title: Quantitative analysis of gene expression in human articular chondrocytes assigned for autologous implantation.
abstract: Autologous chondrocyte implantation (ACI) relies on the implantation of in vitro expanded cells. The aim was to study the dedifferentiation of human articular chondrocytes under different cultivating conditions [days 0-10 in the primary culture (P0); passages in a monolayer from P0 to P3; monolayer vs. alginate and monolayer vs. alginate/agarose hydrogels] using real-time PCR analysis. The relative gene expressions for collagen type I and II, aggrecan and versican were quantified and the corresponding differentiation indexes (Col2/Col1, Agr/Ver) were calculated. The values of both differentiation indexes decreased exponentially with time in the P0 monolayer culture, and continued with a significant decrease over the subsequent monolayer passages. On the contrary, the chondrocytes seeded in either of the hydrogels significantly increased the indexes compared to their parallel monolayer cultures. These results indicate that alginate and alginate/agarose hydrogels offer an appropriate environment for human articular chondrocytes to redifferentiate after being expanded in vitro. Therefore the three-dimensional (3D) hydrogel chondrocyte cultures present not only surgical, but also biological advantage over the classic suspension-periosteum chondrocyte implantation.
authors.affiliation: Educell d.o.o., Slajmerjeva 6, SI-1000 Ljubljana, Slovenia. ariana.barlic@educell.si
authors.forename: Ariana
authors.initials: A
authors.lastname: Barlic
authors.forename: Matej
authors.initials: M
authors.lastname: Drobnic
authors.forename: Elvira
authors.initials: E
authors.lastname: Malicev
authors.forename: Nevenka
authors.initials: N
authors.lastname: Kregar-Velikonja
mesh_terms: D000328:Adult; D053674:Aggrecans / Q000235:genetics; D000464:Alginates; D002358:Cartilage, Articular / Q000166:cytology*; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000502:physiology* / Q000637:transplantation*; D024042:Collagen Type I / Q000235:genetics; D024043:Collagen Type II / Q000235:genetics; D003470:Culture Media; D020869:Gene Expression Profiling; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D066298:In Vitro Techniques; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012685:Sepharose; D014182:Transplantation, Autologous; D053675:Versicans / Q000235:genetics
chemical_list: D053674:Aggrecans; D000464:Alginates; D024042:Collagen Type I; D024043:Collagen Type II; D003470:Culture Media; D006603:Hexuronic Acids; D053675:Versicans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020723:Glucuronic Acid; D012685:Sepharose