3D printing of human ear pinna using cartilage specific ink

Abstract

Biofabrication of a complex structure such as ear pinna is not precise with currently available techniques. Auricular deformities (e.g. microtia) can cause physical, social as well as psychological impacts on a patient’s wellbeing. Currently available surgical techniques and transplantation methods have many limitations that can be overcome with the help of 3D bioprinting technology. Printable bioink enriched with cartilage-specific extracellular matrix (ECM) synthesis was done by digesting goat ear pinna cartilage and polymerized by adding polyvinyl alcohol and gelatine. Rheological analysis and Fourier-transform infrared spectroscopy were used for the characterization of bioink to get desired viscosity and polymerization. Human ear pinna was printed using extrusion method and computer-aided design, stereolithography software which facilitated the automated printing in relatively less time without continuous monitoring. Thermal degradation of pinna was checked by thermal gravimetric analysis. Biodegradability and swelling of ear pinna were observed for understanding the nature of pinna and the impact of external factors. Reconstructed pinna’s biocompatibility was proved by in ovo and in vivo studies. The occurrence of angiogenesis in the grafted ear manifested the capacity of proliferation and engraftment of cartilage cells. Histology and SEM analysis revealed the recellularization and the synthesis of ECM components such as glycosaminoglycan and collagen in transplanted 3D printed ear pinna. The expression of CD90+ which indicated newly synthesized cartilage in the transplanted 3D printed ear pinna. The absence expression of CD14+ also indicated acceptance of xenogenic transplanted 3D printed ear pinna. Transplantation of 3D ear pinna was successful in an animal model and can be utilized as tissue engineered ear bank.

Bioprinting and regeneration of auricular cartilage using a bioactive bioink based on microporous photocrosslinkable acellular cartilage matrix

“…Despite such promising advances, the present ACM-based biomaterials have insufficient constructability and mechanical stability, which risks hampering practical applications for fabricating the desired 3D constructs [ 25 , 49 ]. To address this problem, ACM was modified with MA to prepare a methacrylate-modified ACM with rapid photocrosslinking properties.…”

“…Therefore, the integration of hydrogels and bioprinting technology may be the key breakthrough to address the above problems. Nevertheless, the common hydrogels used to construct auricle equivalents have the following deficiencies: (1) the single components of conventional hydrogels have difficulty accurately mimicking the cartilage-specific microenvironment [ 23 ]; (2) the dense texture of the solidified hydrogels hinders the exchange of nutrients and affects the formation of internal cartilage tissue [ 24 ]; and (3) insufficient mechanical stability of hydrogels is not enough to maintain the fidelity of 3D morphology [ 25 ].…”

Bioprinted dermis with human adipose tissue‐derived microvascular fragments promotes wound healing

“…However, the application of tissue engineering in clinical settings is limited by poor vascularization (Rehman et al, 2019;Tarassoli et al, 2018). Vascular fragments have long been considered as the units of vascular With the development of 3D bioprinting technologies, several biological materials have been combined to produce bioinks in addition to natural and synthetic biological materials (Bhamare et al, 2021). An ideal bioink must possess the biological characteristics and mechanical properties of the target tissue (Gungor-Ozkerim et al, 2018).…”

Human-engineered auricular reconstruction (hEAR) by 3D-printed molding with human-derived auricular and costal chondrocytes and adipose-derived mesenchymal stem cells

“…To increase cartilage formation, decellularized extracellular matrix bioinks were used. Bhamare et al digested goat auricular cartilage polymerized with polyvinyl alcohol and gelatine and used it as a bioink for extrusion printing by computer-aided design [25]. In another study, porcine auricular cartilage was methacrylated to form a photo-cross-linkable hydrogel and suspended with chondrocytes to form a bioink [26].…”