title: Mammalian cell survival and processing in supercritical CO(2).
abstract: We demonstrate that mammalian cells can survive for 5 min within high-pressure CO(2)(.) Cell survival was investigated by exposing a range of mammalian cell types to supercritical CO(2) (scCO(2)) (35 degrees C, 74 bar; 1 bar = 100 kPa) for increasing exposure and depressurization times. The myoblastic C2C12 cell line, 3T3 fibroblasts, chondrocytes, and hepatocytes all displayed appreciable but varying metabolic activity with exposure times up to 1 min. With depressurization times of 4 min, cell population metabolic activity was >/=70% of the control population. Based on survival data, we developed a single-step scCO(2) technique for the rapid production of biodegradable poly(dl-lactic acid) scaffolds containing mammalian cells. By using optimum cell-survival conditions, scCO(2) was used to process poly(dl-lactic acid) containing a cell suspension, and, upon pressure release, a polymer sponge containing viable mammalian cells was formed. Cell functionality was demonstrated by retention of an osteogenic response to bone morphogenetic protein-2 in C2C12 cells. A gene microarray analysis showed no statistically significant changes in gene expression across 4,418 genes by a single-class t test. A significance analysis of microarrays revealed only eight genes that were down-regulated based on a delta value of 1.0125 and a false detection rate of 0.
authors.affiliation: Schools of Pharmacy and Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Ginty
authors.forename: Daniel
authors.initials: D
authors.lastname: Howard
authors.forename: Felicity R A J
authors.initials: FR
authors.lastname: Rose
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Whitaker
authors.forename: John J A
authors.initials: JJ
authors.lastname: Barry
authors.forename: Patrick
authors.initials: P
authors.lastname: Tighe
authors.forename: Stacey R
authors.initials: SR
authors.lastname: Mutch
authors.forename: Gulay
authors.initials: G
authors.lastname: Serhatkulu
authors.forename: Richard O C
authors.initials: RO
authors.lastname: Oreffo
authors.forename: Steven M
authors.initials: SM
authors.lastname: Howdle
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Shakesheff
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000494:pharmacology*; D002454:Cell Differentiation; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects; D012756:Sheep
chemical_list: D002245:Carbon Dioxide