Activating the healing process: three-dimensional culture of stem cells in Matrigel for tissue repair.

BACKGROUND: To establish a strategy for stem cell-related tissue regeneration therapy, human gingival mesenchymal stem cells (hGMSCs) were loaded with three-dimensional (3D) bioengineered Matrigel matrix scaffolds in high-cell density microtissues to promote local tissue restoration. METHODS: The biological performance and stemness of hGMSCs under 3D culture conditions were investigated by viability and multidirectional differentiation analyses. A Sprague‒Dawley (SD) rat full-thickness buccal mucosa wound model was established, and hGMSCs/Matrigel were injected into the submucosa of the wound. Autologous stem cell proliferation and wound repair in local tissue were assessed by histomorphometry and immunohistochemical staining. RESULTS: Three-dimensional suspension culture can provide a more natural environment for extensions and contacts between hGMSCs, and the viability and adipogenic differentiation capacity of hGMSCs were significantly enhanced. An animal study showed that hGMSCs/Matrigel significantly accelerated soft tissue repair by promoting autologous stem cell proliferation and enhancing the generation of collagen fibers in local tissue. CONCLUSION: Three-dimensional cell culture with hydrogel scaffolds, such as Matrigel, can effectively improve the biological function and maintain the stemness of stem cells. The therapeutic efficacy of hGMSCs/Matrigel was confirmed, as these cells could effectively stimulate soft tissue repair to promote the healing process by activating the host microenvironment and autologous stem cells.

Harnessing Healing Power: A Comprehensive Review on Platelet-Rich Plasma in Compound Fracture Care.

This comprehensive review explores the applications of platelet-rich plasma (PRP) in the context of compound fracture care, providing a thorough examination of its biological mechanisms, preparation techniques, and clinical implications. The analysis highlights PRP's potential in accelerating bone healing, enhancing soft tissue repair, reducing inflammation and infection risks, and managing pain during fracture recovery. The review underscores the importance of ethical and regulatory considerations in integrating PRP into orthopaedic practice, emphasising informed consent, transparent patient communication, and ongoing monitoring of ethical concerns. Looking ahead, the implications for the future of compound fracture care suggest a transformative shift with the potential for personalised medicine approaches and emerging technologies. However, the conclusion calls for a balanced perspective, acknowledging the promising applications of PRP while emphasising the need for responsible and ethical use. The collaborative efforts of healthcare professionals, researchers, and regulatory bodies are crucial in navigating this evolving landscape and harnessing the healing power of PRP to redefine orthopaedic care for individuals with compound fractures.

Influence of adipose tissue and its derivative on wound repair and vascularization / 中国组织工程研究

BACKGROUND:Vascularization is essential for wound healing and functional recovery during soft tissue repair.Adipose tissue is believed to be the body's largest source of stem cells,and a number of different fat complexes have been developed for research and treatment.Its ability to promote angiogenesis and soft tissue repair has been extensively studied. OBJECTIVE:To review the progress of vascularization in soft tissue repair,and to summarize the preparation methods of adipose tissue and its derivative and their applications in vascularization and soft tissue repair.It is proven that adipose tissue and its derivative have excellent research value and clinical application prospects in vascular and soft tissue engineering. METHODS:PubMed,Web of Science and CNKI databases were used to search the related articles published from January 2010 to February 2023.The search terms were"soft tissue repair,wound healing,vascularization,angiogenesis,adipose tissue,stromal vascular fraction,adipose tissue-derived microvascular fragment,nanofat,adipose extracellular matrix/stromal vascular fraction gel"in Chinese and English.A small number of old classic literature was also included.An initial screening was performed by reading the titles and abstracts to exclude literature that was not relevant to the topic of the article,and 69 papers were finally included for the analysis of the result. RESULTS AND CONCLUSION:(1)Wound healing is an important physiological process,which mainly occurs when tissue is damaged,such as injury,surgery,burn,tumor,infection and vascular disease caused by tissue damage and defects.(2)Adequate vascularization of the wound site is essential for tissue repair,reconstruction of local homeostasis and functional recovery.(3)Adipose tissue is believed to be the body's largest pool of stem cells and a number of different fat components have been used for research and treatment.(4)Due to its inherent composition and preparation advantages,adipose tissue will continue to play an important role in tissue engineering research and therapy.

