title: Evaluation of chondrocytes expression embedded in thermoresponsive poly(amino acid)s with sol-gel transition.
abstract: Poly(N-substituted alpha/beta-asparagine) was evaluated as a thermoresponsible and an injectable scaffold for cartilage regeneration. Solutions of this polymer are liquid state below 25 degrees C and nonfluid hydrogel above 35 degrees C, allowing an aqueous solution containing cells at room temperature to form a hydrogel with encapsulated cells at physiological body temperature. Chondrocytes were isolated from joint of 4-week-old Japanese white rabbits, dispersed within the thermoresponsive polymer solution and maintained for up to 72 hours in vitro. The polymer solutions demonstrated concentration-dependent inhibitory effect on chondrocytes multiplication. After the three-day cultivation, the survival rate of the chondrocytes fell into a 70~90% ranges among all the tested polymer concentrations. The morphology studies showed that there were some physical and/or chemical stress leading cells to necrosis and some extent apoptosis. Some physical and/or chemical stress may be applied, and over 70% of the chondrocytes could survive through the stress, suggesting that some phenotype could have been selected from the heterogeneous mixture of chondrocytes.
authors.affiliation: Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Shang-Kai
authors.initials: SK
authors.lastname: Chueh
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Tachibana
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Uyama
authors.forename: Shiro
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Naohide
authors.initials: N
authors.lastname: Tomita
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D001704:Biopolymers / Q000737:chemistry*; D002470:Cell Survival; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000637:transplantation; D005240:Feasibility Studies; D048091:Guided Tissue Regeneration / Q000379:methods*; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008422:Materials Testing; D044367:Phase Transition; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D000596:Amino Acids; D001704:Biopolymers