Nasal deformities due to various causes affect the aesthetics and use of the nose, in which case rhinoplasty is necessary. However, the lack of cartilage for grafting has been a major problem and tissue engineering seems to be a promising solution. 3D bioprinting has become one of the most advanced tissue engineering methods. To construct ideal cartilage, bio-ink, seed cells, growth factors and other methods to promote chondrogenesis should be considered and weighed carefully. With continuous progress in the field, bio-ink choices are becoming increasingly abundant, from a single hydrogel to a combination of hydrogels with various characteristics, and more 3D bioprinting methods are also emerging. Adipose-derived stem cells (ADSCs) have become one of the most popular seed cells in cartilage 3D bioprinting, owing to their abundance, excellent proliferative potential, minimal morbidity during harvest and lack of ethical considerations limitations. In addition, the coculture of ADSCs and chondrocytes is commonly used to achieve better chondrogenesis. To promote chondrogenic differentiation of ADSCs and construct ideal highly bionic tissue-engineered cartilage, researchers have used a variety of methods, including adding appropriate growth factors, applying biomechanical stimuli and reducing oxygen tension. According to the process and sequence of cartilage 3D bioprinting, this review summarizes and discusses the selection of hydrogel and seed cells (centered on ADSCs), the design of printing, and methods for inducing the chondrogenesis of ADSCs.
| INTRODUCTIONTrauma, burn, tumour, surgery, or congenital malformation of nasal cartilage may compromise a nasal deformity or lead to nasal airway dysfunction, affecting the aesthetics and utility of the nose. 1 Rhinoplasty usually requires trimming of nasal cartilage and implantation of grafts. Therefore, finding the most suitable and compatible cartilage graft material is essential. Ideally, the engineered cartilage graft should have properties to meet the clinical needs of the recipient site, including being able to withstand the external forces in the nasal reconstructive environment, biocompatible, and biologically active to support and promote tissue integration and healing. Besides, it should be readily available or easy to access without contributing to donor site morbidity. Moreover, from a surgical point of view, the graft material needs to be big enough in the case of intraoperative trimming to meet the needs of patients.Chong Zhang and Guanhuier Wang contributed equally to this work.
