## 1 Introduction  
Tuberculosis (TB) has been officially recognized as a global emergency since 1993 [1; 2] and is caused by airborne intracellular bacilli of the _Mycobacterium tuberculosis_ (Mtb) complex [3]. According to the Global Tuberculosis Report 2019, TB remains one of the top ten causes of death worldwide [4] and is the leading cause of death associated with an infectious disease in adults [1], particularly in low-income countries [2]. Every day, nearly 4000 people die due to TB [4; 5], and part of this high number is due the lack of effective vaccines and diagnostic tools [6; 7]. The bacillus Calmette-Guerin (BCG) of _Mycobacterium bovis_ is currently the only vaccine available worldwide for the prevention of tuberculosis, with a protective efficacy of up to 80% against severe forms of TB (i.e., miliary and meningeal) [8; 9]. However, against pulmonary TB, the most common form of the disease, this vaccine is only 50-80% effective [10]. These variations in the protective efficacy have inspired efforts to develop new vaccines, including subunit vaccines [11; 12; 13], live vaccines against bacteria within the same complex [14] and recombinant vaccines consisting of immunogenic antigens [15; 16]. So far,none of these vaccines has successfully elicited a better immune response than the BCG vaccine [17; 18]. Other attempts to achieve better results than the BCG vaccine have been investigated, in particular live bacterial vaccines, with _Mycobacterium vaccae_ or _Mycobacterium microti_, which belong to the _Mycobacterium tuberculosis_ complex (MTBC) [19; 20]. _M. microti_ causes pulmonary TB in voles but is naturally attenuated in humans [19]. Between 1950 and 1969, this strain was used as a TB vaccine, and showed approximately a 77% protective efficacy with the same immunogenicity against TB [21]. However, about 3-17% of patients that were vaccinated with _M. microti_ developed skin reactions with a more lupoid aspect and a greater severity than those vaccinated with BCG, which led to discontinuation of the _M. microti_ vaccine [22]. This effect was attributed to the administration of the _M. microti_ vaccine with multiple clicks. _M. microti_ has been used as a vaccine in animal models and for alternative routes of administration, such as intraperitoneal, orogastric and intravenous administration. These studies demonstrated that _M. microti_ conferred similar protection levels as the post-infection BCG vaccine when tested against the _M. tuberculosis_ strain CDC1551 in mice [19; 23]. The increase in multi-drug resistance of Mtb compared to classical treatments such as rifampicin and isoniazid [24; 25], estimated to cost USD 13 billion annually worldwide [4], has made the development of more effective vaccines and diagnostics more urgent. In this sense, the research into Mtb virulence factors such as immunogenic antigens are attractive, as they have shown promising results when used for these purposes [18]. Mtb produces several antigenic proteins, some of which are post-translationally modified, notably by mannose type glycan attachments [26; 27; 28; 29] which contribute to disease persistence by allowing bacteria to colonize and invade the host cell [28; 30; 31; 32]. These secreted Mtb proteins, including PstS-1 and Ag85B, trigger antigen-specific host immune responses [33]. [PERSON] et al., postulated that the PPE1 protein participates in the uptake of disaccharides from _M. tuberculosis_[34]. PstS-1 (Rv0934) is a 38 kDa cell wall glycol lipoprotein with attached mannoses. This antigen has been described as an adhesion that induces the proliferation of CD4+ T cells and induces the expression of high levels of interferon (IFN)-\(\gamma\) and immunoglobulin (Ig)G2a [35]. In addition, PstS-1 induces the upregulated production of interleukin (IL)-12 by macrophages and stimulates the CD8+ cytotoxic T-cells [36; 37; 38; 39]. Ag85B (Rv1886c) is a 30 kDa mycoll transferase that plays a role in the synthesis of the cell wall components. It is one of the main components of the culture filtrates in both the _M.