HspX vaccination and role in virulence in the guinea pig model of tuberculosis

In this report, three HspX formulas (native and two recombinant variants) were used as vaccines in the guinea pig model of tuberculosis; none were protective during challenge with WT Mtb. However, recombinant HspX was protective in animals challenged with a strain of Mtb lacking hspX (X4‐19), indicating protection was driven by molecules co‐purifying with HspX or an adjuvant effect of recombinant HspX in this system. Mtb X4‐19 was significantly less virulent than WT Mtb. Quantitative PCR and whole genome sequencing identified several genes (Rv2030c‐Rv2032, Rv1062, Rv1771, Rv1907, and Rv3479) with altered expression that may contribute to loss of virulence. Physiological differences required for the establishment of Mtb infection in different hosts may affect the potential of subunit vaccines to elicit protection, supporting the need for rigorous biochemical and modeling analyses when developing tuberculosis vaccines. HspX, a protein induced during chronic Mycobacterium tuberculosis infection, is studied as a vaccine candidate and virulence determinant in a relevant model of tuberculosis.
Source: FEMS Immunology and Medical Microbiology - Category: Microbiology Authors: Tags: Research Article Source Type: research