Potential and advantages of metal organic frameworks-based hydrogel materials for repairing soft and hard tissues / 中国组织工程研究

BACKGROUND:Due to the mechanical properties,unstable drug release,single function and other problems of pure hydrogel materials,in recent years,researchers have prepared a variety of metal organic frameworks-based hydrogel materials by introducing metal organic frameworks into hydrogel,and showed great potential in the field of soft and hard tissue regeneration. OBJECTIVE:To classify the metal organic frameworks-based hydrogel materials based on how metal organic frameworks enhance the properties of hydrogel and further summarize its recent research in the field of soft and hard tissue regeneration,in order to provide ideas and theoretical supports for the subsequent in-depth research on synthesis mechanism and clinical application of the composite material. METHODS:Using"metal organic frameworks,hydrogels,tissue engineering,tissue,bone regeneration,bone,wound"as English and Chinese search terms,we searched Web of Science,PubMed,CNKI,and Wanfang databases.The search period ranged from January 2000 to August 2023.By reading the titles and abstracts,the repetitive studies and unrelated literature of Chinese and English literature were excluded.After the literature quality evaluation,73 articles were included for review. RESULTS AND CONCLUSION:(1)Metal organic frameworks-based hydrogel materials effectively solve the problems of poor mechanical properties,unstable drug release and single function of pure hydrogel.(2)Metal organic frameworks enhance the capacity of repair and regeneration by strengthening the cross-linking of hydrogel,the drug delivery capacity of hydrogel and the multifunction of hydrogel.(3)In terms of hard tissue repair,it has shown good repair effects in animal models of diseases such as bone defects,osteoarthritis,and cartilage defects,suggesting potential application prospects in clinical repair.(4)In terms of soft tissue regeneration,it has the capacities of hemostasis,antibacterial,inflammatory state regulation,oxidative stress state regulation,promoting angiogenesis and other functions,effectively improving the microenvironment of various complex wounds and promoting soft tissue regeneration.(5)Although metal organic frameworks-based hydrogels have many excellent properties,they are still in the initial stage and there are some urgent problems to be solved in the process of clinical transformation,such as the cytotoxicity of metal organic frameworks and large-scale synthesis of metal organic frameworks.(6)With further research,metal organic frameworks-based hydrogels have broad application prospects in the field of soft and hard tissue repair.

Toughening Double-Network Hydrogels by Polyelectrolytes.

The Hoffmeister effect of inorganic salts is verified as a promising way to toughen hydrogels, however, the high concentration of inorganic salts may be accompanied by poor biocompatibility. In this work, it is found that polyelectrolytes can obviously elevate the mechanical performances of hydrogels through the Hoffmeister effect. The introduction of anionic poly(sodium acrylate) into poly(vinyl alcohol) (PVA) hydrogel induces the aggregation and crystallization of the PVA to boost the mechanical properties of the resulting double-network hydrogel: elevation of 73, 64, 28, 135, and 19 times in the tensile strength, compressive strength, Young's modulus, toughness, and fracture energy compared with poly(acrylic acid), respectively. It is noteworthy that the mechanical performances of the hydrogels can be flexibly tuned by the variation of polyelectrolyte concentration, ionization degree, relative hydrophobicity of the ionic component, and polyelectrolyte type in a wide range. This strategy is verified to work for other Hoffmeister-effect-sensitive polymers and polyelectrolytes. Also, the introduction of urea bonds into the polyelectrolyte can further improve the mechanical properties and antiswelling capability of hydrogels. As a biomedical patch, the advanced hydrogel can efficiently inhibit hernia formation and promote the regeneration of soft tissues in an abdominal wall defect model.

Improved suture pullout through genipin-coated sutures in human biceps tendons with spatially confined changes in cell viability.

