Autologous Split-thickness Skin Graft Research Articles

Nodular basal cell carcinoma on an autologous split-thickness skin graft after melanoma surgery.

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In vivo efficacy proof of concept of a large-size bioprinted dermo-epidermal substitute for permanent wound coverage.

Introduction: An autologous split-thickness skin graft (STSG) is a standard treatment for coverage of full-thickness skin defects. However, this technique has two major drawbacks: the use of general anesthesia for skin harvesting and scar sequelae on the donor site. In order to reduce morbidity associated with STSG harvesting, researchers have developed autologous dermo-epidermal substitutes (DESs) using cell culture, tissue engineering, and, more recently, bioprinting approaches. This study assessed the manufacturing reliability and in vivo efficacy of a large-size good manufacturing practice (GMP)-compatible bio-printed human DES, named Poieskin®, for acute wound healing treatment. Methods: Two batches (40cm2 each) of Poieskin® were produced, and their reliability and homogeneity were assessed using histological scoring. Immunosuppressed mice received either samples of Poieskin® (n = 8) or human STSG (n = 8) immediately after longitudinal acute full-thickness excision of size 1 × 1.5cm, applied on the skeletal muscle plane. The engraftment rate was assessed through standardized photographs on day 16 of the follow-up. Moreover, wound contraction, superficial vascularization, and local inflammation were evaluated via standardized photographs, laser Doppler imaging, and PET imaging, respectively. Histological analysis was finally performed after euthanasia. Results: Histological scoring reached 75% ± 8% and 73% ± 12%, respectively, displaying a robust and homogeneous construct. Engraftment was comparable for both groups: 91.8% (SD = 0.1152) for the Poieskin® group versus 100% (SD = 0) for the human STSG group. We did not record differences in either graft perfusion, PET imaging, or histological scoring on day 16. Conclusion: Poieskin® presents consistent bioengineering manufacturing characteristics to treat full-thickness cutaneous defects as an alternative to STSG in clinical applications. Manufacturing of Poieskin® is reliable and homogeneous, leading to a clinically satisfying rate of graft take compared to the reference human STSG in a mouse model. These results encourage the use of Poieskin® in phase I clinical trials as its manufacturing procedure is compatible with pharmaceutical guidelines.

575 Single-stage Trilaminar Skin Reconstruction Following Full-Thickness Burn Injury

Abstract Introduction Complex burns are highly morbid injuries that can cause severe disfigurement and can be devastating to one’s quality of life and psychosocial well-being. Currently, there are no simple, single-stage procedures available for extensive or multifocal burns to address full-thickness trilaminar defects. Our team has previously demonstrated the viability of an adipose-first reconstruction to address hypodermal defects. In this study, we demonstrate the efficacy of a combined adipose plus finely minced skin to achieve a single-stage trilaminar skin reconstruction. Methods Full-thickness burns were created on female Yorkshire swine. After 48-hours, escharectomies were performed to the level of fascia. The wounds were layered with adipose harvested from female Yorkshire swine. In one group, autologous split-thickness skin grafts were cut into pixel size (0.3x0.3 mm) grafts and layered on top of the adipose. Pigs were maintained for 4-weeks with weekly photography, ultrasound, followed by endpoint histology and tension measurements. Results At the end of the 4-week period, adipose combined with pixel graft demonstrated improved epithelialization and less contracture (p< 0.01). Thickness and mobility measurements were consistent in both groups. This findings were similar to our previous approaches using adipose following surgical debridement. Tissue pliability in the pixel grafting group was maintained to a high degree. Cross sections were performed which showed the persistence of fat graft at the base of the wounds. Conclusions Immediate, single-stage trilaminar reconstruction of full-thickness complex burns reduces contracture, mitigates adhesion, and restores normal soft-tissue thickness, therefore, presenting a paradigm changing approach in the current practice of burn injuries to the mobile surfaces. Applicability of Research to Practice Our results support the therapeutic potential of adipose-based soft-tissue reconstruction of burns to both enhance hypodermal augmentation and mitigate fibrotic complications including contracture and adhesions. Our data suggest that this approach is compatible with the standard of care skin grafting, and in fact provides improved epidermal thickness and pliability.

Surgical Treatment for Chest "Lock" Keloid Using Autologous Split-Thickness Skin Grafting and Postoperative Radiotherapy.

