In vivo, IL-6, TNF-α, and CD80/CD86 are required in the activation of the interferon gamma-producing T CD4+ helper type 1 (Th1) and T CD8+ cytotoxic, a protective response induced by the host against brucellosis (Vitry et al., 2012; Skendros and Boura, 2013; Dorneles et al., 2015; Ahmed et al., 2016). This evidence concerns the gene CD8A and brucellosis.