In Vivo Implantation of Tissue‐Engineered Human Nasal Septal Neocartilage Constructs

Abstract

Objective To determine the in vivo biocompatibility of septal neocartilage constructs developed in vitro by an alginate intermediate step. Study Design Prospective, animal model. Setting Research laboratory. Subjects and 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 three-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 pre-implant 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 pre-implant 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 to pre-implant constructs.

New application of three‐dimensional printing biomaterial in nasal reconstruction

“…Autologous cartilage is considered to be ideal for all implant types in nasal surgery but is limited by the finite amount of available tissue. Additionally, the acquisition of cartilage is associated with various morbidity or mortality, and its use is associated with an unpredictable degree of absorption and inflammation . Therefore, the development of alloplastic materials provides a new alternative to autologous implant.…”

10.4172/2324-8785.1000172

“…The sections were placed on poly-L lysine coated slides (Polysciences Inc., Warrington, PA) and allowed to dry overnight. Staining with H&E was performed as previously described [17]. For histochemical localization of GAG, slides from each sample group were stained with 0.1% alcian blue in buffer (0.4 M MgCl 2 , 0.025 M Sodium acetate, 2.5% glutaraldehyde, pH 5.6) overnight, and destained with 3% acetic acid until clear [18].…”

“…Moreover, this can be further limited by trauma, congenital deformities, or iatrogenic septal defects. Previous studies have successfully produced tissue engineered autologous neocartilage that may eventually be used for reconstructive surgery [5-7]. …”

5 Fundamentals of Tissue Engineering

“…5.5). 76 A clear construct maturation process was reported with post-implant constructs having acquired a histologic pattern typical of native cartilage, increasing collagen to GAG ratio, and increasing mechanical strength with time. The dynamic modulus and failure strain of the 60-day implanted cartilage constructs were similar to that of native human nasal septal cartilage.…”