The treatment of chest "lock" keloids is challenging due to skin defects and a high recurrence rate. Evaluation of the effectiveness of autologous split-thickness skin graft with local radiotherapy for treating chest "lock" keloids. Fifty-seven patients with chest "lock" keloids were treated from July 2018 to September 2020. The skin defects were closed with an autologous split-thickness skin graft (STSG) and vacuum sealing drainage. The donor and the recipient sites received the first session of radiotherapy 72 hours postoperation for 3 consecutive days. Patients underwent follow-up examinations 12 months after surgery. The Patient and Observer Scar Assessment Scale (POSAS) was used to assess the treatment outcome. Except for the complaints of pain, which did not improve in the patients' assessments (p = .368), POSAS improved significantly after treatment (p < .0001). The cure rate (including cured and partially cured scars) was 100%. No keloid recurrence was observed during the follow-up period. The procedure of treating chest "lock" keloid by keloid debulking and autologous STSG followed by postoperational radiotherapy is a novel combined methodology for treating keloids.

Introduction to ECM Advances in Chinese Dermatologic Surgery.

We are pleased to present the Dermatologic Surgery Special Issue, which is focused on the extracellular matrix (ECM) in skin regeneration and dermopathy treatment. Regenerative medicine based on ECM is one of the most promising tools for skin rejuvenation and soft tissue regeneration. In addition, the occurrence of dermopathy is highly related to the disturbance of the ECM. In this issue, we provide the most recent advances in determining the role of the ECM in research and clinical application. This issue presents several articles on the cutting edge of dermatologic surgery. Dermatofibrosarcoma protuberans (DFSP) was discovered to have fibroblastic activity, and a variety of neural features were discovered, which validated DFSP’s fibroblastic origin and tendency toward neural differentiation. The efficacy and safety of picosecond laser therapy (PLT) was proven in the treatment of melasma. In addition, the efficacy and safety assessment found that the ECM is a dressing that promotes wound healing after PLT, which can shorten the downtime by alleviating erythema and edema and proceeding with scab shedding related to PLT. The treatment of keloids, a disease caused by ECM disorder, is an urgent problem in clinical practice. In this special issue, different keloid treatments are presented, including punch excision combined with drug injection, autologous split-thickness skin graft and postoperative radiotherapy, surgical excision with electron beam radiotherapy, and reduced incision tension of keloid surgery by tightening the fascia layer. The illumination of these promising strategies will be conducive to the development of future targeted therapies. Finally, we are fortunate to have several peer-reviewed literatures on the applications of ECM in skin regeneration medicine. Pingping Lin et al elucidated the dynamic composition and potential roles of the extracellular matrix in normal skin, the wound healing process, and abnormal skin scarring. Yixin Wang et al provided an overview of the clinical research, limitations, and potential application of botulinum toxin type A in the prevention and treatment of traumatic or postoperative scars. Weiyuan Zhang et al investigated the mechanism of Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) in reducing inflammation, promoting angiogenesis, promoting the proliferation and migration of epithelial cells and fibroblasts, and ECM remodeling during wound healing.

Efficacy of bioabsorbable dressing combined with antibacterial spray for treatment of third-degree burns.

To evaluate the clinical efficacy of a bioabsorbable dressing in combination with antibacterial spray in treating third-degree burns. Patients with third-degree burns in our hospital from February 2019 to February 2020 were enrolled and divided into an experimental group and a control group. In all patients, two wound repair surgeries were performed. During the first surgery, bioabsorbable dressing (PELNAC, Gunze Medical Equipment (Shenzhen) Co. Ltd., China) was used for wound treatment. During the second surgery, autologous split-thickness skin graft was performed. For patients in the experimental group, bioabsorbable dressings (PELNAC) were uniformly applied with antibacterial spray during the operation and during postoperative dressing. For patients in the control group, antibacterial spray was not used. A total of 68 patients took part in the study (experimental group n=36; control group n=32). Infection rate in the experimental group was significantly lower than that in the control group (2.8% versus 21.9%, respectively; p<0.05). The mean wound healing time in the experimental group was shorter by 3.2 days and the wound healing rate of the experimental group was significantly higher than that in the control group (p<0.05). Vancouver Scar Scale (VSS) scores at specific postoperative time intervals were significantly reduced in the experimental group compared with those in the control group (p<0.05). Bioabsorbable dressing combined with antibacterial spray could reduce infection rate, shorten wound healing time and reduce scar formation in repairing third-degree burns.

