ABSTRACT
PURPOSE: To determine the role of plasmacytoid dendritic cells (pDC) and myeloid dendritic cells (mDC) in priming effector T cells to induce allergy, and to evaluate the effect of immunostimulatory sequences (ISS, TLR9 agonist) on dendritic cells. METHODS: Cultured mDC and pDC with/without ISS were injected intratracheally into sensitized Balb/C mice. Mice were sacrificed, and then pulmonary function tests, bronchoalveolar lavage (BAL), cell counts, and cytokine levels were evaluated. Migration of dendritic cells was also evaluated after ISS administration. RESULTS: In mice injected with mDC, airway hyperresponsiveness, eosinophil counts, and Th2 cytokine levels in BAL increased with increasing numbers of mDC injected. However, in mice injected with pDC, none of these changed, suggesting poor priming of T cells by pDC. In addition, mDC pulsed with ISS inhibited asthmatic reactions, and ISS administration inhibited migration of DC to the lung. CONCLUSIONS: We suggest that pDC played a limited role in priming T cells in this asthma model and that mDC played a major role in inducing asthma. In addition, ISS inhibited migration of DC to the lung.
Subject(s)
Animals , Mice , Asthma , Bronchoalveolar Lavage , Cell Count , Dendritic Cells , Eosinophils , Hypersensitivity , Lung , Respiratory Function Tests , T-LymphocytesABSTRACT
Objective: To screen for the effective immunostimulatory sequences from hepatitis C virus (HCV) single strand RNA (ssRNA), and to identify the proteins that can bind to the sequences specifically. Methods: Four oligonucleotide sequences (HCV-. ORNs) derived from HCV ssRNA were synthesized, and the cytokines induced by them were detected using enzyme linked immunosorbent assay (ELISA), so as to identify the effective immunostimulatory sequences. Then proteins binding to the sequence(s) specifically were identified using improved electrophoresis mobility shift assay (EMSA) combined with electrospray ionization mass spectrum (ESI-MS). Results: One of the HCV-ORNs, ORN HCVtail, induced higher levels of TNF-α and IFN-α (P<0.01). Totally 83 groups of proteins were identified that can bind to ORNHCVtail; the proteins included TLR3 (Toll-like receptor 3), NLRC3 (NLR family, CARD domain-containing 3), and NLRC4 (NLR family, CARD domain-containing 4). Conclusion: We have successfully screened out effective immunostimulatory sequence of HCV ssRNA and the proteins that can bind to the sequence specifically. Our findings in the present study lay a foundation for mechanism research of immunity stimulated by HCV infection.
ABSTRACT
BACKGROUND AND OBJECTIVES: The classic immunotherapy has the inconvenience and the risk of anaphylaxis. Recent reports revealed that immunostimulatory DNA sequences (CpG motif, ISS-ODN) have been shown to act as strong Th1 response-inducing adjuvants and DNA based vaccination might be an effective therapeutic option for the treatment of allergic disease. In our study, we investigated whether ISS-ODN have anti-allergic effect in the mouse rhinitis model of Dermatophagoides farinae (Der f), the most common allergen in Korea. MATERIALS AND METHOD: C57BL/6 mice were sensitized with crude extract of Der f extract. After injection of ISS-ODN, several parameters of allergic response were evaluated. RESULTS: Injection with ISS-ODN suppressed itching symptom, eosinophilic infiltration into nasal mucosa and the splenic T cell proliferation after Der f allergen challenge in the murine model of allergic rhinitis. However, injection with ISS-ODN did not show a detectable Der f-specific IgE suppression. CONCLUSION: Our findings suggested ISS-ODN have an anti-allergic effect in the allergic rhinitis model of Der f allergen. House dust mite allergy can be reduced by the injection with ISS-ODN.
Subject(s)
Animals , Mice , Anaphylaxis , Base Sequence , Cell Proliferation , Dermatophagoides farinae , DNA , Eosinophils , Hypersensitivity , Immunoglobulin E , Immunotherapy , Korea , Nasal Mucosa , Pruritus , Pyroglyphidae , Rhinitis , VaccinationABSTRACT
Objective:To investigate the relationship between the immunostimulatory effects and the number of immunostimulatory sequence(ISS) in CpG immunostimulatory DNA.Methods:Mice were immunized by HAV inactive vaccine together with three kinds of CpG ODN which contains 2,4,8 ISS respectively by intraperitoneal injection. At the weeks 4,6,8 after immunization, peripheral blood was obtained from the tail vein of mice and assayed for anti HAV IgG by the fully automated microparticle enzymeimmunoassay.Results:The immunogenicity of HAV inactive vaccine can be boost up by CpG ODN which contains 2 ISS, CpG ODN which contains 4 ISS did not show any immunostimulatory effect, act as an adjuvant, but CpG ODN which contains 8 ISS showed inhibiting the immunological effect of the vaccine.Conclusion:Adequate length of CpG ODN(when it contains 2 ISS) can act as an effective immunostimulator adjuvant, and it might decrease the immunogenicity of the vaccine if it contains much more ISS.
ABSTRACT
Objective: To screen out DNA binding proteins specifically recognizing CpG immunostimulatory sequence (ISS) for further investigating the molecular mechanisms of ISS. Methods: Yeast one hybrid system was adapted in screening a human bone marrow cDNA library using 4 copies of ISS as bait. The ISS binding activity of the positive clone was confirmed by electrophoretic mobility shift assay (EMSA). Results: Four dual positive colonies were obtained, two of them encoded proteins with unknown functions. The other 2 encoded light chains of immunoglobulin with amino sequences homology to anti DNA Ab and HBsAb respectively. EMSA showed HBsAb specifically bound to CpG ODN at pH6.4 and pH 5.8. Conclusion: HBsAb may have ISS specific DNA binding activity.