ABSTRACT
Pseudomonas aeruginosa (PA) can cause infections in compromised hosts by interacting with the glycocalyx of host epithelial cells. It binds to glycostructures on mucosal surfaces via two lectins, which are carbohydrate-binding proteins, named PA-IL and PA-IIL, and blocking this interaction is, thus, an attractive anti-adhesive strategy. The aim of this study was to determine by ciliary beat frequency (CBF) analysis whether monosaccharides or peptides mimicking glycostructures represent blockers of PA lectin binding to human airway cilia. The treatment with monosaccharides and peptides alone did not change the CBF compared to controls and the tested compounds did not influence the cell morphology or survival, with the exception of peptide pOM3. PA-IL caused a decrease of the CBF within 24 h. D-galactose as well as the peptides mimicking HNK-1, polysialic acid and fucose compensated the CBF-modulating effect of PA-IL with different affinities. PA-IIL also bound to the human airway cilia in cell culture and resulted in a decrease of the CBF within 24 h. L(-)-fucose and pHNK-1 blocked the CBF-decreasing effect of PA-IIL. The HNK-1-specific glycomimetic peptide had a high affinity for binding to both PA-IL and PA-IIL, and inhibited the ciliotoxic effect of both lectins, thus, making it a strong candidate for a therapeutic anti-adhesive drug.
Subject(s)
Cilia/drug effects , Lectins/antagonists & inhibitors , Monosaccharides/pharmacology , Peptides/pharmacology , Pseudomonas aeruginosa/metabolism , Adhesins, Bacterial/metabolism , Amino Acid Sequence , Bacterial Adhesion/drug effects , Bacterial Proteins/metabolism , Binding Sites , Bronchi/metabolism , Bronchi/microbiology , CD57 Antigens/chemistry , CD57 Antigens/metabolism , Cilia/metabolism , Fucose/chemistry , Fucose/metabolism , Galactose/chemistry , Galactose/metabolism , Humans , Lectins/metabolism , Molecular Mimicry , Molecular Sequence Data , Peptides/chemistry , Pseudomonas aeruginosa/pathogenicityABSTRACT
OBJECTIVE: The pathogenesis of granulomatous inflammation in the respiratory tract and autoimmunity in Wegener granulomatosis (WG) are poorly understood. Since mucociliar clearance represents the first major line of defence in the respiratory tract and its breakdown facilitates chronic inflammation, we investigated ciliary beat frequency (CBF) in WG. METHODS: Nasal epithelial cells were obtained from 30 patients with WG with involvement of the upper respiratory tract, 12 patients with other inflammatory rheumatic disease and 10 healthy controls. CBF was measured at 5 and 24 h after collection. RESULTS: were correlated with clinical data. Results: CBF was significantly reduced in WG compared to disease and healthy controls after 5 and 24 h. In WG, CBF almost stagnated after 24 h. Reduction of CBF correlated with the cumulative number of immunosuppressive agents in WG, but not in disease controls. No correlation was found between CBF impairment and cyclophosphamide levels, disease extent, disease activity, disease duration, serological and microbiological findings, or inflammation markers. CONCLUSION: CBF is severely impaired in WG, potentially influenced by immunosuppressive treatment. To what extent CBF impairment and subsequent barrier dysfunction are caused by other factors still has to be elucidated. Supportive measures to improve mucociliary clearance should be discussed in patients with WG.
Subject(s)
Cilia/physiology , Granulomatosis with Polyangiitis/physiopathology , Nasal Mucosa/ultrastructure , Analysis of Variance , Autoimmunity/physiology , Case-Control Studies , Cilia/ultrastructure , Female , Granulomatosis with Polyangiitis/drug therapy , Granulomatosis with Polyangiitis/pathology , Humans , Immunosuppressive Agents/therapeutic use , Male , Microscopy, Electron , Middle Aged , Mucociliary Clearance , Nasal Mucosa/pathology , Time FactorsSubject(s)
Retinal Diseases/congenital , Child , Diagnosis, Differential , Humans , Male , Membranes , Retinal Diseases/diagnosisABSTRACT
Human placental soluble and solubilized mitochondrial hexokinase was partly purified by column chromatography and the kinetic properties were determined. Based on this data, on the chromatographic behaviour and on heat stability experiments, it is concluded that soluble and particle-bound hexokinase are of the same isoenzyme type, presumably type I, in placenta.
Subject(s)
Hexokinase/metabolism , Placenta/enzymology , Cytosol/enzymology , Female , Hexokinase/isolation & purification , Humans , Kinetics , Mitochondria/enzymology , PregnancyABSTRACT
The enzymes hexokinase (HK), phosphoglucomutase (PGM), pyruvate kinase (PK) and lactate dehydrogenase (LDH) were assayed in villous tissue homogenates and cell fractions of normal human term placentas. Although lowest in activity and probably rate limiting in glycolysis, hexokinase is theoretically adequate to phosphorylate the total amount of glucose metabolized. PGM and PK activity were in the same range exceeding HK by 10-15 times, suggesting a largely increased breakdown of glycogen-derived glucose in situations of need. Substantially higher LDH activities may reflect the placental ability to utilize lactate from both mother and fetus. Of all enzymes only hexokinase was found to be associated with the particulate matter in considerable amounts.