The clinical application effects of artificial dermis scaffold and autologous split-thickness skin composite grafts combined with vacuum-assisted closure in refractory wounds.

To investigate the clinical application effects of artificial dermis scaffold and autologous split-thickness skin composite grafts combined with vacuum-assisted closure (V.A.C) in refractory wounds. A retrospective analysis was performed on 70 patients with refractory wounds admitted to the First Affiliated Hospital of Soochow University from June 2019 to December 2021 (44 males and 25 females, with an average age of 49.3 ± 21.4 years). There were 26 patients with chronic ulcers; 3 patients with cancerous wounds; 16 patients with hot crush injuries; and 25 patients with traumatic wounds, including 21 cases of hands, 33 cases of feet, 6 cases of upper limbs, and 10 cases of lower limbs. The patients were divided into an artificial dermis scaffold group (35 patients, including 21 males and 14 females, aged 49.5 ± 21.3 years) and a skin graft group (35 patients, including 23 males and 11 females, aged 49.1 ± 21.5 years). In the artificial dermis scaffold group, after debridement, the artificial dermis scaffold was transplanted for approximately 2 weeks until the wound surface was well vascularized, after which the autologous split-thick skin graft was transplanted. Negative pressure wound therapy was performed throughout the treatment. In the skin grafting group, after debridement, the autologous split-thickness skin graft (aSTSG) was transplanted, and negative pressure wound therapy was performed continuously. The wound healing rate; skin graft survival rate; postoperative wound infection; exudative fluid volume; subcutaneous haematoma; hospitalisation time; hospitalisation cost; Vancouver Scar Scale (VSS) score, used to evaluate the scar of the recipient area at 6months after the operation; and the sensory disorder grading method, used to evaluate the sensory recovery of the recipient area, were compared between the two groups. All 70 refractory wounds healed. In the artificial dermis scaffold group, the skin graft survival rate was 90% (86%-95%), the hospitalisation time was 38 (29-45) days, the hospitalisation cost was 148 102 (118242-192327) yuan, and the VSS score was 1.9 ± 1.3. There were significant differences in skin graft survival rate (70% [60%-80%]), length of hospital stay (21 [14-28] days), hospitalisation cost (76 201 [39228-135 919] yuan) and VSS score [6.1 ± 3.6] between the skin graft group and the artificial dermis scaffold group (P < .05). The skin graft survival rate, scar hyperplasia and sensory recovery of the recipient area in the artificial dermis scaffold group were better than those in the skin graft group, but the hospitalisation time was relatively longer, and the hospitalisation cost was relatively higher. Wound healing rate, postoperative wound infection, exudate volume, and subcutaneous haematoma of patients in the two groups were similar, and there were no significant differences (P > .05). The artificial dermis scaffold and composite transplantation of autologous aSTSG with V.A.C can promote painless wound healing and improve the skin survival rate, skin colour and lustre, and flexible smooth texture and is conducive to less scar hyperplasia and postoperative functional exercise and recovery. This method provides a reasonable and effective scheme for the treatment of clinical refractory wounds.

Surgical Management of Hidradenitis Suppurativa: Factors Associated with Postoperative Complications and Disease Recurrence.

A retrospective cohort study of 65 patients surgically treated for HS at a tertiary care center was conducted. Patients' medical records were screened for demographical, clinical, and surgical characteristics. Statistical analysis was conducted to determine associations with postoperative complications and disease recurrence. Fifty patients (75.8%) were treated with systemic antibiotics before opting for surgical resection. Previous treatment with systemic rifampicin was associated with higher rates of postoperative complications (P = 0.029); however, systemic cephalexin and topical clindamycin were associated with a lower rate of complications (P = 0.007 and 0.040, accordingly). Medical history of smoking and surgical management with split-thickness skin grafts were associated with higher rates of postoperative complications (P = 0.012 and 0.014, accordingly). Patients with a greater number of lesions, and those treated with split-thickness skin graft, had higher rates of disease recurrence (P = 0.0018 and 0.003, accordingly).In a multivariate analysis a greater number of lesions (P = 0.0498) and the use of autologous split-thickness skin graft (P = 0.022) were independently associated with higher rates of disease recurrence. Previous conservative medical therapy bears the potential to modulate postoperative outcomes in HS patients, and should be taken into consideration. Despite reports of reliable results with split-thickness skin grafts, we found them to be associated with increased rates of diseases recurrence and postoperative complications.

