Fabrication and evaluation of an optimized xenogenic decellularized costal cartilage graft:preclinical studies of a novel biocompatible prosthesis for rhinoplasty

On account of the poor biocompatibility of synthetic prosthesis,millions of rhinoplasty recipients have been forced to choose autologous costal cartilage as grafts,which suffer from limited availability,morbidity at the donor site and prolonged operation time.Here,as a promising alternative to autologous costal cartilage,we developed a novel xenogeneic costal cartilage and explored its feasibility as a rhinoplasty graft for the first time.Adopting an improved decellularization protocol,in which the ionic detergent was substituted by trypsin,the resulting decellularized graft was confirmed to preserve more structural components and better mechanics,and eliminate cellular components effectively.The in vitro and in vivo compatibility experiments demonstrated that the decellularized graft showed excellent biocompatibility and biosecurity.Additionally,the functionality assessment of rhinoplasty was performed in a rabbit model,and the condition of grafts after implantation was comprehensively evaluated.The optimized graft exhibited better capacity to reduce the degradation rate and maintain the morphology,in comparison to the decellularized costal cartilage prepared by conventional protocol.These findings indicate that this optimized graft derived from decellularized xenogeneic costal cartilage provides a new prospective for future investigations of rhinoplasty prosthesis and has great potential for clinical application.

Gold nanoclusters conjugated berberine reduce inflammation and alleviate neuronal apoptosis by mediating M2 polarization for spinal cord injury repair

Spinal cord injury(SCI)leads to nerve cell apoptosis and loss of motor function.Herein,excessive activation of the M1 phenotype macrophages/microglia is found to be the main reason for the poor prognosis of SCI,but the selective activation phenotype(M2)macrophages/microglia facilitates the recovery of SCI.Thereafter,we used gold nanoclusters loaded berberine(BRB-AuNCs)to reduce inflammation by inhibiting the activation of M1 phenotype macrophages/microglia,which simultaneously inhibited neuronal apoptosis after SCI.In vitro and in vivo experiments showed that BRB-AuNCs reduced M1 protein marker CD86,increased M2 protein marker CD206,reduced inflammation and apoptotic cytokines(IL-1β,IL-6,TNF-α,Cleaved Caspase-3 and Bax).These results indicate that BRB-AuNCs have excellent anti-inflammatory and anti-apoptotic effects by inducing the polarization of macrophages/microglia from M1 phenotype to M2 phenotype.Thereafter,the motor functions of SCI rats were significantly improved after treatment with BRB-AuNCs.This work not only provides a new way for the treatment of SCI but also broadens BRB utilization strategies.