Decellularized tissue engineering scaffolds appear to have the properties of similar structure and mechanical characteristics to native tissues，good biocompatibility，suitability for cell adhesion，growth and angiogenesis induction，and non-immunogenicity. Genipin has anti-inflammatory，antithrombotic and antioxidative features which can considerably suppress vascular and endothelial inflammatory activation，increase mechanical strength of biological scaffolds，inhibit inflammatory response and decrease degradation rate of biological scaffolds. By cross-linking with decellularized matrices，Genipin can further improve corresponding performance of tissue engineering matrices，which is very helpful to promote the application of tissue engineering into clinical practice of cardiothoracic surgery. This review focuses on recent research process and possible prospects of Genipin cross-linking in tissue engineering in the field of cardiothoracic surgery.
ObjectiveTo investigate the biocompatibility and immunogenicity of the tracheal matrix decellularized by sodium perchlorate (NaClO4).MethodsBone marrow mesenchymal stem cells (BMSCs) were divided from 2-month-old New Zealand white rabbits. The trachea of 6-month-old New Zealand white rabbits were trimmed to a length of 1.5 cm and randomly divided into control group (group A1, n=5, just stripped the loose connective tissue outside the trachea) and experimental group (group B1, n=5, decellularized by improved NaClO4 immersion method). The cytotoxicity of the scaffold leaching solution was detected by MTT assay, and the major histocompatibility complex (MHC) expression was detected by immunohistochemical method. The 4th generation of BMSCs were seeded onto the scaffold of 2 groups, and the cell activity around the material was observed by inverted microscope after Giemsa staining at 48 hours, while the cells states on the scaffold were observed at 7 and 14 days after culturing by scanning electron microscope. Another 10 6-month-old New Zealand white rabbits were randomly divided into control group (group A2, n=5) and experimental group (group B2, n=5), which implanted the native trachea and decellularized tracheal matrix into the subcutaneous sac of the back neck, respectively. The serum immunoglobulin IgM and IgG contents were analysed at 5, 10, 15, 20, 25, and 30 days after operation, and HE staining observation was performed at 30 days after operation.ResultsMTT assay showed that the proliferation activity of BMSCs cultured in the leach liquor of group B1 was well, showing no significant difference when compared with group A1 and negative control group with pure culture medium (P>0.05). The immunohistochemical staining showed that the decellularized process could significantly reducing the antigenicity of matrix materials. Giemsa staining showed that BMSCs grew well around the two tracheal matrixs (groups A1 and B1) in vitro. Scanning electron microscope observation showed that the cells were attached to the outer wall of the tracheal material in group A1, which present a flat, round, oval shaped, tightly arranged cells and cluster distribution; and in group B1, the cells formed a single lamellar sheet cover the outer wall of the tracheal material, whose morphology was similar to that in group A1, and the growth trend was better. In vivo experimental results showed that the rejection of group B2 was lower than that of group A2. The contens of IgM and IgG in group A2 were significantly higher than those in group B2 at each time point after operation (P<0.05). HE staining showed no signs of rejection, macrophagocyte, or lymphocyte infiltration occurred, and the collagen fibers maintained their integrity in group B2.ConclusionThe decellularized matrix treated by NaClO4 has a fine biocompatibility, while its immunogenicity decreased, and it is suitable for the scaffold material for constructing of tissue engineered trachea.