Brucella lipopolysaccharide (LPS), a non-classical endotoxin and outer membrane component, plays an important role in host-Brucella interactions. The survival of Brucella inside the macrophages is critical for Brucella pathogenesis. The differential effects of smooth and rough B. abortus LPSs on bovine macrophages, neutrophils and murine macrophages were studied and compared. B. abortus LPSs were isolated from rough (RB51) and smooth (2308) strains and were purified. Both rough and smooth LPSs were used separately and in combination to activate bovine macrophages, neutrophils and murine...