Potential use of Rv2626c antigen for developing vaccines against latent tuberculosis

AMIANO N.O.; TATEOSIAN N.L.; LIZARRAGA F.; ERSCHEN A.; PALMERO D.J.; GHERARDI MM.; MORELLI M.P.; PELLEGRINI, J.M.; TOLEDO F.; STUPKA J.; GALLEGO C.; CALAMANTE G.; CASTELLO F.A.; NAGUILA Z.; CUSMANO L.; ARMITANO R; DEL MEDICO ZAJAC, MP.; GARCÍA, V.E.

Mar del Plata

Congreso; LXVI Reunion Anual de la Sociedad Argentina de Inmunologia (SAI); 2018

Sociedad Argentina de Inmunología

Mycobacterium tuberculosis (Mtb) causes nearly 10 million of new cases of tuberculosis (TB) and 1.5 million of deaths per year. This global epidemic has been favored by the absence of an effective vaccine, the emergency of multi-resistant strains and the lack of sensitive and fast diagnostic methods. At present, the only vaccine approved to be used in humans is M. bovis-BCG, which poorly protects adults but is effective in children up to 5-6 years old. An estimated one third of the world population is latently infected with Mtb (LTBI) and at risk of disease reactivation. The existence of such a huge reservoir of the bacteria denotes the need of a rapid diagnosis of TB infection for its early detection and control. Approximately 10% of people with LTBI will develop active TB disease during their lifetime, the majority within the first five years after initial infection. This risk of reactivation is higher in immune-compromised persons, such as in people who are infected with HIV and in persons suffering from other conditions that impair the immune system. Ag85A is one of a family of three secreted and membrane retained enzyme isoforms, highly conserved across mycobacteria and involved in the synthesis of important constituents for the cell wall. They are thought to promote bacterial survival in macrophages along with adhesion/invasion and dissemination in host cells. Ag85A is also an immunogenic Ag that is recognized by T cells and it is considered a potential candidate for boosting cellular immunity primed by BCG .