BACKGROUND: The suture-tendon interface often constitutes the point of failure in tendon suture repair. In the present study, we investigated the mechanical benefit of coating the suture with a cross-linking agent to strengthen the nearby tissue after suture placement in human tendons and we assessed the biological implications regarding tendon cell survival in-vitro. METHODS: Freshly harvested human biceps long head tendons were randomly allocated to control (n = 17) or intervention (n = 19) group. According to the assigned group, either an untreated or a genipin-coated suture was inserted into the tendon. 24 h after suturing, mechanical testing composed of cyclic and ramp-to-failure loading was performed. Additionally, 11 freshly harvested tendons were used for short-term in vitro cell viability assessment in response to genipin-loaded suture placement. These specimens were analyzed in a paired-sample setting as stained histological sections using combined fluorescent/light microscopy. FINDINGS: Tendons stitched with a genipin-coated suture sustained higher forces to failure. Cyclic and ultimate displacement of the tendon-suture construct remained unaltered by the local tissue crosslinking. Tissue crosslinking resulted in significant cytotoxicity in the direct vicinity of the suture (<3 mm). At larger distances from the suture, however, no difference in cell viability between the test and the control group was discernable. INTERPRETATION: The repair strength of a tendon-suture construct can be augmented by loading the suture with genipin. At this mechanically relevant dosage, crosslinking-induced cell death is confined to a radius of <3 mm from the suture in the short-term in-vitro setting. These promising results warrant further examination in-vivo.

Fabrication of self-healing injectable hyaluronic acid hydrogel for promoting angiogenesis / 上海交通大学学报（医学版）

Objective·To construct a self-healing injectable hyaluronic acid(HA)-based hydrogel(HAPD-Cu)and investigate the effects of different copper ions on the properties of the hydrogel and its vasogenic effiicacy to evaluate its feasibility for clinical wound healing.Methods·Bisphosphonated hyaluronic acid(HAPD)was prepared via a blue-light mediated thiol-ene click reaction between thiolated hyaluronic acid(HASH)and acrylated bisphosphonate(Ac-PD)in the presence of photoinitiator 2959.Then,HAPD was further interacted with Cu2+through metal coordination to prepare HAPD-Cu hydrogels with different Cu2+concentrations,i.e.HAPD-Cu1,HAPD-Cu2,HAPD-Cu3 and HAPD-Cu4.The molecular structures of HASH,Ac-PD,HAPD and HAPD-Cu were verified with 1HNMR and FTIR.Microscopic morphology of HAPD-Cu was observed under SEM.The shear-thinning and self-healing properties of HAPD-Cu were verified by rheometer.The Cu2+release from HAPD-Cu was determined with ICP.Live-dead staining and CCK-8 assay were applied to evaluate the biocompatibility of HAPD-Cu.The in vitro vasculogenic activity of HAPD-Cu was determined by a tubule-forming assay with human umbilical vein vascular endothelial cells and the in vivo vasculogenic activity of HAPD-Cu was assessed by CD31 tissue staining.A rat wound defect model was established in vitro to evaluate its actual repair effect.Results·The preparation of the materials was demonstrated through chemical qualitative and quantitative analytical means.In vitro studies showed that all HAPD-Cu with a loose porous internal structure exhibited outstanding self-healing,injectability and degradability,with a one-week degradation cycle and abrupt release behavior,which can meet the needs of wound healing cycle.All HAPD-Cu showed good biocompatibility except HAPD-Cu4,due to its high Cu2+concentrations.Moreover,its angiogenic effect in vitro or in vivo was enhanced with increasing Cu2+concentrations within the permissible Cu2+concentration range.In vitro wound model experiments also showed that the HAPD-Cu hydrogel significantly promoted wound healing compared with the control group.Conclusion·HAPD-Cu hydrogel constructed via the metal coordination shows excellent shape plasticity,allowing the filling of defective sites in a minimally invasive form,and the release of Cu2+greatly facilitates the establishment of early vascular networks,with giant potential for use in the repair of clinically irregular wounds.

Calcaneal reconstruction using a femoral head allograft and biologic adjuncts: A case report.