A single-stage bilayered skin reconstruction using Glyaderm® as an acellular dermal regeneration template results in improved scar quality: an intra-individual randomized controlled trial

Absence of almost the entire reticular dermal layer is inherent to the use of autologous split-thickness skin grafting (STSG) to close full-thickness wounds, often resulting in hypertrophic scars and contractures. Many dermal substitutes have been developed, but unfortunately most have varying results in terms of cosmetic and/or functional improvement as well as patient satisfaction, in addition to high costs. Bilayered skin reconstruction using the human-derived glycerolized acellular dermis (Glyaderm®) has been reported to result in significantly improved scar quality using a two-step procedure. Unlike the necessary two-step procedure for most commercially available dermal substitutes, in this study we aimed to investigate the use of Glyaderm® in a more cost-effective single-stage engrafting. This is a method which, if autografts are available, is preferred by the majority of surgeons given the reduction in costs, hospitalization time and infection rate. A prospective, randomized, controlled, intra-individual, single-blinded study was performed, investigating the simultaneous application of Glyaderm® and STSG vs. STSG alone in full-thickness burns or comparable deep skin defects. During the acute phase, bacterial load, graft take and time to wound closure were assessed and were the primary outcomes. Aesthetic and functional results (secondary outcomes) were evaluated at 3, 6, 9 and 12months follow-up using subjective and objective scar measurement tools. Biopsies for histological analysis were taken at 3 and 12months. A total of 66 patients representing 82 wound comparisons were included. Graft take (>95%), pain management and healing time were comparable in both groups. At 1year follow-up, the overall Patient and Observer Scar Assessment Scale assessed by the patient was significantly in favour of sites where Glyaderm® was used. Not infrequently, patients attributed this difference to improved skin sensation. Histological analysis showed the presence of a well-formed neodermis, with donor elastin present for up to 12months. A single-stage bilayered reconstruction with Glyaderm® and STSG results in optimal graft take without loss of Glyaderm® nor the overlaying autografts due to infection. The presence of elastin in the neodermis was demonstrated during long-term follow-up in all but one patient, which is a crucial factor contributing to the significantly improved overall scar quality as evaluated by the blinded patients. The trial was registered on clinicaltrials.gov and received the following registration code: NCT01033604.

Advances in Skin Tissue Engineering and Regenerative Medicine.

There are an estimated 500,000 patients treated with full-thickness wounds in the United States every year. Fire-related burn injuries are among the most common and devastating types of wounds that require advanced clinical treatment. Autologous split-thickness skin grafting is the clinical gold standard for the treatment of large burn wounds. However, skin grafting has several limitations, particularly in large burn wounds, where there may be a limited area of non-wounded skin to use for grafting. Non-cellular dermal substitutes have been developed but have their own challenges; they are expensive to produce, may require immunosuppression depending on design and allogenic cell inclusion. There is a need for more advanced treatments for devastating burns and wounds. This manuscript provides a brief overview of some recent advances in wound care, including the use of advanced biomaterials, cell-based therapies for wound healing, biological skin substitutes, biological scaffolds, spray on skin and skin bioprinting. Finally, we provide insight into the future of wound care and technological areas that need to be addressed to support the development and incorporation of these technologies.

Application of collagen-chondroitin sulfate scaffolds with different pore sizes combined with acidic fibroblast growth factor in repairing full thickness skin defects in nude mice

Wound healing of skin defects is complex. For the treatment of large and deep wounds, it is a good alternative to accept artificial dermis grafting at the first stage surgery, and autologous split-thickness skin grafting 2–3 weeks later at the second stage surgery. In addition, the effectiveness of numerous cytokines such as fibroblast growth factor (FGF) on wounds healing has been widely researched. The traditional view is that direct external application or in vivo injection of exogenous FGFs may not achieve the desired therapeutic effect as the effective concentration cannot be maintained for a long time. Therefore, some researchers have tried to integrate various cytokines into skin substitutes for combined application. However, we believe that considering the current situation, it is still difficult to achieve mass production of these types of artificial dermis. Here, we manufactured a collagen-chondroitin sulfate scaffold material by imitating the marketed artificial dermis materials. Then, we combined it with recombinant human acidic FGF in a single full dose during the first-stage artificial dermis transplantation, which is simple and completely feasible but always controversial in the current clinical work, to explore whether this combinatorial therapy could serve as an efficient way wound healing in the Balb/c-nu mice full-thickness skin defect model.

