title: Effect of magnetic field on the fibronectin adsorption, cell attachment and proliferation on titanium surface.
abstract: OBJECTIVE
  We studied the effect of various static magnetic fields (SMFs) on the adsorption of specific recombinant fibronectin (FN) peptide (hFNIII9-10) on the titanium surface. Furthermore, the responses of human osteosarcoma TE-85 cells in the SMF were observed.
  
  
  METHODS
  Various magnetic fields--1, 2, 3, 5, 7, 10 mT--were established by controlling the distance from Nd-Fe-B magnet to the disks. For FN adsorption experiment, machined titanium disks were incubated in 1 microM hFNIII9-10 at 37 degrees C overnight under magnetic field. The adsorbed hFNIII9-10 was measured as optical density (OD). For attachment study, TE-85 cells were incubated for 2 h on the hFNIII9-10 coated machined titanium disks and OD values were measured. As for proliferation study, titanium disks were incubated for 48 h after washing unattached cells in 2 h. The amount of proliferated TE-85 cell was also measured as OD value. Attachments of TE-85 cells under various intensities of magnetic field were observed using a scanning electron microscope.
  
  
  RESULTS
  The amount of adsorbed hFNIII9-10 showed no significant difference between control (0 mT) and six experimental groups (1, 2, 3, 5, 7, 10 mT). However, TE-85 cells attached significantly higher in groups of 1, 2, 5, 10 mT than in control group (P=0). Cell attachment in groups of 3, 7 mT showed no significant difference with that of control group. TE-85 cells were observed to attach through filopodia. Especially in 1 mT, flattened cells were predominant. In proliferation assay, 1 mT stimulated TE-85 cells showed significantly higher proliferation than those in 2, 3 and 7 mT (P=0).
  
  
  CONCLUSIONS
  Magnetic fields under 10 mT did not influence FN adsorption on the titanium surface. However, a significant effect was found on cell attachment and proliferation.
authors.affiliation: Department of Prosthodontics, College of Dentistry, Seoul National University, Seoul, South Korea.
authors.forename: Hyo Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Ik Tae
authors.initials: IT
authors.lastname: Chang
authors.forename: Seong Joo
authors.initials: SJ
authors.lastname: Heo
authors.forename: Jai Young
authors.initials: JY
authors.lastname: Koak
authors.forename: Seong Kyun
authors.initials: SK
authors.lastname: Kim
authors.forename: Jun Hyeog
authors.initials: JH
authors.lastname: Jang
mesh_terms: D000327:Adsorption; D000704:Analysis of Variance; D049109:Cell Proliferation; D005353:Fibronectins / Q000493:pharmacokinetics*; D006801:Humans; D011827:Radiation; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D005353:Fibronectins; C501364:fibronectin type III like peptide, human; D014025:Titanium