title: Effects of culture on PAMPS/PDMAAm double-network gel on chondrogenic differentiation of mouse C3H10T1/2 cells: in vitro experimental study.
abstract: BACKGROUND
  Recently, several animal studies have found that spontaneous hyaline cartilage regeneration can be induced in vivo within a large osteochondral defect by implanting a synthetic double-network (DN) hydrogel, which is composed of poly-(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) and poly-(N,N'-dimethyl acrylamide) (PDMAAm), at the bottom of the defect. However, the effect of hydrogel on hyaline cartilage regeneration remains unexplained. The purpose of this study was to investigate the chondrogenic differentiation of C3H10T1/2 cells on PAMPS/PDMAAm DN gel.
  
  
  METHODS
  C3H10T1/2 cells of 1.0 × 105 were cultured on PAMPS/PDMAAm DN gel in polystyrene tissue culture dishes or directly on polystyrene tissue culture dishes. We compared cultured cells on PAMPS/PDMAAm DN gel with those on polystyrene dishes by morphology using phase-contrast microscopy, mRNA expression of aggrecan, type I collagen, type II collagen, Sox 9 and osteocalcin using real-time RT-PCR, and local expression of type II collagen using immunocytochemistry.
  
  
  RESULTS
  C3H10T1/2 cells cultured on the PAMPS/PDMAAm DN gels formed focal adhesions, aggregated rapidly and developed into large nodules within 7 days, while the cells cultured on the polystyrene surface did not. The mRNA levels of aggrecan, type I collagen, type II collagen, Sox 9 and osteocalcin were significantly greater in cells cultured on the PAMPS/PDMAAm DN gel than in those cultured on polystyrene dishes. In addition, C3H10T1/2 cells cultured on PAMPS/PDMAAm DN gel expressed more type II collagen at the protein level when compared with cells cultured on polystyrene dishes.
  
  
  CONCLUSIONS
  The present study showed that PAMPS/PDMAAm DN gel enhanced chondrogenesis of C3H10T1/2 cells, which are functionally similar to mesenchymal stem cells. This suggests that mesenchymal stem cells from the bone marrow contribute to spontaneous hyaline cartilage regeneration in vivo in large osteochondral defects after implantation of PAMPS/PDMAAm DN gels.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Inagaki
authors.forename: Nobuto
authors.initials: N
authors.lastname: Kitamura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kurokawa
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Jian P
authors.initials: JP
authors.lastname: Gong
authors.forename: Kazunori
authors.initials: K
authors.lastname: Yasuda
authors.affiliation: Department of Sports Medicine and Joint Surgery, Graduate School of Medicine, Hokkaido University, Kita-15 Nishi-7, Sapporo 060-8638, Japan. tohyama@med.hokudai.ac.jp.
authors.forename: Harukazu
authors.initials: H
authors.lastname: Tohyama
mesh_terms: D000178:Acrylamides / Q000494:pharmacology*; D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D002460:Cell Line; D020219:Chondrogenesis / Q000187:drug effects / Q000502:physiology*; D005782:Gels; D051379:Mice; D008809:Mice, Inbred C3H; D011108:Polymers / Q000494:pharmacology*; D013451:Sulfonic Acids / Q000494:pharmacology*
chemical_list: D000178:Acrylamides; D005782:Gels; D011108:Polymers; D013451:Sulfonic Acids; C429790:poly(N,N-dimethylacrylamide); C077118:poly(2-acrylamido-2-methyl-1-propanesulfonic acid)