Cutaneous Scarring: Basic Science, Current Treatments, and Future Directions

Helminth protein enhances wound healing by inhibiting fibrosis and promoting tissue regeneration

Skin wound healing due to full thickness wounds typically results in fibrosis and scarring, where parenchyma tissue is replaced with connective tissue. A major advance in wound healing research would be to instead promote tissue regeneration. Helminth parasites express excretory/secretory (ES) molecules, which can modulate mammalian host responses. One recently discovered ES protein, TGF-β mimic (TGM), binds the TGF-β receptor, though likely has other activities. Here, we demonstrate that topical administration of TGM under a Tegaderm bandage enhanced wound healing and tissue regeneration in an in vivo wound biopsy model. Increased restoration of normal tissue structure in the wound beds of TGM-treated mice was observed during mid- to late-stage wound healing. Both accelerated re-epithelialization and hair follicle regeneration were observed. Further analysis showed differential expansion of myeloid populations at different wound healing stages, suggesting recruitment and reprogramming of specific macrophage subsets. This study indicates a role for TGM as a potential therapeutic option for enhanced wound healing.

Navigating Scar Care: An Evaluation of Scar Treatment Patient Education Materials

While patient education materials (PEMs) across various specialties have been reported as being too difficult to read, the quality and understandability of PEMs related to scar management have not been assessed. In this study, we report the breadth of scar management interventions and readability of online PEMs authored by academic societies and university hospitals. Websites of academic medical societies and university hospitals with scar revision PEMs were assessed for relevance. PEM readability was assessed via Flesch Reading Ease, Flesch-Kincaid Grade Level, and Gunning-Fox Index scores. Understandability and actionability were evaluated using the Patient Education Material Assessment Tool (PEMAT). A total of 26 scar revision PEMs met the inclusion criteria. The most commonly mentioned scar management interventions were scar revision surgery (73%) and laser scar revision (70%), with minimal emphasis on noninvasive methods like scar massage or sun protection. Readability analysis yielded a mean Flesch reading level of 8.8. Overall, PEMAT understandability of online scar treatment PEMs was moderate, with a median of 76.0% (IQR 71.5%-80.5%). PEMs from all specialties and institution types were lacking in actionability, with median actionability of 40.8% (IQR 38.1%-60.0%). Online scar revision PEMs included a wide breadth of scar management interventions; however, the least costly interventions, such as sun protection and scar massage, were not commonly included. PEMs for scar management could be improved by simplifying language, including visual aids, and including checklists or specific steps, patients can take to take action on scar management interventions.

Advancements in stimulation therapies for peripheral nerve regeneration

Soft-tissue injuries affecting muscles, nerves, vasculature, tendons, and ligaments often diminish the quality of life due to pain, loss of function, and financial burdens. Both natural healing and surgical interventions can result in scarring, which potentially may impede functional recovery and lead to persistent pain. Scar tissue, characterized by a highly disorganized fibrotic extracellular matrix, may serve as a physical barrier to regeneration and drug delivery. While approaches such as drugs, biomaterials, cells, external stimulation, and other physical forces show promise in mitigating scarring and promoting regenerative healing, their implementation remains limited and challenging. Ultrasound, laser, electrical, and magnetic forms of external stimulation have been utilized to promote soft tissue as well as neural tissue regeneration. After stimulation, neural tissues experience increased proliferation of Schwann cells, secretion of neurotropic factors, production of myelin, and growth of vasculature, all aimed at supporting axon regeneration and innervation. Yet, the outcomes of healing vary depending on the pathophysiology of the damaged nerve, the timing of stimulation following injury, and the specific parameters of stimulation employed. Increased treatment intensity and duration have been noted to hinder the healing process by inducing tissue damage. These stimulation modalities, either alone or in combination with nerve guidance conduits and scaffolds, have been demonstrated to promote healing. However, the literature currently lacks a detailed understanding of the stimulation parameters used for nerve healing applications. In this article, we aim to address this gap by summarizing existing reports and providing an overview of stimulation parameters alongside their associated healing outcomes.

