Recombinant Proteins as Antigens in Serological Diagnosis of Brucellosis

Brucellosis is considered the major zoonosis in developing countries. In susceptible ani‐ mal species, diagnosis of brucellosis remains a challenge due to the variety of clinical signs that it shares with a wide range of diseases. At present, isolation of Brucella is con‐ sidered the gold standard for diagnosis of brucellosis; because of its low sensitivity and be‐ coming potentially hazardous to laboratory technicians, serology is used for the detection of specific antibodies induced by infection. However, since traditional methods common‐ ly show drawbacks and do not differentiate between vaccinated and naturally infected animals, it is necessary to search and test immunoreactive molecules for specific diagno‐ sis of Brucella-infected cattle, thus significantly reducing the killing of suspected herds mainly due to vaccination. Advances in biotechnology have allowed exploring the use of recombinant proteins as antigens to avoid the risk involved in the use of viable Brucella strains. The benefit of using recombinant proteins, such as outer membrane proteins (OMP) and other non-lipopolysaccharide (non-LPS) molecules as antigens, for serological diagnosis is promising, but there are still many concerns about their application. The aim of the present work is to show advances in the use of recombinant antigens and discuss their advantages and potential use as markers for the serological diagnosis in brucellosis.