Emine Yesilyurt

Effects of Saccharomyces boulardii on cytokine secretion from intraepithelial lymphocytes infected by Escherichia coli and Candida albicans

Saccharomyces boulardii (S. boulardii) is a probiotic and used in the prevention or treatment of diarrhoea. Saccharomyces boulardii has many mechanisms to protect the host against diarrhoeal pathogens. It might modulate the immune system. In this study, the influence of S. boulardii on the secretion of cytokines from intraepithelial lymphocytes (IELs) infected with Escherichia coli (E. coli) and Candida albicans (C. albicans) was investigated in vitro. Cytokine levels were determined by enzyme‐linked immunosorbent assay. The secretion of proinflammatory cytokines such as interleukin (IL)‐1β was decreased in the infected IELs incubated with S. boulardii, but different from it, anti‐inflammatory cytokine levels such as IL‐4 and IL‐10, however, were found to be higher. These findings demonstrated that S. boulardii may have protective effects against diarrhoeal pathogens by reducing the proinflammatory response.

Immunomodulatory Effects of Voriconazole and Caspofungin on Human Peripheral Blood Mononuclear Cells Stimulated by Candida albicans and Candida krusei

Background:Candida infections are frequently associated with high morbidity and mortality rates in immunosuppressed patients. T cell–mediated and phagocytic immunity are the primary protective immune responses against fungal infections. Antifungal agents such as voriconazole and caspofungin enter phagocytic cells and lead to various intracellular activities. In this study, the authors aimed to investigate the immunomodulatory effects of voriconazole and caspofungin on human peripheral blood mononuclear cells (PBMC) stimulated by Candida albicans and Candida krusei. Methods:Human PBMC isolation was performed by Ficoll-hypaque density-gradient centrifugation method. Cell proliferation was assessed by colorimetric method using MTT. The cytokine levels in the human PBMC culture supernatants stimulated by C. albicans and C. krusei were determined by enzyme-linked immunosorbent assay. Results:The addition of voriconazole and caspofungin lead to proliferation of PBMC. In the presence of voriconazole and caspofungin, the levels of IL-2, IFN-&ggr; and IL-6 remarkably increased in PBMC stimulated by C. albicans and C. krusei. However, the combination of antifungal drugs and PBMC stimulated by Candida species did not increase the levels of TGF-&bgr; and IL-10. Conclusions:The results indicate that voriconazole and caspofungin have immunomodulatory effects on human PBMC stimulated by Candida species. The interaction between antifungal drugs and PBMC stimulates Th1-type cytokine secretion. Cytokine stimulation from immune cells can assist in the elimination of fungal pathogens. Therefore, during the treatment of fungal infection, putative immunomodulatory effects of antifungal agents should be taken into account.

Cytokine profile in murine toxoplasmosis.

OBJECTIVE To investigate which cytokines are produced after acute infection of mice with Toxoplasma gondii (T. Gondii) RH strain. METHODS Mus domesticus domesticus mice in infected group were inoculated with with highly virulent T. Gondii RH strain by intraperitoneally. Serum samples were obtained from infected and non-infected mice for cytokine levels for ELISA assay. RESULTS The concentrations of tumor necrosis factor-α, interferon-γ, interleukin (IL)-10 and IL-12 in the cardiac blood sample of the infected mice were significantly higher than those in uninfected controls (P<0.05). The levels of transforming growth factor-1β decreased in mice infected with T. gondii compared to those of the controls, the decrease was statistically significant (P<0.05). No significant difference was observed in levels of IL-4 between infected and healty control groups (P>0.05). CONCLUSIONS According to our findings, immune response into T helper type 1 was predominant during acute T. gondii infection. Further characterization and purification of Toxoplasma molecule(s) implicated in the regulation of cytokines could lead to the development of new drug prospects to control Toxoplasma infection.

The Efficiency of Viscum album ssp. album and Hypericum perforatum on Human Immune Cells In Vitro

Viscum album L. ssp. album and Hypericum perforatum L. are used for the treatment of different diseases. In this study, the effects of these herbals on immune cells were assessed in vitro. The phagocytosis, candidacidal activity of neutrophils and adhesion function of epithelial cells were investigated. Also, the expression of the surface markers of lymphocytes was analyzed by flow cytometry. It was observed that V. album ssp. album increased phagocytic activity and candidacidal activity of neutrophils and decreased adhesion function of epithelial cells. We also observed that in human peripheral blood mononuclear cells stimulated by Viscum album L. ssp. album the levels of CD4+CD25+ and CD8+CD25+ T cells, CD69 expressions in the activated T lymphocytes and CD3-CD16+CD56+ NK cells increased compared to the cells that were not stimulated by this herbal. Whereas CD4+CD25+, CD8+CD25+ T cells, CD 69 expression and CD3-CD16+CD56+ Natural killer cells did not show any significant differences with the presence of Hypericum perforatum L. compared to the control group. Hypericum perforatum L. increased candidacidal activity of neutrophils and decreased adhesion function of epithelial cells. In the light of these findings, it is considered that these extracts may be used as an adjuvant treatment option for immune activation in immunosuppressed patients.

Cytokine levels in patients with Epstein―Barr virus associated laryngeal carcinoma

OBJECTIVE Some researchers have suggested that Epstein-Barr virus may play a role in the pathogenesis of laryngeal malignancies. In order to clarify the role of cytokines in this disease context, the current study aimed to determine the serum levels of cytokines in Epstein-Barr virus DNA positive patients with laryngeal carcinoma. SUBJECTS The study included 10 patients with diagnosed laryngeal carcinoma and Epstein-Barr virus DNA positive tumour tissue samples. The control group comprised 10 Epstein-Barr virus DNA negative patients diagnosed with laryngeal carcinoma, 10 patients with acute Epstein-Barr virus infection and 10 healthy individuals. METHOD Serum cytokine levels were determined by enzyme-linked immunosorbent assay. RESULTS The Epstein-Barr virus DNA positive and negative laryngeal carcinoma patients showed no differences regarding serum levels of the following cytokines: interleukins 1beta, 2, 6 and 12, tumour necrosis factor alpha, and interferon gamma. However, serum levels of interleukin 10 and transforming growth factor beta1 were significantly higher in Epstein-Barr virus DNA positive laryngeal carcinoma patients compared with Epstein-Barr virus DNA negative laryngeal carcinoma patients (p < 0.05). CONCLUSION Our results suggest that the cytokines interleukin 10 and transforming growth factor beta1 may act as growth factors in Epstein-Barr virus related laryngeal carcinoma. These cytokines may thus represent potential targets for molecular therapeutic treatment for laryngeal carcinoma; they may also be useful as indicators of disease prognosis.