Cannabinoids in Integumentary Wound Care: A Systematic Review of Emerging Preclinical and Clinical Evidence

This systematic review critically evaluates preclinical and clinical data on the antibacterial and wound healing properties of cannabinoids in integument wounds. Comprehensive searches were conducted across multiple databases, including CINAHL, Cochrane library, Medline, Embase, PubMed, Web of Science, and LILACS, encompassing records up to May 22, 2024. Eighteen studies met the inclusion criteria. Eleven were animal studies, predominantly utilizing murine models (n = 10) and one equine model, involving 437 animals. The seven human studies ranged from case reports to randomized controlled trials, encompassing 92 participants aged six months to ninety years, with sample sizes varying from 1 to 69 patients. The studies examined the effects of various cannabinoid formulations, including combinations with other plant extracts, crude extracts, and purified and synthetic cannabis-based medications administered topically, intraperitoneally, orally, or sublingually. Four animal and three human studies reported complete wound closure. Hemp fruit oil extract, cannabidiol (CBD), and GP1a resulted in complete wound closure in twenty-three (range: 5-84) days with a healing rate of 66-86% within ten days in animal studies. One human study documented a wound healing rate of 3.3 cm2 over 30 days, while three studies on chronic, non-healing wounds reported an average healing time of 54 (21-150) days for 17 patients by oral oils with tetrahydrocannabinol (THC) and CBD and topical gels with THC, CBD, and terpenes. CBD and tetrahydrocannabidiol demonstrated significant potential in reducing bacterial loads in murine models. However, further high-quality research is imperative to fully elucidate the therapeutic potential of cannabinoids in the treatment of bacterial skin infections and wounds. Additionally, it is crucial to delineate the impact of medicinal cannabis on the various phases of wound healing. This study was registered in PROSPERO (CRD42021255413).

Pyroxylin-based liquid bandage forms a mechanically active protective film to facilitate skin wound healing in mice

Wound healing requires interplay between cells and molecules. Recent evidence has demonstrated that liquid bandages promote wound healing by forming a protective barrier against contamination, attenuating inflammation, and enhancing re-epithelialization and angiogenesis. In this study, we evaluated the wound healing activity of pyroxylin-based liquid bandage (LiQuiPlast®) in eight-week-old C57BL/6 male mice by generating a single 4 mm diameter full-thickness excisional skin wound on the dorsum. In the LiQuiPlast® group, the liquid bandage was applied on day 0 and was replaced every four days. Wound size was monitored every day for two weeks. The results showed that LiQuiPlast® was mechanically active (induced wound contraction), which promoted a significant wound size reduction (27 %-39 %, compared to the control group) on days 1-4 postinjury. In addition, a significant reduction in wound size was observed again in the LiQuiPlast® group (25 %-29 %, compared to the controls) on days 8-9 postinjury. LiQuiPlast®-treated wounds showed no scab. Immunohistochemistry analyses displayed a reduction in neutrophils and tumor necrosis factor-α levels in LiQuiPlast®-treated wounds, compared to the control group on day 4 postinjury (the inflammatory phase). In addition, LiQuiPlast®-treated mice had enhanced keratinocyte proliferation than control mice during this time. On day 13 postinjury, LiQuiPlast® significantly reduced hypertrophic scarring and enhanced expression and reorganization of collagen fiber compared to control mice. In conclusion, we show that LiQuiPlast® acts as a mechanically active protective film, which promotes moist wound healing by promoting wound contraction, no scab formation, attenuated inflammation, enhanced keratinocyte proliferation, and decreased scarring.

Verteporfin-Loaded Bioadhesive Nanoparticles for the Prevention of Hypertrophic Scar

Hypertrophic scarring (HS) is a common skin injury complication with unmet needs. Verteporfin (VP) should be an ideal HS-targeted therapeutic drug due to its efficient fibrosis and angiogenesis inhibitory abilities. However, its application is restricted by its side effects such as dose-dependent cytotoxicity on normal cells. Herein, the bioadhesive nanoparticles encapsulated VP (VP/BNPs) are successfully developed to attenuate the side effects of VP and enhance its HS inhibition effects by limiting VP releasing slowly and stably in the lesion site but not diffusing easily to normal tissues. VP/BNPs displayed significant inhibition on the proliferation, migration, collagen deposition, and vessel formation of human hypertrophic scar fibroblasts (HSFBs) and dermal vascular endothelial cells (HDVECs). In a rat tail HS model, VP/BNPs treated HS exhibits dramatic scar repression with almost no side effects compared with free VP or VP-loaded non-bioadhesive nanoparticles (VP/NNPs) administration. Further immunofluorescence analysis on scar tissue serial sections validated VP/BNPs effectively inhibited the collagen deposition and angiogenesis by firmly confined in the scar tissue and persistently releasing VP targeted to nucleus Yes-associated protein (nYAP) of HSFBs and HDVECs. These findings collectively suggest that VP/BNPs can be a promising and technically advantageous agent for HS therapies.