We present a case of calcaneal reconstruction after both an improvised explosive device injury and subsequent salvage procedures left the patient with a large calcaneal defect and damaged hindfoot soft tissue. A subtalar arthrodesis was performed with a femoral head allograft, where it was fused to the remaining calcaneus and superiorly through the talus, to successfully reconstruct this defect. Demineralized bone matrix, bone morphogenetic protein, and concentrated bone marrow aspirate were also added as adjuncts to promote bone remodeling. At final follow-up, the patient denied pain, was fully weight-bearing, and had resumed an active lifestyle. Level of Evidence: Level V, Case Report.

Xenograft-decellularized adipose tissue supports adipose remodeling in rabbit.

BACKGROUND: Decellularized adipose tissue (DAT) provides a suitable microenvironment for adipose stem cells (ADSCs) and promotes their adipogenic differentiation. Recent studies have focused on allogeneic DAT; however, insufficient adipose sources limit its wider application of allogeneic DAT. In this study, we compared the ability of allogeneic and xenogeneic DATs to induce adipose regeneration to explore the feasibility of xenogeneic DAT as an adjunctive material for tissue repair. METHODS: Decellularized adipose tissue from humans and rabbits was prepared using the Flynn's method. The proliferation, migration, and adipogenic functions of the allogeneic and the xenogeneic groups were compared. Rabbits were used to construct transplantation models: allogeneic (transplanted r-DAT) and xenogeneic groups (transplanted h-DAT). Comparison of DAT transplantation outcomes between the two groups. RESULTS: Xenogeneic DAT supports adipose regeneration. In vitro, adipose-derived stem cells cultured on xenogeneic DAT developed adipogenesis without media cues and were not statistically different from the effects of allogeneic DAT on cell migration, proliferation, and adipogenic capacity. In vivo, the animal model showed angiogenesis and adipogenesis, and the adipogenic ability of xenogeneic DAT was not statistically different from that of allogeneic DAT. CONCLUSION: Xenogeneic DATs can induce adipose regeneration, and its adipogenic ability has no statistical difference, compared with allogeneic DATs. Xenografts are expected to be useful for soft tissue repair.

Natural polymer-based scaffolds for soft tissue repair.

Soft tissues such as skin, muscle, and tendon are easily damaged due to injury from physical activity and pathological lesions. For soft tissue repair and regeneration, biomaterials are often used to build scaffolds with appropriate structures and tailored functionalities that can support cell growth and new tissue formation. Among all types of scaffolds, natural polymer-based scaffolds attract much attention due to their excellent biocompatibility and tunable mechanical properties. In this comprehensive mini-review, we summarize recent progress on natural polymer-based scaffolds for soft tissue repair, focusing on clinical translations and materials design. Furthermore, the limitations and challenges, such as unsatisfied mechanical properties and unfavorable biological responses, are discussed to advance the development of novel scaffolds for soft tissue repair and regeneration toward clinical translation.

Adhesive and biodegradable membranes made of sustainable catechol-functionalized marine collagen and chitosan.

We describe bioadhesive membranes developed from marine renewable biomaterials, namely chitosan and collagen extracted from fish skins. Collagen was functionalized with catechol groups (Coll-Cat) to provide the membranes with superior adhesive properties in a wet environment and blended with chitosan to improve the mechanical properties. The blended membranes were compared to chitosan and chitosan blended with unmodified collagen in terms of surface morphology, wettability, weight loss, water uptake, mechanical and adhesive properties. The metabolic activity, the viability and the morphology of L929 fibroblastic cells seeded on these membranes were also assessed. Our results show that the functionalization with catechol groups improves the adhesive and mechanical properties of the membranes and enhances cell attachment and proliferation. These data suggest that the developed marine origin-raw membranes present a potential towards the restoration of the structural and functional properties of damaged soft tissues.

Clinical Application of Bioresorbable, Synthetic, Electrospun Matrix in Wound Healing.

