Endogenous gamma interferon mediates resistance to Brucella abortus infection

Abstract

Depletion of endogenous gamma interferon (IFN-y) with anti-IFN-y monoclonal antibody resulted in increased numbers of BruceUla abortus in the spleen and liver of infected CBA mice. This increase was accompanied by a decrease in splenomegaly and a lower proportion of macrophages in the spleen. Furthermore, treatment of recipient mice with anti-FN-y antibody blocked the adoptive transfer of resistance with immune T cells. Together, the results indicated that endogenous IFN-y plays an important role in mediating resistance to primary and secondary BruceUla infection.

Defective interferon‐gamma production by T‐lymphocytes from patients with acute brucellosis

“…In animal models of Brucella infection, it has been shown that IFNactivated macrophages show increased anti-brucellae effects [19]. Furthermore, it has been reported that endogenous IFNplays an important role in mediating resistance to Brucella infection in mice [11]. Our finds may thus indicate the existence of impaired macrophage activation in patients with acute untreated brucellosis associated with the defective production of IFNby T-lymphocytes.…”

“…Impaired macrophage function allows the survival of Brucella in the cytoplasm of these phagocytic cells. In animal models of Brucella infection, it has been shown that an inadequate macrophage response appears to be involved in the deficient clearance of the Brucellae found in the acute infection [10,11]. In humans, we have found that deficient IFNproduction by T-lymphocytes is associated with the active acute infection.…”

“…Several changes in the immune system have been described in association with acute brucellosis in experimental models. The immunodeficiency found in these animal models appears to be involved in the pathogenesis of the Brucella infection [10][11][12][13]. It is possible to suggest that an abnormal protective immune response to brucella might be observed during the course of the human infection.…”

Anaplasma marginale: effect of the treatment of cattle with an interferon γ‐neutralizing monoclonal antibody or the nitric oxide synthetase inhibitor aminoguanidine on the course of infection

“…Interferon gamma (IFN-g) is a cytokine with pleiotropic effects, produced by helper T-lymphocytes involved in CMI responses against a wide variety of pathogens, including intracellular bacteria (Kiderlen et al 1984, Gould & Sonnenfeld 1987, Zhan & Cheers 1993 and rickettsia (Li et al 1987). Production of high levels of IFN-g in-vitro has been demonstrated during lymphocyte proliferative responses against A. marginale (Gale et al 1996).…”

Use ofS-[2,3-Bispalmitoyiloxy-(2R)-Propyl]-R-Cysteinyl-Amido-Monomethoxy Polyethylene Glycol as an Adjuvant Improved Protective Immunity Associated with a DNA Vaccine Encoding Cu,Zn Superoxide Dismutase of Brucella abortus in Mice

“…In the infected host, B. abortus multiplies within the phagosomes of reticuloendothelial cells, avoiding the killing effect of the macrophages by inhibiting phagosome-lysosome fusion (4). Like other facultative intracellular bacterial pathogens, resistance to B. abortus depends on acquired cell-mediated immunity (CMI) (5). The Th1 subset of CD4 ϩ lymphocytes that secrete gamma interferon (IFN-␥), which upregulates macrophage anti-Brucella activity, seems to present a critical bacterial clearance mechanism (6,7).…”