Different Ratios of Bone Marrow Mesenchymal Stem Cells and Chondrocytes Used in Tissue-Engineered Cartilage and Its Application for Human Ear-Shaped Substitutes in vitro

Abstract

The application of chondrocyte-based cartilage tissue engineering is limited because of the lack of autologous cartilage sources and chondrocyte dedifferentiation after in vitro expansion. Coculture of bone marrow mesenchymal stem cells (BMSCs) and chondrocytes has been a promising strategy for cartilage engineering as chondrocytes can provide a chondrogenic environment for BMSCs. However, there are no systematic comparison studies for engineered cartilage constructed using different mixing ratios of BMSCs and chondrocytes, and the most effective mixing ratio with the lowest number of chondrocytes is unknown. Here, we set a gradient of mixing ratios of BMSCs to chondrocytes for an in vitro coculture system and compared the shape retention and quality of the engineered cartilage using macroscopic and histological assays, glycosaminoglycan content assessment and immunohistochemical staining of type II collagen, biomechanical evaluation and hypertrophy-related gene expression analysis. The results showed that at least 30% chondrocytes were required to generate cartilage tissue with satisfactory shape and quality. Therefore, we preliminarily assessed the feasibility of engineering a human ear-shaped substitute using a coculture system with a 7:3 ratio of BMSCs to chondrocytes. After 8 weeks of in vitro culture, the precise architecture of the human ear-shaped construct was well maintained with the typical cartilaginous composition confirmed by histological assays.

Chondrocytes from congenital microtia possess an inferior capacity for in vivo cartilage regeneration to healthy ear chondrocytes

“…Tissue engineering has provided a promising perspective in the field of auricular reconstruction (Shieh et al ., ). The feasibility and efficacy to construct a cartilaginous tissue in the shape of human ear using tissue engineering technique have been successfully demonstrated by several groups (Kang et al ., ; Liu et al ., ; Pomerantseva et al . ; Zhou et al ., ).…”

“…Tissue engineering has provided a promising perspective in the field of auricular reconstruction (Shieh et al, 2004). The feasibility and efficacy to construct a cartilaginous tissue in the shape of human ear using tissue engineering technique have been successfully demonstrated by several groups (Kang et al, 2013;Liu et al, 2010;Pomerantseva et al 2016;Zhou et al, 2011). The seed cells applied in previous studies included physiological chondrocytes derived from auricular, articular, nasal septum, and costal cartilage sources (Isogai et al, 2006).…”

Silk Fibroin Scaffold-Based 3D Co-Culture Model for Modulation of Chondrogenesis without Hypertrophy via Reciprocal Cross-talk and Paracrine Signaling

“…31 Researchers have also demonstrated that minimum 20−30% of chondrocytes are required in co-culture ratios in order to produce cartilage tissue with good shape retention and for induction of stem cell differentiation. 32 Herein, our ultimate goal was to achieve equal or better chondrogenesis than chondrocytes alone while minimizing the load of chondrocytes, which are highly differentiated cells and difficult to isolate in desired numbers. Therefore, these abovementioned ratios were utilized in our study for reducing the chondrocyte number by replacement with the alternative cell source, MSCs, with the aim to achieve equal or even better chondrogenesis than chondrocytes.…”

Generation of Ear Cartilage for Auricular Reconstruction

“…To address the issue of terminal ossification of MSCs, the co-culture of MSCs with mature chondrocytes has been investigated and found to be effective in generating phenotypically stable cartilage in the subcutaneous implantation site for the regenerated auricle (Zhang et al 2014). Besides phenotype maintenance, co-culturing can effectively reduce the quantity demand for chondrocytes, which are limited in supply, while exert the merit of MSCs which are more readily available (Kang et al 2013;Zhang et al 2014). Kang et al found that a co-culture arrangement of 30% chondrocytes and 70% BMSCs could generate ear-shaped cartilage in vitro (Kang et al 2013).…”

“…Besides phenotype maintenance, co-culturing can effectively reduce the quantity demand for chondrocytes, which are limited in supply, while exert the merit of MSCs which are more readily available (Kang et al 2013;Zhang et al 2014). Kang et al found that a co-culture arrangement of 30% chondrocytes and 70% BMSCs could generate ear-shaped cartilage in vitro (Kang et al 2013). Zhang et al reported the generation of stable subcutaneous human earshaped cartilage engineered through co-culturing of a 30% human microtia chondrocytes with 70% human BMSCs in a nude mouse model (Zhang et al 2014).…”