title: Involvement of adhesion molecule in in vitro plaque-like formation of macrophages stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide.
abstract: OBJECTIVE
  Inflammatory agents, such as lipopolysaccharide (LPS), in periodontal pockets may promote atherogenesis by activating leukocytes. In our previous study, we developed a microchannel chip to observe the cell adhesion process in a fluid system. The objective of this investigation was to examine the mechanism by which periodontopathic bacterial LPS enhances plaque-like formation on a microchannel chip.
  
  
  METHODS
  To evaluate the effect of Aggregatibacter actinomycetemcomitans LPS on the expression of adhesion molecules, e.g. intercellular adhesion molecule 1 (ICAM-1), lymphocyte function-associated antigen 1 (LFA-1) and L-selectin, on the surface of murine macrophage RAW264.7 cells, the expression of each adhesion molecule was examined by flow cytometry and western blot analysis. Moreover, a flow test on the microchannel chip involving anti-adhesion molecule antibodies was conducted to clarify which adhesion molecule is related to plaque-like formation of RAW264.7 cells.
  
  
  RESULTS
  The expressions of ICAM-1 and LFA-1 on the surface of RAW 264.7 cells increased following 12 h culture with LPS; L-selectin expression was unaffected. An increase in ICAM-1 expression was also confirmed by western blot analysis. The flow test revealed that anti-ICAM-1 antibody inhibited plaque-like formation of LPS-stimulated macrophages on the micropillars of the microchannel chip.
  
  
  CONCLUSIONS
  These findings indicate that ICAM-1 plays an important role in plaque-like formation of LPS-stimulated macrophages. Our microchannel chip is a suitable tool for the investigation of etiological factors of atherosclerosis, including periodontitis, in vitro.
authors.affiliation: Division of Periodontology, Department of Cardiology and Periodontology, Kyushu Dental College, Kitakyushu, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tsutsumi
authors.forename: T
authors.initials: T
authors.lastname: Takeshi
authors.forename: K
authors.initials: K
authors.lastname: Nakashima
authors.forename: N
authors.initials: N
authors.lastname: Keisuke
authors.forename: T
authors.initials: T
authors.lastname: Isoda
authors.forename: I
authors.initials: I
authors.lastname: Takaaki
authors.forename: M
authors.initials: M
authors.lastname: Yokota
authors.forename: Y
authors.initials: Y
authors.lastname: Makoto
authors.forename: T
authors.initials: T
authors.lastname: Nishihara
authors.forename: N
authors.initials: N
authors.lastname: Tatsuji
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000502:physiology*; D000818:Animals; D000906:Antibodies; D050197:Atherosclerosis / Q000473:pathology; D015153:Blotting, Western; D002448:Cell Adhesion / Q000187:drug effects; D002449:Cell Aggregation / Q000187:drug effects; D018929:Cell Culture Techniques; D002460:Cell Line; D005434:Flow Cytometry; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis / Q000187:drug effects*; D019041:L-Selectin / Q000032:analysis / Q000187:drug effects*; D056656:Lab-On-A-Chip Devices; D008070:Lipopolysaccharides / Q000494:pharmacology*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects*; D051379:Mice
chemical_list: D000906:Antibodies; D008070:Lipopolysaccharides; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1; D019041:L-Selectin