In vivo implantation of tissue-engineered human nasal septal neocartilage constructs: a pilot study.
OBJECTIVE
To determine the in vivo biocompatibility of septal neocartilage constructs developed in vitro by an alginate intermediate step.


METHODS
Prospective, animal model.


METHODS
Research laboratory.


METHODS
A murine model was used to examine the maturation of neocartilage constructs in vivo. Chondrocytes collected from patients undergoing septoplasty were expanded in monolayer and suspended in alginate beads for 3-dimensional culture in media containing human serum and growth factors. After in vitro incubation for 5 weeks, the constructs were implanted in the dorsum of athymic mice for 30 and 60 days (n = 9). After the mice were sacrificed, the constructs were recovered for assessment of their morphological, histochemical, biochemical, and biomechanical properties.


RESULTS
The mice survived and tolerated the implants well. Infection and extrusion were not observed. Neocartilage constructs maintained their general shape and size and demonstrated cell viability after implantation. The implanted constructs were firm and opaque, sharing closer semblance to native septal tissue relative to the gelatinous, translucent preimplant constructs. Histochemical staining with hematoxylin and eosin (H&E) revealed that the constructs exhibited distinct morphologies characteristic of native tissue, which were not observed in preimplant constructs. DNA and type II collagen increased with duration of implantation, whereas type I collagen and glycoaminoglycans (GAG) decreased. Mechanical testing of a 60-day implanted construct demonstrated characteristics similar to native human septal cartilage.


CONCLUSIONS
Neocartilage constructs are viable in an in vivo murine model. The histologic, biochemical, and biomechanical features of implanted constructs closely resemble native septal tissue when compared with preimplant constructs.
Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, California, USA.
Angela A
AA
Chang
Marsha S
MS
Reuther
Kristen K
KK
Briggs
Barbara L
BL
Schumacher
Gregory M
GM
Williams
Maripat
M
Corr
Robert L
RL
Sah
Deborah
D
Watson
D000818:Animals; D004195:Disease Models, Animal; D005500:Follow-Up Studies; D006085:Graft Survival; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D055171:Nasal Cartilages / Q000637:transplantation*; D009300:Nasal Septum / Q000637:transplantation*; D009667:Nose Deformities, Acquired / Q000601:surgery*; D010865:Pilot Projects; D011446:Prospective Studies; D023822:Tissue Engineering; D016896:Treatment Outcome