interleukin-8 and Brucellosis

Brucellae are intracellular bacterial pathogens that cause Brucellosis, bringing great economic burdens to developing countries. The pathogenic mechanisms of Brucella are still poorly understood. Earlier immune response plays an important role in the Brucella infection. Phosphoglyceromutase (PGM) and dihydrodipicolinate reductase (DapB) were cloned, expressed, purified, and their immunocompetence was analyzed. Cytokines were detected by murine macrophages (RAW 264.7) and splenocytes that stimulated with the two recombinant proteins. The immune responses were analyzed by ELISA from mice with the two recombinant proteins immunized. TNF-α, IL-6 and IL-8 were produced in stimulated RAW 264.7 cells and splenocytes. Th1-type cytokines, IFN-γ and IL-2, induced in RAW 264.7 cells and splenocytes were higher then Th2-type cytokines, IL-4 and IL-5. Th2-related immune response was induced in splenocytes obtained 35 days after mice immunized with the two proteins. The production of IgG1 was higher than IgG2a in immunized mice. Taken together, our results demonstrated that the two proteins could induce Th1 and Th2-type immune responses in vivo and in vitro.

Topics: Animals; Brucella abortus; Brucellosis; China; Cloning, Molecular; Cytokines; Dihydrodipicolinate Reductase; Female; Gene Expression Regulation, Bacterial; Genes, Bacterial; Immunization; Immunoglobulin G; Interferon-gamma; Interleukin-2; Interleukin-4; Interleukin-5; Interleukin-6; Interleukin-8; Macrophages; Mice; Mice, Inbred BALB C; Phosphoglycerate Mutase; RAW 264.7 Cells; Recombinant Proteins; Th1 Cells; Th2 Cells; Tumor Necrosis Factor-alpha

Trophoblasts are targets of infection by Brucella spp. but their role in the pathophysiology of pregnancy complications of brucellosis is unknown. Here we show that Brucella abortus invades and replicates in the human trophoblastic cell line Swan-71 and that the intracellular survival of the bacterium depends on a functional virB operon. The infection elicited significant increments of interleukin 8 (IL8), monocyte chemotactic protein 1 (MCP-1), and IL6 secretion, but levels of IL1beta and tumor necrosis factor-alpha (TNF-alpha) did not vary significantly. Such proinflammatory response was not modified by the absence of the Brucella TIR domain-containing proteins BtpA and BtpB. The stimulation of Swan-71 cells with conditioned medium (CM) from B. abortus-infected human monocytes (THP-1 cells) or macrophages induced a significant increase of IL8, MCP-1 and IL6 as compared to stimulation with CM from non-infected cells. Similar results were obtained when stimulation was performed with CM from infected neutrophils. Neutralization studies showed that IL1beta and/or TNF-alpha mediated the stimulating effects of CM from infected phagocytes. Reciprocally, stimulation of monocytes and neutrophils with CM from Brucella-infected trophoblasts increased IL8 and/or IL6 secretion. These results suggest that human trophoblasts may provide a local inflammatory environment during B. abortus infections either through a direct response to the pathogen or through interactions with monocytes/macrophages or neutrophils, potentially contributing to the pregnancy complications of brucellosis.

Topics: Brucella abortus; Brucellosis; Cell Line; Chemokine CCL2; Female; Humans; Inflammation; Interleukin-1beta; Interleukin-6; Interleukin-8; Macrophages; Monocytes; Phagocytes; Trophoblasts; Tumor Necrosis Factor-alpha

Increased levels of interleukin-8 (IL-8) and interleukin-6 (IL-6) in acute human brucellosis have been reported. Previous studies have shown that the production and level of IL-6 and IL-8 cytokines are associated with the polymorphism of the encoding genes.. To investigate the probable association between IL-6 (-174 C/G) and IL-8 (-251 A/T) gene polymorphisms and susceptibility/resistance to brucellosis.. The patient group included 196 patients suffering from Brucella infection and the control group consisted of 82 healthy animal husbandmen from the same geographical area. IL-8 (-251 A/C) and IL-6 (-174 C/G) gene polymorphisms were analyzed by PCR-RFLP and Allele Specific PCR (AS-PCR) respectively.. The frequency of -251 IL-8 AA genotype was significantly lower in the controls compared with that of the patients (p=0.0051), while the frequencies of other genotypes (AT and TT) and alleles (A and T) were not significantly different among the participants. No association was found between IL-6 (-174 C/G) polymorphism and brucellosis.. This study indicates that the IL-8 -251 AA genotype may be considered as a genetic susceptibility factor for brucellosis.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Brucella; Brucellosis; Child; Child, Preschool; DNA Mutational Analysis; Female; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Humans; Interleukin-6; Interleukin-8; Male; Middle Aged; Polymorphism, Genetic

Hepatic involvement is frequent in human brucellosis. While different histopathological lesions have been reported in these patients, the underlying cellular and molecular mechanisms have not been addressed.. This study assessed whether Brucella abortus can infect a human hepatoma cell line and induce a proinflammatory response in these cells.. The bacterium not only infected the human hepatoma cell line HepG2 but also exhibited intracellular replication. The infection induced hepatoma cells to secrete IL-8, and supernatants from Brucella-infected hepatoma cells were shown to induce the migration of human neutrophils. The infection also induced the expression of the intercellular adhesion molecule ICAM-1 on hepatoma cells, and the adhesion of neutrophils to these cells was significantly higher than to uninfected hepatoma cells. ICAM-1 expression was also induced by stimulation of hepatoma cells with supernatants from Brucella-infected neutrophils. While Brucella infection did not induce the expression of matrix metalloproteinases (MMPs) in hepatoma cells, it significantly induced MMP-9 in neutrophils. Hepatoma cell apoptosis was significantly induced by B. abortus infection and also by stimulation with supernatants from Brucella-infected neutrophils.. The present study provides clues regarding potential mechanisms of tissue damage during liver brucellosis.

Topics: Apoptosis; Brucella abortus; Brucellosis; Cell Adhesion; Cell Line, Tumor; Cell Movement; Culture Media, Conditioned; Hepatocytes; Humans; Intercellular Adhesion Molecule-1; Interleukin-8; Liver Diseases; Matrix Metalloproteinase 9; Neutrophils

The authors report the clinical course and immune system response of a patient with disease-associated recurrent transverse myelitis (TM) following cerebral infection with Brucellosis melitensis. The patient suffered four recurrences of his TM (each at a distinct spinal cord level) over the course of 2 years following his initial presentation, which ultimately progressed to quadriplegia. He had progressively declining cerebrospinal fluid (CSF) brucella antibody titers, suggesting a postinfectious, rather than an infectious, etiology. The authors simultaneously examined the expression of multiple cytokines in the CSF of this patient using cytokine antibody arrays and found a marked elevation of interleukin (IL)-6, IL-8, and macrophage chemoattractant protein (MCP)-1 levels relative to controls. Quantitative enzyme-linked immunosorbent assay (ELISA) analysis of the CSF confirmed a 1700-fold elevation of IL-6 and more modest elevations of IL-8 and MCP-1. IL-6 levels returned to baseline following treatment of the patient with intravenous cyclophosphamide and plasma exchange and the patient experienced a significant and sustained recovery of function.

Topics: Aged; Brucellosis; Chemokine CCL2; Cyclophosphamide; Humans; Immunosuppressive Agents; Injections, Intravenous; Interleukin-6; Interleukin-8; Male; Myelitis, Transverse; Recurrence; Spinal Cord; Treatment Outcome