2 × 106 spleen cells/ml

Summary

Introduction

Tuberculosis (TB) is one of the most prevalent diseases in developing countries. WHO estimates that 8.7 million new cases and approximately 1.6 million deaths occur annually [1,2]. * Correspondence: norazmi@kb.usm.my 1School of Health Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia Full list of author information is available at the end of the article T and B cell epitopes of MTB were cloned into BCG.

Results

Conclusion