Electrospun polymeric matrices have long been investigated as constructs for use in regenerative medicine, yet relatively few have been commercialized for human clinical use. In 2017, a novel electrospun matrix, composed of two synthetic biocompatible polymers, polyglactin 910 (PLGA 10:90) and polydioxanone (PDO) of varying pore and fiber sizes (i.e., hybrid-scale) was developed and cleared by the FDA for human clinical use. The present review aims to explain the mechanism of action and review the preclinical and clinical results to summarize the efficacy of the matrix across multiple use cases within the wound care setting, including an assessment of over 150 wounds of varying etiologies treated with the synthetic matrix. Clinical data demonstrated effective use of the synthetic hybrid-scale fiber matrix across a variety of wound etiologies, including diabetic foot and venous leg ulcers, pressure ulcers, burns, and surgical wounds. This review represents a comprehensive clinical demonstration of a synthetic, electrospun, hybrid-scale matrix and illustrates its value and versatility across multiple wound etiologies.

Soft-Tissue Reconstruction of Complicated Total Ankle Arthroplasty.

BACKGROUND: Total ankle arthroplasty (TAA) is a popular modality to treat end-stage arthritis or internal ankle derangement. Unfortunately, failure rates remain undesirably high, with severe complications, including prosthesis failure, ankle fusion, and amputation. The importance of a stable soft-tissue envelope for coverage of implant compromise has been previously described, but the predictive factors for successful salvage of complicated TAA remain poorly understood. METHODS: A retrospective review was conducted of patients requiring soft-tissue reconstruction following TAA wound complications. Patient demographics, history, microbiological data, reconstructive approach, and outcomes data were collected. Statistical analysis was used to abstract factors associated with unsuccessful prosthetic salvage. RESULTS: In all, 13 patients met inclusion criteria: 8 (61.5%) achieved prosthetic salvage, and 5 (38.5%) failed. The majority (90.9%) of patients presented with infected joints. Reconstructive techniques included skin grafts, dermal substitutes, locoregional flaps, and free tissue transfer. Successful prosthetic salvage was associated with shorter time intervals between wound diagnosis and index reconstructive surgical intervention (median: 20 days for salvage vs 804 days for failure; P = .014). Additionally, salvage was associated with reduced time from the index orthopaedic/podiatric surgical intervention to the index reconstructive surgery procedure (12 vs 727 days; P = .027). CONCLUSION: The prognosis of complicated TAA requiring soft-tissue reconstruction remains poor, especially in patients who present with infected joints. Several reconstructive techniques, ranging from simple skin grafts to complex free tissue transfers, can be used successfully. Early intervention to achieve soft-tissue coverage is crucial in maximizing salvage rates in the setting of complicated and infected TAA. LEVEL OF EVIDENCE: Level IV.

Durability of transosseous repair of posterior soft tissues after primary total hip arthroplasty: a prospective randomized controlled trial.

PURPOSE: Posterior soft tissue repair is one of the methods for preventing dislocation after total hip arthroplasty (THA). This study aimed to evaluate durability of two separate suture materials in THA patients who underwent posterior soft tissue repair. METHODS: 42 THA patients were included in the study. The patients were randomly divided into two groups, where braided nonabsorbable suture was used in group A (n = 22), while braided absorbable suture was used in group B (n = 20). While repairing the posterior soft tissues, the piriformis and triceps coxae tendons together with the capsule were reattached to the greater trochanter via pull out sutures. Two hemoclips were attached as distance markers to both pull out sutures on the medial and lateal sides of the greater trochanter. Anteroposterior radiographs were taken one day, 15 days, 3 months and 6 months after operation. Distances between the hemoclips medial and lateral to the greater trochanter were measured on the radiographs, and the closest distances were recorded. The repair was considered a failure if the difference of distances between the first and any of the follow-up measurements exceeded 15 mm. RESULTS: No statistically significant difference was observed between the groups. In both groups, elongation magnitudes in all time intervals were statistically significant while the results obtained from measurements taken 15 days after operation were more significant (p < 0.01). No dislocations were observed. CONCLUSION: We conclude that for transosseous posterior soft tissue repair in THA, both absorbable and nonabsorbable sutures are similarly durable and can be routinely performed.

Vascularization strategies in tissue engineering approaches for soft tissue repair.

