CD40LG and brucellosis: Generally, because of the variability in the specificity and sensitivity of the conventional serological tests routinely used in high-risk regions, a combination of varying serological tests (e.g. SAT and either indirect Coombs, Brucellacapt, or ELISA for IgG and IgM) is recommended for the definitive diagnosis of human brucellosis [97,98,100–102].