Autologous diced cartilage, while biocompatible and easy to shape, is limited in clinical application due to its high adsorption rate and challenges in establishing timely and effective neovascularization postsurgery. In this study, the authors produced SVF cell sheets from adipose-derived stromal vascular fraction (SVF) through enzymatic digestion, employing a temperature-sensitive culture system. Our in vivo and in vitro experiments validated that SVF cell sheets, when wrapped around granular cartilage, exhibited a notable promotion of cartilage regeneration and mitigated granular cartilage adsorption in a rabbit diced cartilage graft model. Our findings demonstrate that SVF cell sheets facilitated effective neovascularization and timely cartilage block formation by secreting VEGF and Ang-1 while also suppressing the expression of pyroptotic proteins like NLRP3, Caspase1, and GSDMD. As a biofilm, derived from a multicellular source, SVF cell sheets can replace perichondrium and promote the expression of proangiogenic growth factors Ang-1 and VEGF, thereby promoting local microvascular regeneration, reducing chondrocyte pyroptosis, and promoting the formation of cartilage blocks. This strategy provides a potential new method for autologous cartilage grafting, which will help solve the dilemma of limited sources of cartilage tissue in clinical practice and provide natural autologous cartilage filling materials for the treatment of craniofacial defects.

Microtia has severe physical and psychological impacts on patients, and auricular reconstruction offers improved esthetics and function, alleviating psychological issues. Microtia is a congenital disease caused by a multifactorial interaction of environmental and genetic factors, with complex clinical manifestations. Classification assessment aids in determining treatment strategies. Auricular reconstruction is the primary treatment for severe microtia, focusing on the selection of auricular scaffold materials, the construction of auricular morphology, and skin and soft tissue scaffold coverage. Autologous rib cartilage and synthetic materials are both used as scaffold materials for auricular reconstruction, each with advantages and disadvantages. Methods for achieving skin and soft tissue scaffold coverage have been developed to include nonexpansion and expansion techniques. In recent years, the application of digital auxiliary technology such as finite element analysis has helped optimize surgical outcomes and reduce complications. Tissue-engineered cartilage scaffolds and 3-dimensional bioprinting technology have rapidly advanced in the field of ear reconstruction. This article discusses the prevalence and classification of microtia, the selection of auricular scaffolds, the evolution of surgical methods, and the current applications of digital auxiliary technology in ear reconstruction, with the aim of providing clinical physicians with a reference for individualized ear reconstruction surgery. The focus of this work is on the current applications and challenges of tissue engineering and 3-dimensional bioprinting technology in the field of ear reconstruction, as well as future prospects.

OBJECTIVES:This study explored the effect of adipose-derived stromal vascular fractions (SVFs) on angiogenesis in injected autologous diced cartilage.METHODS:Stromal vascular fractions were extracted by enzymatic digestion. Cartilage grafts were harvested from 1 side of the auricular cartilage of New Zealand rabbit and then diced to a size of 1.0 mm3. The grafts were divided into 2 groups. The control group was diced cartilage mixed with culture medium, and the experimental group was diced cartilage mixed with SVFs. The 2 groups of composite grafts were subcutaneously implanted on both sides of the back of each rabbit. After 4, 12 and 24 weeks, the tissue structure, number of blood vessels, and angiogenic factors in the grafts were observed.RESULTS:The SVFs conformed to the current standard of the biological evaluation. Under an inverted microscope, the number of layers of chondrocytes in the experimental group was higher than that in the control group at 4 weeks. A small number of inflammatory cells and blood vessels were observed around the cartilage grafts. At 12 and 24 weeks, the volume of tissue was increased gradually by general observation. And a large number of chondrocytes were observed microscopically, whereas the number of inflammatory cells decreased. And meanwhile additional new blood vessels were observed. Immunohistochemical analysis of CD31 showed that the number of capillaries in the control group was significantly lower than that in the experimental group at 4, 12 and 24 weeks. Further, the expression of Hypoxia inducible factor-1 (HIF-1) and vascular endothelial growth factor (VEGF) mRNA and protein were measured by RT-PCR and Western bloting, respectively. The results showed that the mRNA expression of VEGF and HIF-1α in the experimental group was increased. The mRNA level remained higher than that of the control group at 24 weeks (P < 0.05). And the relative expression levels of VEGF and HIF-1α protein in the experimental group were higher than those in the control group at 4, 12 and 24 weeks (P < 0.05).CONCLUSION:Autologous diced cartilage mixed with adipose-derived SVFs can promote angiogenesis when transplanted by injection. Further research showed that SVFs could increase the expression levels of VEGF and HIF-1α in the grafts, which may be part of the mechanism that SVFs promoted the angiogenesis of diced cartilage.

细胞膜片技术是一种应用不同方式将细胞制备成片状的技术,该技术保留了大量的细胞外基质,在骨与软骨组织的修复与再生过程中起到了重要作用.本文将温度敏感培养法、表面修饰法、不需要任何表面修饰的制备细胞膜片的3种方式,以及细胞膜片技术在骨、软骨修复与再生领域中的研究进展及发展前景进行综述.

OBJECTIVE:This study aims to investigate the effect of Bacillus subtilis WB800N on diabetic wounds. METHODS:Haematoxylin & eosin (H&E) staining was used to observe the healing of skin wounds. Collagen deposition was assessed by Masson staining. Western blotting and qRT-PCR were used to detect vascular endothelial-related factors (VWF), CD31, TLR2, NLRP3, ASC and Caspase-1 expression. 16S rDNA sequencing detected microbiota distribution. The concentrations of IL-1β and IL-37 were measured by ELISA. Apoptosis was measured by the TUNEL assay. RESULTS:Compared with the control group, wound healing was delayed in diabetic mice. The wound area in the Bacillus subtilis group decreased more significantly than the diabetic wound group. H&E staining showed that Bacillus subtilis WB800N promoted wound healing and increased re-epithelialization. Masson staining showed that Bacillus subtilis WB800N increased collagen deposition in mice with diabetic wounds. Bacillus subtilis WB800N upregulated VWF and CD31 protein expression in diabetic wounds mice. The 16S rDNA results showed that Bacillus subtilis WB800N reduced the diversity of the gut microbiota of diabetic wounds mice and regulated the microbial composition. At the genus level, Bacillus subtilis WB800N reduced the relative abundance of Muribaculaceae and CG - 005 in diabetic wounds mice, whilst increasing the relative abundance of Lactobacillus. Bacillus subtilis WB800N increased the expression of TLR2, NLRP3, ASC and Caspase-1. Bacillus subtilis WB800N increased the concentrations of IL-1β and IL-37 in serum. Bacillus subtilis WB800N upregulated cell apoptosis. The TLR2 antagonist Sparstolonin B (SsnB) reduced the expression of TLR2, NLRP3, ASC, Caspase-1, IL-1β and IL-37 and the apoptosis in diabetic wounds mice, whilst the combined intervention of Bacillus subtilis and SsnB reversed the effect of SsnB treatment alone. CONCLUSION:Bacillus subtilis WB800N alleviated diabetic wound healing by regulating gut microbiota homeostasis and TLR2. SIGNIFICANCE AND IMPACT OF RESEARCH:Our findings might provide potential therapeutic targets for diabetic wounds.