Insufficient vascularization during tissue repair is often associated with poor clinical outcomes. This is a concern especially when patients have critical-sized injuries, where the size of the defect restricts vascularity, or even in small defects that have to be treated under special conditions, such as after radiation therapy (relevant to tumor resection) that hinders vascularity. In fact, poor vascularization is one of the major obstacles for clinical application of tissue engineering methods in soft tissue repair. As a key issue, lack of graft integration, caused by inadequate vascularization after implantation, can lead to graft failure. Moreover, poor vascularization compromises the viability of cells seeded in deep portions of scaffolds/graft materials, due to hypoxia and insufficient nutrient supply. In this article we aim to review vascularization strategies employed in tissue engineering techniques to repair soft tissues. For this purpose, we start by providing a brief overview of the main events during the physiological wound healing process in soft tissues. Then, we discuss how tissue repair can be achieved through tissue engineering, and considerations with regards to the choice of scaffold materials, culture conditions, and vascularization techniques. Next, we highlight the importance of vascularization, along with strategies and methods of prevascularization of soft tissue equivalents, particularly cell-based prevascularization. Lastly, we present a summary of commonly used in vitro methods during the vascularization of tissue-engineered soft tissue constructs.

Deep Inferior Epigastric Flap Combined Bilateral-Anterolateral Thigh Flap for the Coverage of Both Lower Extremity Soft-Tissue Defect: A Case Report and a Literature Review.

BACKGROUND/PURPOSE: Anterolateral thigh perforator (ALTP) flap and deep inferior epigastric perforator (DIEP) flap have been advantageous over traditional myocutaneous flaps as they preserve the integrity of donor site muscles and minimize the damage and complication to donor site structures. Here, we reported the efficacy of free ALTP and DIEP in the repair of large skin area and soft tissue defects on both lower limbs after trauma. CASE REPORT: A 19-year-old female traffic accident victim presented with multiple open bilateral fractures to the lower extremities with joint dislocation, massive skin and soft tissue defects, and multiple soft tissue contusion. Wounds on both lower extremities were covered with VSD (Vacuum Sealing Drainage). The tibiofibular and ankle joints on both lower limbs were fixed using external fixators. DIEP and ALTP flap were performed at different times. RESULTS: After transfer, the vascular pedicle was anastomosed to the anterior tibial artery, posterior tibial artery, and the accompanying vein. After the operation, the donor site was directly closed and sutured. All flaps survived with a good appearance, leaving only a linear scar at the donor site. CONCLUSION: This case shows that free ALTP and DIEP flaps are ideal for repairing large skin area and soft tissue defects in bilateral lower limbs after trauma.

3D-Bioprinted Inflammation Modulating Polymer Scaffolds for Soft Tissue Repair.

Development of inflammation modulating polymer scaffolds for soft tissue repair with minimal postsurgical complications is a compelling clinical need. However, the current standard of care soft tissue repair meshes for hernia repair is highly inflammatory and initiates a dysregulated inflammatory process causing visceral adhesions and postsurgical complications. Herein, the development of an inflammation modulating biomaterial scaffold (bioscaffold) for soft tissue repair is presented. The bioscaffold design is based on the idea that, if the excess proinflammatory cytokines are sequestered from the site of injury by the surgical implantation of a bioscaffold, the inflammatory response can be modulated, and the visceral adhesion formations and postsurgical complications can be minimized. The bioscaffold is fabricated by 3D-bioprinting of an in situ phosphate crosslinked poly(vinyl alcohol) polymer. In vivo efficacy of the bioscaffold is evaluated in a rat ventral hernia model. In vivo proinflammatory cytokine expression analysis and histopathological analysis of the tissues have confirmed that the bioscaffold acts as an inflammation trap and captures the proinflammatory cytokines secreted at the implant site and effectively modulates the local inflammation without the need for exogenous anti-inflammatory agents. The bioscaffold is very effective in inhibiting visceral adhesions formation and minimizing postsurgical complications.

