ABSTRACT
Background: The immune system functions to protect the host from a broad array of infectious diseases. Here, we evaluated the in vitro immunomodulatory effects of green coffee extract (GCE), and conducted a double-blinded, randomized and placebo-controlled trial among apparently healthy individuals. Methods: We determined the levels and functions of inflammatory and immune markers viz., phospho-NF-κB p65 ser536, chemotaxis, phagocytosis, TH1/TH2 cytokines and IgG production. We also evaluated several immunological markers such as total leukocyte counts, differential leukocyte counts, NK cell activity, CD4/CD8 ratio, serum immunoglobulin, C-reactive protein (CRP) and pro-inflammatory cytokines (IL-6 and TNF-α). Results and conclusion: GCE significantly inhibited LPS-induced NF-κB p65 ser536 phosphorylation, MCP-1-induced chemotaxis and significantly enhanced phagocytosis and IgG production. In addition, GCE modulated PMA/PHA-induced TH1/TH2 cytokine production. Clinical investigations suggested that the expression of CD56 and CD16 was markedly augmented on NK cells following GCE treatment. GCE significantly enhanced IgA production before and after influenza vaccination. Similarly, IL-6, TNF-α and CRP levels were significantly inhibited by GCE. Together, GCE confers several salubrious immunomodulatory effects at different levels attributing to optimal functioning of immune responses in the host. Taxonomy: Cell biology, Clinical study, Clinical Trial.
ABSTRACT
The role of pleiotrophin in fetal lung development was investigated. We found that pleiotrophin and its receptor, protein-tyrosine phosphatase receptor beta/zeta, were highly expressed in mesenchymal and epithelial cells of the fetal lungs, respectively. Using isolated fetal alveolar epithelial type II cells, we demonstrated that pleiotrophin promoted fetal type II cell proliferation and arrested type II cell trans-differentiation into alveolar epithelial type I cells. Pleiotrophin also increased wound healing of injured type II cell monolayer. Knockdown of pleiotrophin influenced lung branching morphogenesis in a fetal lung organ culture model. Pleiotrophin increased the tyrosine phosphorylation of beta-catenin, promoted beta-catenin translocation into the nucleus, and activated T cell factor/lymphoid enhancer factor transcription factors. Dlk1, a membrane ligand that initiates the Notch signaling pathway, was identified as a downstream target of the pleiotrophin/beta-catenin pathway by endogenous dlk1 expression, promoter assay, and chromatin immunoprecipitation. These results provide evidence that pleiotrophin regulates fetal type II cell proliferation and differentiation via integration of multiple signaling pathways including pleiotrophin, beta-catenin, and Notch pathways.
Subject(s)
Carrier Proteins/pharmacology , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cytokines/pharmacology , Epithelial Cells/drug effects , Epithelial Cells/physiology , Intercellular Signaling Peptides and Proteins/metabolism , Lung , Membrane Proteins/metabolism , beta Catenin/metabolism , Animals , Cells, Cultured , Epithelial Cells/cytology , Female , Fetus/anatomy & histology , Intercellular Signaling Peptides and Proteins/genetics , Lung/anatomy & histology , Lung/embryology , Membrane Proteins/genetics , Morphogenesis/drug effects , Pregnancy , Promoter Regions, Genetic , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Rats , Receptor-Like Protein Tyrosine Phosphatases, Class 5/genetics , Receptor-Like Protein Tyrosine Phosphatases, Class 5/metabolism , Signal Transduction/physiology , TCF Transcription Factors/metabolism , Tissue Culture Techniques , beta Catenin/geneticsABSTRACT
BACKGROUND: Lamellar bodies are lysosome-related secretory granules and store lung surfactant in alveolar type II cells. To better understand the mechanisms of surfactant secretion, we carried out proteomic analyses of lamellar bodies isolated from rat lungs. RESULTS: With peptide mass fingerprinting by Matrix Assisted Laser Desorption/Ionization - Time of Flight mass spectrometry, 44 proteins were identified with high confidence. These proteins fell into diverse functional categories: surfactant-related, membrane trafficking, calcium binding, signal transduction, cell structure, ion channels, protein processing and miscellaneous. Selected proteins were verified by Western blot and immunohistochemistry. CONCLUSION: This proteomic profiling of lamellar bodies provides a basis for further investigations of functional roles of the identified proteins in lamellar body biogenesis and surfactant secretion.