27 August 2003
Expression and involvement of Toll-like receptors (TLR)2, TLR4, and CD14 in monocyte TNF-alfa production induced by lipopolysaccharides from Neisseria meningitidis
Mohammad Reza Mirlashari, Torstein LybergMed Sci Monit 2003; 9(8): BR316-324 :: ID: 13093
Abstract
Background:The present study was undertaken to examine the ability of lipopolysaccharide-containing outer membrane vesicles (OMV-LPS) and purified LPS (P-LPS) from the same meningococcal strain to induce the expression of Toll-like receptors (TLR2 and TLR4) and TNF-alfa production in leukocytes, and further to study the involvement of TLRs, and CD14 in monocyte TNF- alfa production in an ex vivo human whole blood system.Material/Methods:OMV-LPS or P-LPS were added to human whole blood and expression of TLR2/4 and production of TNF- alfa in leukocytes were measured by flow cytometry. To study involvement of TLRs and CD14 in monocyte cytokine production we used monoclonal antibodies against TLR2/4 and CD14.Results:OMV-LPS and P-LPS induced surface expression (maximal at 120 min) of TLR2 and TLR4 on granulocytes and monocytes. LPS incorporated in OMV was less potent (weight basis) than P-LPS in inducing monocyte TNF- alfa production. When inducing monocyte TNF-alfa by OMV-LPS, antibodies directed against TLR2 and TLR4 caused 45 and 78% inhibition, respectively. When inducing TNF- alfa by P-LPS, antibodies against TLR2 had no effect, whereas anti-TLR4 antibodies caused 63% inhibition. Antibodies against CD14 inhibited nearly completely the monocyte TNF- alfa response induced by meningococcal LPS irrespective of whether LPS was presented in purified form or incorporated in membrane vesicles.Conclusions:OMV-LPS and P-LPS from the same meningococcal strain induced expression of TLR2/4 on monocytes and granulocytes. Surface receptors TLR2/4 and CD14 are essential for in vitro cellular activation induced by OMV-LPS and P-LPS, but the functional significance of these receptors during meningococcal infections remains elusive.
Keywords: Antigens, CD14 - metabolism, Lipopolysaccharides - metabolism, Membrane Glycoproteins - metabolism, Monocytes - drug effects, Monocytes - metabolism, Neisseria meningitidis - cytology, Neisseria meningitidis - metabolism, Receptors, Cell Surface - metabolism, Toll-Like Receptor 2, Toll-Like Receptor 4, Toll-Like Receptors, Tumor Necrosis Factor-alpha - metabolism
962 221
Editorial
01 December 2023 : Editorial
Editorial: Outbreaks of Post-Pandemic Childhood Pneumonia and the Re-Emergence of Endemic Respiratory InfectionsDOI: 10.12659/MSM.943312
Med Sci Monit 2023; 29:e943312
In Press
04 Dec 2023 : Animal Research
Effects of Intrathecal Ketamine on Cerebrospinal Fluid Levels of Brain-Derived Neurotrophic Factor and Mech...Med Sci Monit In Press; DOI:
01 Dec 2023 : Clinical Research
Risk Factors and Clinical Outcomes of COVID-19 Infection in Multiple Sclerosis Patients: A Retrospective St...Med Sci Monit In Press; DOI:
30 Nov 2023 : Review article
Decoding the Neurological Sequelae of General Anesthesia: A ReviewMed Sci Monit In Press; DOI:
30 Nov 2023 : Clinical Research
Enhanced Pain Relief and Muscle Growth in Individuals with Low Back Instability: The Impact of Blood Flow R...Med Sci Monit In Press; DOI:
Most Viewed Current Articles
13 Nov 2021 : Clinical Research
Acceptance of COVID-19 Vaccination and Its Associated Factors Among Cancer Patients Attending the Oncology ...DOI :10.12659/MSM.932788
Med Sci Monit 2021; 27:e932788
30 Dec 2021 : Clinical Research
Retrospective Study of Outcomes and Hospitalization Rates of Patients in Italy with a Confirmed Diagnosis o...DOI :10.12659/MSM.935379
Med Sci Monit 2021; 27:e935379
14 Dec 2022 : Clinical Research
Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase LevelsDOI :10.12659/MSM.937990
Med Sci Monit 2022; 28:e937990
08 Mar 2022 : Review article
A Review of the Potential Roles of Antioxidant and Anti-Inflammatory Pharmacological Approaches for the Man...DOI :10.12659/MSM.936292
Med Sci Monit 2022; 28:e936292