Comparison of Glyaderm with different dermal substitute matrices in a porcine wound model

BackgroundThe closure of extensive burn wounds with widely expanded autologous split-thickness skin grafts (STSG) is associated with undesirable scar formation and contraction, due to the lack of dermis. Various materials for dermal replacement have been developed, either of xenogeneic, allogeneic or synthetic origin and are placed in the wound underneath a thin STSG in order to improve scar quality. In this study, a porcine wound model was used to compare several commercially available acellular dermal substitutes with an acellular dermal substitute prepared from glycerol preserved human skin: GlyadermⓇ. MethodsAntigenic components of the allografts were removed by incubation in the 0.06 M NaOH solution. In the first experiments, the dermal substitutes were applied to full thickness wounds and covered simultaneously with STSG. Controls were covered with STSG only. The wound healing response was analyzed for 8 weeks, both macroscopically and histologically. The Mann-Whitney U test was used for statistical analysis. In the second series of experiments, GlyadermⓇ was applied in a two-stage procedure in comparison to Integra. The STSG was placed on the dermal substitutes one week later. ResultsIn the first series, the inflammatory response and myofibroblast influx in GlyadermⓇ were limited, indicating possible beneficial outcomes on final wound healing results. The survival of the STSG on the acellular dermis was lower compared to the control wounds. Second series: the take of the STSG was the same as in the controls, but additionally wound contraction was reduced. The application of GlyadermⓇ was non-inferior to Integra. ConclusionGlyadermⓇ can be successfully used for the reduction of wound contraction when applied in a two-stage procedure.

Management of wounds with exposed bone structures using an induced-membrane followed by polymethyl methacrylate and second-stage skin grafting in the elderly with a 3-year follow-up.

The treatment of traumatic wounds with exposed bone or tendons is often challenging. An induced membrane (IM) is used to reconstruct bone defects, as it provides an effective and sufficient blood supply for bone and soft-tissue reconstruction. This study explored a novel two-stage strategy for wound management, consisting of initial wound coverage with polymethyl methacrylate (PMMA) and an autologous split-thickness skin graft under the IM. Fifty inpatients were enrolled from December 2016 to December 2019. Each patient underwent reconstruction according to a two-stage process. In the first stage, the defect area was thoroughly debrided, and the freshly treated wound was then covered using PMMA cement. After 4-6 weeks, during the second stage, the PMMA cement was removed to reveal an IM covering the exposed bone and tendon. An autologous split-thickness skin graft was then performed. Haematoxylin and eosin (H&E) staining and immunohistochemical analysis of vascular endothelial growth factor (VEGF), CD31 and CD34 were used to evaluate the IM and compare it with the normal periosteal membrane (PM). The psychological status and the Lower Extremity Function Scale (LEFS) as well as any complications were recorded at follow-up. We found that all skin grafts survived and evidenced no necrosis or infection. H&E staining revealed vascularised tissue in the IM, and immunohistochemistry showed a larger number of VEGF-, CD31- and CD34-positive cells in the IM than in the normal PM. The duration of healing in the group was 5.40 ± 1.32 months with a mean number of debridement procedures of 1.92 ± 0.60. There were two patients with reulceration in the group. The self-rating anxiety scale scores ranged from 35 to 60 (mean 48.02 ± 8.12). Postoperatively, the LEFS score was 50.10 ± 9.77. Finally, our strategy for the management of a non-healing wound in the lower extremities, consisting of an IM in combination with skin grafting, was effective, especially in cases in which bony structures were exposed in the elderly. The morbidity rate was low.

Outcomes Following Use of Negative-Pressure Wound Therapy Over Autologous Meshed and Non-Meshed Skin Grafts.

