ABSTRACT
Anti-cancer drug bleomycin (BLM) can cause acute lung injury (ALI) which often results in pulmonary fibrosis due to a failure of resolving acute inflammatory response. The aim of this study is to investigate whether toll-like receptor (TLR) 2 mediates BLM-induced ALI, inflammation and fibrosis. BLM-induced dendritic cells (DCs) maturation was analyzed by flow cytometry and cytokine secretion was detected by the ELISA method. The expression and activity of p38 and ERK MAPK were determined with Western blotting. The roles of TLR2 in ALI, inflammation and fibrosis were investigated in C57BL/6 mice administered intratracheally with BLM. The results demonstrated that BLM-administered mice had higher expression of TLR2 (P<0.001) and its signaling molecules. Blocking TLR2 significantly inhibited the maturation of DCs and reversed BLM-stimulated secretion of cytokines in DCs, such as IL-6 (P<0.001), IL-17 (P<0.05) and IL-23 (P<0.05). TLR2 inhibition attenuated BLM-induced increase of inflammatory cells in bronchoalveolar lavage fluid (BALF), and reversed the immunosuppressive microenvironment by enhancing TH1 response (P<0.05) and inhibiting TH2 (P<0.001), Treg (P<0.01) and TH17 (P<0.01) responses. Importantly, blocking TLR2 in vivo significantly protected BLM-administered mice from pulmonary injury, inflammation and fibrosis and subsequently increased BLM-induced animal survival (from 50% to 92%). Therefore, TLR2 is a novel potential target for ALI and pulmonary fibrosis.
Subject(s)
Animals , Male , Mice , Acute Lung Injury , Metabolism , Pathology , Bleomycin , Toxicity , Bronchoalveolar Lavage Fluid , Cells, Cultured , Cytokines , Bodily Secretions , Dendritic Cells , Cell Biology , Metabolism , Inflammation , Metabolism , Pathology , Interleukin-17 , Bodily Secretions , Interleukin-23 , Bodily Secretions , Interleukin-6 , Bodily Secretions , Lung , Metabolism , MAP Kinase Signaling System , Mice, Inbred C57BL , Pulmonary Fibrosis , Metabolism , Pathology , T-Lymphocytes, Regulatory , Th1 Cells , Th2 Cells , Toll-Like Receptor 2 , Metabolism , PhysiologyABSTRACT
Altered peptide ligand (APL), a short peptide with immune regulatory activity and substitutions of a single or multiple amino acids in an antigenic peptide, has shown potential therapeutic effect on autoimmune disease, tumor and virus infection. APL regulates immune responses by interfering the interaction between the major histocompatibility complex (MHC), antigenic peptide and T cell receptor (TCR), or by regulating the intracellular signaling of antigen presenting cells, bystander suppression and inducing heterogenous immune responses. High-specific and high-affinity APL screened from peptide laboratory by phage display, has a potential to be a new resource for drug with antigen specificity.
Subject(s)
Animals , Humans , Antigen-Presenting Cells , Allergy and Immunology , Metabolism , Autoimmune Diseases , Allergy and Immunology , Therapeutics , Immunotherapy , Methods , Ligands , Major Histocompatibility Complex , Allergy and Immunology , Peptide Fragments , Allergy and Immunology , Metabolism , Therapeutic Uses , Peptide Library , Receptors, Antigen, T-Cell , Allergy and Immunology , MetabolismABSTRACT
<p><b>AIM</b>To study the effects of ginsenoside-Ro on cell proliferation and cytokine production in murine splenocytes.</p><p><b>METHODS</b>The effect of ginsenoside-Ro on murine splenocytes proliferation was studied using [3H] thymidine incorporation assay. Effects of ginsenoside-Ro on the production of cytokines interleukin-2 (IL-2), interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) from murine splenocytes were detected by ELISA method. Effects of ginsenoside-Ro on mRNA level of Th1 cytokine IFN-gamma and Th2 cytokine IL-4 were evaluated by reverse transcription polymerase chain reaction (RT-PCR) analysis.</p><p><b>RESULTS</b>Ginsenoside-Ro showed no mitogenic effect on unstimulated murine splenocytes. It enhanced the proliferation of Con A-induced murine splenocytes and the production of IL-2 at concentrations of 1-10 micromol x L(-1). Moreover, ginsenoside-Ro increased the production and expression of Th2 cytokine IL-4 and decreased the production and expression of Th1 cytokine IFN-gamma in Con A-induced murine splenocytes at concentrations of 2-10 micromol x L(-1).</p><p><b>CONCLUSION</b>Ginsenoside-Ro showed immunomodulatory effects by regulating the production and expression of Th1/Th2 cytokines in murine splenocytes.</p>