title: [Formation of the allogeneic tissue engineered cartilage using injectable biomaterial].
abstract: OBJECTIVE
  To study the feasibility of the formation of allogeneic tissue-engineered cartilage of certain shape in immunocompetent animal using the injectable biomaterial.
  
  
  METHODS
  Fresh newborn rabbits' articular cartilages were obtained under sterile condition (< 6 hours after death) and incubated in the sterile 0.3% type II collagenase solution. After digestion of 8 to 12 hours, the solution was filtered through a 150 micron nylon mesh and centrifuged, then the chondrocytes were washed twice with phosphate buffered saline (PBS) and mixed with the biomaterial to create a final cell density of 5 x 10(7)/ml. The cell-biomaterial admixture was injected into rabbits subcutaneously 0.3 ml each point while we drew the needle back in order to form the neocartilage in the shape of cudgel, and the control groups were injected with only the biomaterial or the suspension of chondrocytes with the density of 5 x 10(7)/ml. After 4, 6, 8 and 12 weeks, the neocartilages were harvested to analyze.
  
  
  RESULTS
  The new nodes could be touched subcutaneously after 2 weeks. In the sections of the samples harvested after 4 weeks, it was found that the matrix secreted and the collagen formed. After 6 weeks and later than that, the neocartilages were mature and the biomaterial was almost completely degraded. The cudgel-shaped samples of neocartilage could be formed by injection. In the experiment group, there was no obvious immune rejection response. On the contrary, there were no neocartilage formed in the control group.
  
  
  CONCLUSIONS
  The injectable biomaterial is a relatively ideal biomaterial for tissue engineering, and it is feasible to form allogeneic tissue engineered cartilage of certain shape by injection in an immunocompetent animal.
authors.affiliation: Department of Otolaryngology, Tangdu Hospital, Fourth Military Medical University, Xi'an Shanxi, P. R. China 710038.
authors.forename: J S
authors.initials: JS
authors.lastname: Luo
authors.forename: G Z
authors.initials: GZ
authors.lastname: Li
authors.forename: P C
authors.initials: PC
authors.lastname: Cui
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D002356:Cartilage / Q000166:cytology*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000502:physiology*; D005240:Feasibility Studies; D007279:Injections, Subcutaneous; D011817:Rabbits; D023822:Tissue Engineering; D014184:Transplantation, Homologous
chemical_list: D001672:Biocompatible Materials