Negative-pressure wound therapy (NPWT) over split thickness skin grafts can control exudate, decrease infection rates, and improve revascularization. However, no study specifically addresses differences in outcomes between meshed/perforated and non-meshed autologous skin grafts dressed with NPWT. Through retrospective chart review, patients undergoing autologous split thickness skin grafting with a NPWT dressing for any burn injury over a 10-month period were identified. Data on etiology, graft take, meshed/perforated or non-meshed graft, graft size, and seroma/hematoma incidence were collected. Our study included 123 patients who had STSG with NPWT and consisted of 57% males, 57% Caucasian, and an average age of 41. Burn injury etiologies consisted of scald (55%), chemical (25%), flame (15%), and contact (5%). Average 2nd degree TBSA in our cohort was 2.34%, 3rd degree TBSA 4.50%, and total TBSA 5.35%. 66.7% of patients received non-meshed grafts, and these patients had an average graft area of 76.5 cm2. 33.3% of patients received meshed grafts, with an average graft area of 163.5 cm2. Non-meshed burn grafts were significantly smaller than meshed grafts (P = .04). There was 100% graft take and 0% seroma/hematoma formation in all patients. Data was analyzed using an unpaired student's T test and ANOVA testing. There were no statistically significant differences in patient demographics, or burn etiology. There exist many options for dressings after repair of burn injuries, each with its own unique advantages. There were, however, no differences in graft take or incidence of seroma/hematoma formation using a NPWT dressing over autologous meshed grafts vs non-meshed grafts. Our data shows that NPWT use as a bolster dressing is safe and efficacious overlying meshed skin grafts and non-meshed grafts.

Biomarkers of Skin Graft Healing in Venous Leg Ulcers.

There is a need for biomarkers that predict the success of transplantation of venous leg ulcers (with autologous split-thickness skin grafts). The primary objective of this exploratory study was to investigate the association between split-thickness skin graft healing in venous leg ulcers and candidate wound fluid biomarkers representing inflammatory cell and endogenous proteinase activities, and bioactivity. A secondary objective was to compare biomarker levels of the 17 venous leg ulcers with sterile split-thickness skin graft donor-site wounds in another 10 patients with venous leg ulcers. Wound fluids were collected for 24 h using a validated method. The concentration of pre-operative matrix metalloproteinase-9 in wound fluid was higher in venous leg ulcers showing good healing (n = 10) than in venous leg ulcers showing poor healing (n = 7) 12 weeks after transplantation with meshed split-thickness skin grafts. The diagnostic value of matrix metalloproteinase-9 was good according to receiver-operating characteristic curve analysis. Matrix metalloproteinase activity in wound fluids from split-thickness skin graft donor-site wounds increased as a function of time and healing, but was still lower than matrix metalloproteinase activity in venous leg ulcer wound fluids, which showed increased levels of most biomarkers except for matrix metalloproteinase-9 and matrix metalloproteinase-2. In conclusion, wound fluid matrix metalloproteinase-9 concentration is a potential predictive biomarker of split-thickness skin graft healing in venous leg ulcers.

Disrupting mechanotransduction decreases fibrosis and contracture in split-thickness skin grafting.

Burns and other traumatic injuries represent a substantial biomedical burden. The current standard of care for deep injuries is autologous split-thickness skin grafting (STSG), which frequently results in contractures, abnormal pigmentation, and loss of biomechanical function. Currently, there are no effective therapies that can prevent fibrosis and contracture after STSG. Here, we have developed a clinically relevant porcine model of STSG and comprehensively characterized porcine cell populations involved in healing with single-cell resolution. We identified an up-regulation of proinflammatory and mechanotransduction signaling pathways in standard STSGs. Blocking mechanotransduction with a small-molecule focal adhesion kinase (FAK) inhibitor promoted healing, reduced contracture, mitigated scar formation, restored collagen architecture, and ultimately improved graft biomechanical properties. Acute mechanotransduction blockade up-regulated myeloid CXCL10-mediated anti-inflammation with decreased CXCL14-mediated myeloid and fibroblast recruitment. At later time points, mechanical signaling shifted fibroblasts toward profibrotic differentiation fates, and disruption of mechanotransduction modulated mesenchymal fibroblast differentiation states to block those responses, instead driving fibroblasts toward proregenerative, adipogenic states similar to unwounded skin. We then confirmed these two diverging fibroblast transcriptional trajectories in human skin, human scar, and a three-dimensional organotypic model of human skin. Together, pharmacological blockade of mechanotransduction markedly improved large animal healing after STSG by promoting both early, anti-inflammatory and late, regenerative transcriptional programs, resulting in healed tissue similar to unwounded skin. FAK inhibition could therefore supplement the current standard of care for traumatic and burn injuries.

The urgent need to achieve an optimal strategic stock of human allogeneic skin graft materials in case of a mass disaster in Poland.

