title: Oxygen consumption in T-47D cells immobilized in alginate.
abstract: OBJECTIVE
  Encapsulation or entrapment of cells is increasingly being used in a wide variety of scientific studies for tissue engineering and development of novel medical devices. The effect on cell metabolism of such systems is, in general, not well characterized. In this work, a simple system for monitoring respiration of cells embedded in 3-D alginate cultures was characterized.
  
  
  METHODS
  T-47D cells were cultured in alginate gels. Oxygen concentration curves were recorded within cell-gel constructs using two different sensor systems, and cell viability and metabolic state were characterized using confocal microscopy and commercially available stains.
  
  
  RESULTS
  At sufficient depth within constructs, recorded oxygen concentration curves were not significantly influenced by influx of oxygen through cell-gel layers and oxygen consumption rate could be calculated simply by dividing oxygen loss in the system per time, by the number of cells. This conclusion was supported by a 3-D numeric simulation. For the T-47D cells, the oxygen consumption rate was found to be 61 ± 6 fmol/cell/h, 3-4 times less than has previously been found for these cells, when grown exponentially in monolayer culture.
  
  
  CONCLUSIONS
  The experimental set-up presented here may be varied in multiple ways by changing the cell-gel construct 3-D microenvironment, easily allowing investigation of a variety of factors on cell respiration.
authors.affiliation: School of Pharmacy, Universiy of Oslo, Oslo, 0316, Norway. b.e.larsen@farmasi.uio.no
authors.forename: B E
authors.initials: BE
authors.lastname: Larsen
authors.forename: J A
authors.initials: JA
authors.lastname: Sandvik
authors.forename: J
authors.initials: J
authors.lastname: Karlsen
authors.forename: E O
authors.initials: EO
authors.lastname: Pettersen
authors.forename: J E
authors.initials: JE
authors.lastname: Melvik
mesh_terms: D000464:Alginates / Q000378:metabolism*; D018929:Cell Culture Techniques / Q000379:methods*; D002460:Cell Line; D019069:Cell Respiration / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D006801:Humans; D000860:Hypoxia / Q000378:metabolism / Q000503:physiopathology; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D010100:Oxygen