Development of chimeric potyvirus like particles carrying tuberculosis antigens

Abstract

Tuberculosis (TB) remains a significant focus in vaccine research due to newlineBCG inadequacies, the complexity of disease interventions, ambiguities in newlinedisease diagnosis, and the emergence of multi-drug-resistant TB strains. Subunit newlinevaccines are advantageous over other vaccination strategies and entail newlineappropriate adjuvants as most potential Mycobacterium tuberculosis (Mtb) newlineantigenic proteins are of low molecular weight. Adjuvants capable of eliciting newlinehumoral and cell-mediated immune responses are essential for successful TB newlinevaccine development. CFP10 and ESAT6, the mycobacterial vaccine candidates, newlinerequire suitable adjuvants to enhance the immune response. Virus-like particles newline(VLPs), presenting repetitive copies of foreign antigens, can stimulate T and B newlinecell-mediated immunity, essential for protection against intracellular pathogens. newlineIn this study, we developed chimeric potyvirus-like particles (PVLPs) displaying newlinemycobacterial antigens on their surface by translationally fusing the coat protein newline(CP) gene from the Johnsongrass mosaic virus with CFP10 and/or ESAT6 genes. newlineRecombinant plasmids carrying these fusion constructs were transformed into E. newlinecoli, and the fusion proteins (ESAT6-CP, CP-CFP10, and ESAT6-CP-CFP10) newlinewere expressed and purified using Ni-NTA2+ affinity chromatography under newlinedenaturing conditions. These chimeric CP fusion proteins were then selfassembled newlineinto PVLPs in vitro by gradually removing the denaturing conditions. newlineWhen the purified hybrid PVLPs carrying Mtb antigens were injected into mice, newlinehigher antigen-specific antibody titer was observed compared to the same newlineantigens without an adjuvant. In vitro stimulation of splenocytes from newlineimmunized mice upregulated the expression of cytokines involved in the TB newlineimmune response. Chimeric PVLPs displaying Mtb antigens also showed newlineincreased lymphocyte proliferation. The outcome of the present investigation newlinereveals that JGMV PVLPs carrying Mtb antigens could be pursued further as a newlinepotential vaccine candidate. newline