title: Granulocyte-macrophage colony-stimulating factor amplification of interleukin-1beta and tumor necrosis factor alpha production in THP-1 human monocytic cells stimulated with lipopolysaccharide of oral microorganisms.
abstract: Cytokines, including granulocyte-macrophage colony-stimulating factor (GM-CSF), are used to assist in bone marrow recovery during cancer chemotherapy. Interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) play important roles in inflammatory processes, including exacerbation of periodontal diseases, one of the most common complications in patients who undergo this therapy. A human monocyte cell line (THP-1) was utilized to investigate IL-1beta and TNF-alpha production following GM-CSF supplementation with lipopolysaccharide (LPS) from two oral microorganisms, Porphyromonas gingivalis and Fusobacterium nucleatum. LPS of P. gingivalis or F. nucleatum was prepared by a phenol-water extraction method and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and determination of total protein and endotoxin contents. Resting THP-1 cells were treated with LPS of P. gingivalis or F. nucleatum and/or GM-CSF (50 IU/ml) by using different concentrations for various time periods. Production of IL-1beta and TNF-alpha in THP-1 cells was measured by solid-phase enzyme-linked immunosorbent assay. Reverse transcription (RT)-PCR was used to evaluate the gene expression of resting and treated THP-1 cells. IL-1beta was not detected in untreated THP-1 cells. IL-1beta production was, however, stimulated sharply at 4 h. GM-CSF amplified IL-1beta production in THP-1 cells treated with LPS from both oral anaerobes. No IL-1beta-specific mRNA transcript was detected in untreated THP-1 cells. However, IL-1beta mRNA was detected by RT-PCR 2 h after stimulation of THP-1 cells with LPS from both organisms. GM-CSF did not shorten the IL-1beta transcriptional activation time. GM-CSF plus F. nucleatum or P. gingivalis LPS activated THP-1 cells to produce a 1.6-fold increase in TNF-alpha production at 4 h over LPS stimulation alone. These investigations with the in vitro THP-1 model indicate that there may be an increase in the cellular immune response to oral endotoxin following GM-CSF therapy, as evidenced by production of the tissue-reactive cytokines IL-1beta and TNF-alpha.
authors.affiliation: Department of Oral Medicine, Dental School, University of Maryland, Baltimore 21201, USA. aab001@dental.umaryland.edu
authors.forename: A A
authors.initials: AA
authors.lastname: Baqui
authors.forename: T F
authors.initials: TF
authors.lastname: Meiller
authors.forename: J J
authors.initials: JJ
authors.lastname: Chon
authors.forename: B F
authors.initials: BF
authors.lastname: Turng
authors.forename: W A
authors.initials: WA
authors.lastname: Falkler
mesh_terms: D001438:Bacteroidaceae / Q000276:immunology*; D004305:Dose-Response Relationship, Drug; D016967:Fusobacterium nucleatum / Q000276:immunology / Q000302:isolation & purification; D005786:Gene Expression Regulation; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000235:genetics; D008070:Lipopolysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D009000:Monocytes / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D016966:Porphyromonas gingivalis / Q000276:immunology / Q000302:isolation & purification; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D007375:Interleukin-1; D008070:Lipopolysaccharides; D012329:RNA, Bacterial; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D016178:Granulocyte-Macrophage Colony-Stimulating Factor