Serine protease PepA (Rv0125) (PepA)

Rv0125, also known as PepA or Mtb32A, is a 32-kDa secreted serine protease from Mycobacterium tuberculosis that serves as a major immunodominant antigen [1, 3]. It is highly conserved across various strains of the M. tuberculosis complex and is recognized by the immune systems of individuals with both latent and active tuberculosis infections [2, 4]. Biologically, the protein functions as a protease, likely involved in the degradation of host or bacterial proteins to support pathogen survival [1]. In clinical development, Rv0125 is a key component of the M72/AS01E recombinant protein vaccine candidate, where it is fused with the Rv1196 antigen to elicit a protective immune response [2]. The primary mechanism of action involves the induction of a robust Th1-type cytokine response, specifically the activation of CD4+ T cells that produce interferon-gamma (IFN-gamma) [2, 4]. This targeted immune activation is designed to prevent the progression of latent tuberculosis to active pulmonary disease [2]. Clinical trials have demonstrated that targeting this antigen can significantly reduce the incidence of tuberculosis in high-risk populations [2, 4]. Beyond its role in vaccines, Rv0125 is also investigated for its potential as a diagnostic biomarker due to its high specificity to the M. tuberculosis complex [1, 3]. Sources: [1] UniProt P9WGI1; [2] Van Der Meeren et al. (2018) NEJM; [3] Skeiky et al. (1999) Infect Immun; [4] Tait et al. (2019) NEJM.

Other names

Mtb32ARv012532 kDa antigenHsp32Serine protease PepA

Induction of antigen-specific Th1-mediated immune response, primarily through CD4+ T-cell activation and interferon-gamma production.