title: Effects of perfusion and cyclic compression on in vitro tissue engineered meniscus implants.
abstract: OBJECTIVE
  The purpose of this study was to investigate the influence of continuous perfusion and mechanical stimulation on bone marrow stromal cells seeded on a collagen meniscus implant.
  
  
  METHODS
  Bone marrow aspirates from 6 donors were amplified in vitro. 10(6) human BMSC were distributed on a collagen meniscus implant. Scaffolds were cultured under static conditions (control) or placed into a bioreactor system where continuous perfusion (10 ml/min) or perfusion and mechanical stimulation (8 h of 10% cyclic compression at 0.5 Hz) were administered daily. After 24 h, 7 and 14 days, cell proliferation, synthesis of procollagen I and III peptide (PIP, PIIIP), histology, and the equilibrium modulus of the constructs were analyzed.
  
  
  RESULTS
  Proliferation demonstrated a significant increase over time in all groups (p < 0.001). PIP synthesis was found to increase from 0.1 ± 0.0 U/ml/g protein after 24 h to 2.0 ± 0.5 (perfusion), 3.8 ± 0.3 (mechanical stimulation), and 1.8 ± 0.2 U/ml/g protein (static control, lower than perfusion and mechanical stimulation, p < 0.05). These differences were also evident after 2 weeks (2.7 ± 0.3, 4.0 ± 0.6, and 1.8 ± 0.2 U/ml/g protein, p < 0.01); PIIIP synthesis was found to increase from 0.1 ± 0.0 U/ml/g protein after 24 h to 2.9 ± 0.7 (perfusion), 3.1 ± 0.9 (mechanical stimulation), and 1.6 ± 0.3 U/ml/g protein (controls) after 1 week and remained significantly elevated under the influence of perfusion and mechanical stimulation (p < 0.01) after 2 weeks. Mechanical stimulation increased the equilibrium modulus more than static culture and perfusion after 2 weeks (24.7 ± 7.6; 12.3 ± 3.7; 15.4 ± 2.6 kPa; p < 0.02).
  
  
  CONCLUSIONS
  Biomechanical stimulation and perfusion have impact on collagen scaffolds seeded with BMSCs. Cell proliferation can be enhanced using continuous perfusion and differentiation is fostered by mechanical stimulation.
authors.affiliation: Trauma Department, Hanover Medical School (MHH), OE 6230, Carl-Neuberg-Straße 1, 30625 Hannover, Germany. petri.maximilian@mh-hannover.de
authors.forename: M
authors.initials: M
authors.lastname: Petri
authors.forename: K
authors.initials: K
authors.lastname: Ufer
authors.forename: I
authors.initials: I
authors.lastname: Toma
authors.forename: C
authors.initials: C
authors.lastname: Becher
authors.forename: E
authors.initials: E
authors.lastname: Liodakis
authors.forename: S
authors.initials: S
authors.lastname: Brand
authors.forename: P
authors.initials: P
authors.lastname: Haas
authors.forename: C
authors.initials: C
authors.lastname: Liu
authors.forename: B
authors.initials: B
authors.lastname: Richter
authors.forename: C
authors.initials: C
authors.lastname: Haasper
authors.forename: G
authors.initials: G
authors.lastname: von Lewinski
authors.forename: M
authors.initials: M
authors.lastname: Jagodzinski
mesh_terms: D001696:Biomechanical Phenomena; D019149:Bioreactors; D001854:Bone Marrow Cells / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism; D006801:Humans; D008592:Menisci, Tibial / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D010477:Perfusion; D011312:Pressure; D011347:Procollagen / Q000378:metabolism; D011863:Radioimmunoassay; D017154:Stromal Cells / Q000502:physiology; D023822:Tissue Engineering; D054457:Tissue Scaffolds
chemical_list: D011347:Procollagen; D003094:Collagen