FUNCTIONAL-CHANGES IN THP-1 HUMAN MONOCYTIC CELLS AFTER STIMULATION WITH LIPOPOLYSACCHARIDE OF ORAL MICROORGANISMS AND GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR

A human THP-1 monocyte cell line culture: system has been utilized to observe the effect of granulocyte macrophage colony stimulating factor (GM-CSF) supplementation with lipopolysaccharide (LPS) of oral microo rganisms to stimulate monocyte/macrophage functional activity. LPS of oral microorganisms, Fusobacterium nucleatum and Porpyhyromonas gingiv alis was produced by phenol-water extraction and characterized. The ph agocytosis assay was performed using FITC labeled Saccharomyces yeast particles. Phagocytic functional activity was observed in 10-11% of re sting THP-1 cells. Treatment of THP-1 cells with LPS of F. nucleatum o r P. gingivalis increased the phagocytic activity of THP-1 cells 2-3 f old. GM-CSF significantly increased phagocytosis either alone or when supplemented with LPS off. nucleatum or P. gingivalis. A chemotaxis as say was performed using a 48 well chemotaxis chamber. Chemotactic func tional activity of THP-1 cells was increased 2-fold after 4 days of tr eatment with GM-CSF. Stimulation of THP-1 cells with LPS of F. nucleat um or P. gingivalis significantly reduced the chemotactic activity ind icating the maturation towards a fixed macrophage. There were function al variations (chemotaxis and phagocytosis) in THP-1 cells in response to LPS of oral microorganisms following stimulation with GM-CSF.