Comparison of Two Posterior Soft Tissue Repair Techniques to Prevent Dislocation after Total Hip Arthroplasty via the Posterolateral Approach.

BACKGROUND: Although the posterolateral approach is considered to carry a higher early dislocation rate after total hip arthroplasty, posterior soft tissue repair techniques make up for this limitation. Through-bone and through-tendon repair techniques are the two most commonly used techniques. This study aimed to comprehensively compare these techniques and give more evidence-based references for orthopedists. Methods: This retrospective study enrolled 87 patients who underwent posterior soft tissue repair with total hip arthroplasty via the posterolateral approach. The posterior capsular and external rotators were reconstructed to the greater trochanter through drill holes (through-bone, n = 46) or gluteus medius tendon (through-tendon, n = 41). Early dislocation rate, repair-related complications, postoperative pain (visual analog scale, VAS), hip joint function (Harris Hip Scale, HHS), patient satisfaction, and operation-related indexes were evaluated. Results: The discrepancy in early dislocation between the two cohorts was not statistically significant. Operation-related indexes were not significantly different between the two cohorts, except for the postoperative drainage volume (229.46 mL vs. 172.07 mL, p=.013). No patient sustained greater trochanteric fracture and sciatic nerve injury. Each group achieved significant improvements in HHS and VAS scores compared with preoperative values. No statistically significant discrepancy was found in HHS scores between the two groups at the same period, while VAS scores were significantly lower in the through-bone group at 1 week (4.93 vs. 5.68, p=.026) and 1 month (1.72 vs. 1.99, p=.038) after surgery. Higher patient satisfaction was observed in the through-bone group. Conclusions: Although no statistical discrepancy in the early dislocation rate between through-bone and through-tendon repair techniques was observed, lower pain scores and higher patient satisfaction supported the former. We recommend that through-bone repair technique should be chosen first by orthopedists when performing reconstruction of the posterior soft tissue in total hip arthroplasty via a posterolateral approach.

[Construction of tissue engineered adipose by human adipose tissue derived extracellular vesicle combined with decellularized adipose tissues scaffold].

OBJECTIVE: To explore the possibility of constructing tissue engineered adipose by adipose tissue derived extracellular vesicles (hAT-EV) combined with decellularized adipose tissue (DAT) scaffolds, and to provide a new therapy for soft tissue defects. METHODS: The adipose tissue voluntarily donated by the liposuction patient was divided into two parts, one of them was decellularized and observed by HE and Masson staining and scanning electron microscope (SEM). Immunohistochemical staining and Western blot detection for collagen type Ⅰ and Ⅳ and laminin were also employed. Another one was incubated with exosome-removed complete medium for 48 hours, then centrifuged to collect the medium and to obtain hAT-EV via ultracentrifugation. The morphology of hAT-EV was observed by transmission electron microscopy; the nanoparticle tracking analyzer (NanoSight) was used to analyze the size distribution; Western blot was used to analyse membrane surface protein of hAT-EV. Adipose derived stem cells (ADSCs) were co-cultured with PKH26 fluorescently labeled hAT-EV, confocal fluorescence microscopy was used to observe the uptake of hAT-EV by ADSCs. Oil red O staining was used to evaluate adipogenic differentiation after hAT-EV and ADSCs co-cultured for 15 days. The DAT was scissored and then injected into the bilateral backs of 8 C57 mice (6-week-old). In experimental group, 0.2 mL hAT-EV was injected weekly, and 0.2 mL PBS was injected weekly in control group. After 12 weeks, the mice were sacrificed, and the new fat organisms on both sides were weighed. The amount of new fat was evaluated by HE and peri-lipoprotein immunofluorescence staining to evaluate the ability of hAT-EV to induce adipogenesis in vivo. RESULTS: After acellularization of adipose tissue, HE and Masson staining showed that DAT was mainly composed of loosely arranged collagen with no nucleus; SEM showed that no cells and cell fragments were found in DAT, and thick fibrous collagen bundles could be seen; immunohistochemical staining and Western blot detection showed that collagen type Ⅰ and Ⅳ and laminin were retained in DAT. It was found that hAT-EV exhibited a spherical shape of double-layer envelope, with high expressions of CD63, apoptosis-inducible factor 6 interacting protein antibody, tumor susceptibility gene 101, and the particle size of 97.9% hAT-EV ranged from 32.67 nmto 220.20 nm with a peak at 91.28 nm. Confocal fluorescence microscopy and oil red O staining showed that hAT-EV was absorbed by ADSCs and induced adipogenic differentiation. In vivo experiments showed that the wet weight of fat new organisms in the experimental group was significantly higher than that in the control group ( t=2.278, P=0.048). HE staining showed that the structure of lipid droplets in the experimental group was more than that in the control group, and the collagen content in the control group was higher than that in the experimental group. The proportion of new fat in the experimental group was significantly higher than that in the control group ( t=4.648, P=0.017). CONCLUSION: DAT carrying hAT-EV can be used as a new method to induce adipose tissue regeneration and has a potential application prospect in the repair of soft tissue defects.

