Systems Biology and Bioinformatics Help Decipher Brucella Antigens Involved in Clinical Manifestation of the Disease

Cannella et al. (2012) published an article in this issue that aims at identifying serum antibodies associated with clinical manifestation of human brucellosis. They hypothesized that these antibodies can predict potential Brucella antigenic candidates, and may also have diagnostic, prognostic, and vaccine value. The authors also predicted that by elucidating the antibody profiles of groups of people (including Brucella culture or Rose Bengal assay positive or negative patients, or a naïve population from Brucella-free regions), without knowing specific infection details, common Brucella antigens significant in the clinical manifestation of the disease would be revealed. Based on this hypothesis, many Brucella proteins, including the Type IV secretion system protein VirB8 (Table 1) and VirB5 (Table 3), Outer membrane lipoproteins Omp10, Omp16, and Omp19 (Table 1), and iron metabolism protein Bacterioferritin, were identified to generate antigen-specific antibody immune responses and could be used as potential diagnosis markers or vaccine targets. This approach assumes that the immune system would respond by a similar antibody repertoire in correlation with a manifested clinical situation. Using a proteome microarray expressing nearly all B. melitensis genes, such a systems biology method systematically analyzes Brucella antibody profiles of human sera in response to physiological and environmental cues. A commentary on