Bacillus Calmette-Guerin (BCG) is reported to suppress Th2 response and asthmatic reaction. Dendritic cells (DCs), the major antigen-presenting cells, infections with BCG are known to result in inducing various cytokines. Thus, DCs are likely to play a role in the effects of BCG on asthma. This study aims at investigating that cytokine milieu secreted by BCG-treated DCs directly enhances allergen-specific Th1 response and/or suppresses Th2 response in allergic asthma. DCs and CD3+ T cells were generated from Dermatophagoides farinae-sensitive asthmatics. DCs were cultured with and without BCG and subjected to flow cytometric analysis. IL-12 and IL-10 were determined from the culture supernatants. Some DCs were cocultured with T cells in the presence of D. farinae extracts after adding the culture supernatants from BCG-treated DCs, and IL-5 and IFN-gamma were determined. BCG-treated DCs enhanced significantly the expressions of CD80, CD86, and CD40, and the productions of IL-12 and IL-10. Addition of culture supernatants from BCG-treated DCs up-regulated production of IFN-gamma by T cells stimulated by DCs and D. farinae extracts (p<0.05), but did not down-regulate production of IL-5 (p>0.05). The cytokine milieu secreted by BCG-treated DCs directly enhanced allergen-specific Th1 response, although did not suppress Th2 response.
Antigens, Dermatophagoides/*immunology ; Asthma/*immunology ; Cells, Cultured ; Coculture Techniques ; Culture Media ; Cytokines/*immunology/secretion ; Dendritic Cells/cytology/*immunology/secretion ; Humans ; Hypersensitivity/immunology ; Interferon Type II/immunology/secretion ; Interleukin-10/immunology/secretion ; Interleukin-12/immunology/secretion ; Interleukin-5/immunology/secretion ; Lymphocyte Activation/immunology ; Mycobacterium bovis/*immunology ; Research Support, Non-U.S. Gov't ; Th2 Cells/cytology/immunology/secretion ; Up-Regulation/immunology

GITR (glucocorticoid-induced TNF receptor) is a recently identified member of the TNF receptor superfamily. The receptor is preferentially expressed on CD4+CD25+ regulatory T cells and GITR signals break the suppressive activity of the subset. In this study, we wanted to reveal the in vivo function of GITR in herpes simplex virus type 1 (HSV-1) infection. A single injection of anti-GITR mAb (DTA-1) immediately after viral infection significantly increased the number of CD4+ and CD8+ T cells expressing CD25, an activation surface marker, and secreting IFN-gamma. We confirmed these in vivo observations by showing ex vivo that re-stimulation of CD4+ or CD8+ T cells with a CD4+ or CD8+ T-cell-specific HSV-1 peptide, respectively, induced a significant elevation in cell proliferation and in IFN-gamma secretion. Our results indicate that GITR signals play a critical role in the T-cell immunity to HSV-1.
Animals ; Antibodies, Monoclonal/pharmacology ; CD4-Positive T-Lymphocytes/immunology ; CD8-Positive T-Lymphocytes/immunology ; Cell Proliferation ; Female ; Glucocorticoids/*pharmacology ; Herpes Simplex/*immunology ; Herpesvirus 1, Human/pathogenicity ; *Immunity, Cellular ; Interferon Type II/secretion ; *Lymphocyte Activation ; Mice ; Mice, Inbred BALB C ; Peptide Fragments/metabolism ; Receptors, Interleukin-2/metabolism ; Receptors, Nerve Growth Factor/genetics/immunology/*metabolism ; Receptors, Tumor Necrosis Factor/genetics/immunology/*metabolism ; Research Support, Non-U.S. Gov't ; T-Lymphocytes/*immunology/metabolism/virology

We demonstrated previously that Coptidis rhizoma extract (CRE) prevented S-nitroso-N-acetylpenicillamine-induced apoptotic cell death via the inhibition of mitochondrial membrane potential disruption and cytochrome c release in RINm5F (RIN) rat insulinoma cells. In this study, the preventive effects of CRE against cytokine-induced beta-cell death was assessed. Cytokines generated by immune cells infiltrating pancreatic islets are crucial mediators of beta-cell destruction in insulin-dependent diabetes mellitus. The treatment of RIN cells with IL-1beta and IFN-gamma resulted in a reduction of cell viability. CRE completely protected IL-1beta and IFN-gamma-mediated cell death in a concentration-dependent manner. Incubation with CRE induced a significant suppression of IL-1beta and IFN-gamma-induced nitric oxide (NO) production, a finding which correlated well with reduced levels of the iNOS mRNA and protein. The molecular mechanism by which CRE inhibited iNOS gene expression appeared to involve the inhibition of NF-kappa B activation. The IL-1beta and IFN-gamma-stimulated RIN cells showed increases in NF-kappa B binding activity and p65 subunit levels in nucleus, and IkappaBalpha degradation in cytosol compared to unstimulated cells. Furthermore, the protective effects of CRE were verified via the observation of reduced NO generation and iNOS expression, and normal insulin-secretion responses to glucose in IL-1beta and IFN-gamma-treated islets.
Animals ; Cell Death/drug effects ; Cell Line ; Cell Nucleus/metabolism ; Cell Survival/drug effects ; Drugs, Chinese Herbal/*pharmacology ; Gene Expression Regulation, Enzymologic/drug effects ; Glucose/pharmacology ; I-kappa B Proteins/metabolism ; Insulin/secretion ; Insulin-Secreting Cells/*cytology/*drug effects/enzymology ; Interferon-gamma/*pharmacology ; Interleukin-1beta/*pharmacology ; Male ; NF-kappa B/*metabolism ; Nitric Oxide/biosynthesis ; Nitric Oxide Synthase Type II/genetics/metabolism ; Protein Transport/drug effects ; RNA, Messenger/genetics/metabolism ; Rats ; Rats, Sprague-Dawley