A burn is a sudden injury which immediate or long-term consequences may be life-threatening for the patient. A mass disaster event may involve large numbers of severely burned patients. Patients of this type typically have a limited area of healthy, unburned skin from which an autologous split thickness skin graft could be collected. In a clinical situation of this type, it is necessary to use a particular skin substitute. Non-viable allogeneic human skin graft materials might be considered as the most suitable skin substitutes in the treatment of such patients. At present, Poland does not have a sufficient supply of human allogeneic skin graft materials to meet the needs arising from a sudden and unforeseen mass disaster. This study involved an analysis of selected mass disasters. From this an estimate was made from a verified casualty profile of the necessary minimum stock of human allogeneic skin graft materials. An insufficient amount of skin results from an inadequate number of skin donors, which in turn results from the current tissue donation system. Therefore, a proposal has been made for the organizational, legal and systemic changes required to improve the situation in Polish transplantology, with particular emphasis on skin donation. In order to achieve a strategic stock of human skin grafts, a tissue collecting transplantation team should be organized. The rights and obligations of the non-physician transplant team member should be extended. Proposals have been made for awareness campaigns (adverts, posters etc.) and educational schemes (educational video, lectures during transplant coordinator training, etc.). Finally, a proposal has been made for possible methods to deal with the logistic management of the allogeneic skin stock. The required, essential stock of human allogeneic skin in the event of a mass disaster has been estimated at 600,000 cm2.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10561-022-10001-z.

Cellular Interaction of Human Skin Cells towards Natural Bioink via 3D-Bioprinting Technologies for Chronic Wound: A Comprehensive Review.

Skin substitutes can provide a temporary or permanent treatment option for chronic wounds. The selection of skin substitutes depends on several factors, including the type of wound and its severity. Full-thickness skin grafts (SGs) require a well-vascularised bed and sometimes will lead to contraction and scarring formation. Besides, donor sites for full-thickness skin grafts are very limited if the wound area is big, and it has been proven to have the lowest survival rate compared to thick- and thin-split thickness. Tissue engineering technology has introduced new advanced strategies since the last decades to fabricate the composite scaffold via the 3D-bioprinting approach as a tissue replacement strategy. Considering the current global donor shortage for autologous split-thickness skin graft (ASSG), skin 3D-bioprinting has emerged as a potential alternative to replace the ASSG treatment. The three-dimensional (3D)-bioprinting technique yields scaffold fabrication with the combination of biomaterials and cells to form bioinks. Thus, the essential key factor for success in 3D-bioprinting is selecting and developing suitable bioinks to maintain the mechanisms of cellular activity. This crucial stage is vital to mimic the native extracellular matrix (ECM) for the sustainability of cell viability before tissue regeneration. This comprehensive review outlined the application of the 3D-bioprinting technique to develop skin tissue regeneration. The cell viability of human skin cells, dermal fibroblasts (DFs), and keratinocytes (KCs) during in vitro testing has been further discussed prior to in vivo application. It is essential to ensure the printed tissue/organ constantly allows cellular activities, including cell proliferation rate and migration capacity. Therefore, 3D-bioprinting plays a vital role in developing a complex skin tissue structure for tissue replacement approach in future precision medicine.

Experimental study on the effect of three-dimensional porous structures on the vascularization rate of artificial dermis

Experimental study on the effect of three-dimensional porous structures on the vascularization rate of artificial dermis

Advances in Skin Tissue Bioengineering and the Challenges of Clinical Translation.

Skin tissue bioengineering is an emerging field that brings together interdisciplinary teams to promote successful translation to clinical care. Extensive deep tissue injuries, such as large burns and other major skin loss conditions, are medical indications where bioengineered skin substitutes (that restore both dermal and epidermal tissues) are being studied as alternatives. These may not only reduce mortality but also lessen morbidity to improve quality of life and functional outcome compared with the current standards of care. A common objective of dermal-epidermal therapies is to reduce the time required to accomplish stable closure of wounds with minimal scar in patients with insufficient donor sites for autologous split-thickness skin grafts. However, no commercially-available product has yet fully satisfied this objective. Tissue engineered skin may include cells, biopolymer scaffolds and drugs, and requires regulatory review to demonstrate safety and efficacy. They must be scalable for manufacturing and distribution. The advancement of technology and the introduction of bioreactors and bio-printing for skin tissue engineering may facilitate clinical products' availability. This mini-review elucidates the reasons for the few available commercial skin substitutes. In addition, it provides insights into the challenges faced by surgeons and scientists to develop new therapies and deliver the results of translational research to improve patient care.