CD8A and brucellosis: As a result, these factors or those associated with them (i.e., secretion system) can potentially be processed and presented in MHC I molecules via the endogenous pathway (Figure 3), in alternate presentation pathways to CD8+ T cells, a T cell subset important for protection against brucellosis (Oliveira and Splitter, 1995; Blanchard and Shastri, 2010; Grillo et al., 2012).