Construction of tissue engineered adipose by human adipose tissue derived extracellular vesicle combined with decellularized adipose tissues scaffold / 中国修复重建外科杂志

Objective: To explore the possibility of constructing tissue engineered adipose by adipose tissue derived extracellular vesicles (hAT-EV) combined with decellularized adipose tissue (DAT) scaffolds, and to provide a new therapy for soft tissue defects. Methods: The adipose tissue voluntarily donated by the liposuction patient was divided into two parts, one of them was decellularized and observed by HE and Masson staining and scanning electron microscope (SEM). Immunohistochemical staining and Western blot detection for collagen type Ⅰ and Ⅳ and laminin were also employed. Another one was incubated with exosome-removed complete medium for 48 hours, then centrifuged to collect the medium and to obtain hAT-EV via ultracentrifugation. The morphology of hAT-EV was observed by transmission electron microscopy; the nanoparticle tracking analyzer (NanoSight) was used to analyze the size distribution; Western blot was used to analyse membrane surface protein of hAT-EV. Adipose derived stem cells (ADSCs) were co-cultured with PKH26 fluorescently labeled hAT-EV, confocal fluorescence microscopy was used to observe the uptake of hAT-EV by ADSCs. Oil red O staining was used to evaluate adipogenic differentiation after hAT-EV and ADSCs co-cultured for 15 days. The DAT was scissored and then injected into the bilateral backs of 8 C57 mice (6-week-old). In experimental group, 0.2 mL hAT-EV was injected weekly, and 0.2 mL PBS was injected weekly in control group. After 12 weeks, the mice were sacrificed, and the new fat organisms on both sides were weighed. The amount of new fat was evaluated by HE and peri-lipoprotein immunofluorescence staining to evaluate the ability of hAT-EV to induce adipogenesis in vivo. Results: After acellularization of adipose tissue, HE and Masson staining showed that DAT was mainly composed of loosely arranged collagen with no nucleus; SEM showed that no cells and cell fragments were found in DAT, and thick fibrous collagen bundles could be seen; immunohistochemical staining and Western blot detection showed that collagen type Ⅰ and Ⅳ and laminin were retained in DAT. It was found that hAT-EV exhibited a spherical shape of double-layer envelope, with high expressions of CD63, apoptosis-inducible factor 6 interacting protein antibody, tumor susceptibility gene 101, and the particle size of 97.9% hAT-EV ranged from 32.67 nmto 220.20 nm with a peak at 91.28 nm. Confocal fluorescence microscopy and oil red O staining showed that hAT-EV was absorbed by ADSCs and induced adipogenic differentiation. In vivo experiments showed that the wet weight of fat new organisms in the experimental group was significantly higher than that in the control group ( t=2.278, P=0.048). HE staining showed that the structure of lipid droplets in the experimental group was more than that in the control group, and the collagen content in the control group was higher than that in the experimental group. The proportion of new fat in the experimental group was significantly higher than that in the control group ( t=4.648, P=0.017). Conclusion: DAT carrying hAT-EV can be used as a new method to induce adipose tissue regeneration and has a potential application prospect in the repair of soft tissue defects.