Pressure Injuries and Skin Failure

Pressure injuries are a common chronic wound in the older adult. Care of pressure injuries is an interprofessional effort and involves physicians, nurses, registered dieticians, rehabilitation therapists, and surgical subspecialties. Numerous treatment modalities exist but have varying evidence to substantiate their efficacy. All primary and other care providers, particularly geriatricians, need to be aware of current evidence-based prevention and treatment standards. When healing is not expected, palliative care should be considered to avoid futile procedures and preserve dignity and quality of life.

Effectiveness of Autologous Fat Grafting in the Treatment of Scars: A Systematic Review and Meta-Analysis

BACKGROUND

Autologous fat transfer (AFT) has been proposed as a possible treatment for scar tissue and its associated symptoms. Its effectiveness's evidence is yet unidentified though. The aim of this meta-analysis is to evaluate the currently available evidence on the efficacy and safety of autologous fat transfer in treating post-burn and post-traumatic scars using a validated scar measurement tool.

METHODS

This study performed a systematic literature review in November 2023 using the following electronic databases: MEDLINE, SCOPUS, Directory of Open Access Journals (DOAJ), PUBMED, and Google Scholar. The following key terms were included: (Fat grafting OR Autologous fat transfer) AND (body scars OR body burns OR body wounds) AND (Efficacy OR Safety OR satisfaction). We evaluated articles according to predefined quality criteria. The following data were included during the extraction period: patient demographics, indications for AFT, the number of AFT sessions, follow-up periods, and changes in the Patient and Observer Scar Assessment Scale (POSAS) scores, which contain both the patient and observer components.

RESULTS

This study included 1326 patients and 23 published articles. A total of 14 prospective studies, 7 retrospective studies, and 2 Randomized clinical trials studies were evaluated. These 23 articles came from diverse global locations; the earliest was published in 1992, and the most recently published in 2022.

CONCLUSION

Our findings demonstrated significant enhancements in scar characteristics from both patient and observer perspectives. Overall, AFT holds promise as a valuable treatment option for scar-related conditions as it enhances scar quality ,contributing to improved patient outcomes and satisfaction.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266.

Advances in skin gene therapy: utilizing innovative dressing scaffolds for wound healing, a comprehensive review

The skin, serving as the body's outermost layer, boasts a vast area and intricate structure, functioning as the primary barrier against external threats. Disruptions in the composition and functionality of the skin can lead to a diverse array of skin conditions, such as wounds, burns, and diabetic ulcers, along with inflammatory disorders, infections, and various types of skin cancer. These disorders not only exacerbate concerns regarding skin health and beauty but also have a significant impact on mental well-being. Due to the complexity of these disorders, conventional treatments often prove insufficient, necessitating the exploration of new therapeutic approaches. Researchers develop new therapies by deciphering these intricacies and gaining a thorough understanding of the protein networks and molecular processes in skin. A new window of opportunity has opened up for improving wound healing processes because of recent advancements in skin gene therapy. To enhance skin regeneration and healing, this extensive review investigates the use of novel dressing scaffolds in conjunction with gene therapy approaches. Scaffolds that do double duty as wound protectors and vectors for therapeutic gene delivery are being developed using innovative biomaterials. To improve cellular responses and speed healing, these state-of-the-art scaffolds allow for the targeted delivery and sustained release of genetic material. The most recent developments in gene therapy techniques include RNA interference, CRISPR-based gene editing, and the utilization of viral and non-viral vectors in conjunction with scaffolds, which were reviewed here to overcome skin disorders and wound complications. In the future, there will be rare chances to develop custom methods for skin health care thanks to the combination of modern technology and collaboration among disciplines.

Inhibition and reversal of a TGF-β1 induced myofibroblast phenotype by adipose tissue-derived paracrine factors

BACKGROUND

Hypertrophic scarring results from myofibroblast differentiation and persistence during wound healing. Currently no effective treatment for hypertrophic scarring exists however, autologous fat grafting has been shown to improve scar elasticity, appearance, and function. The aim of this study was to understand how paracrine factors from adipose tissues and adipose-derived stromal cells (ADSC) affect fibroblast to myofibroblast differentiation.

METHODS

The transforming growth factor-β1 (TGF-β1) induced model of myofibroblast differentiation was used to test the effect of conditioned media from adipose tissue, ADSC or lipid on the proportion of fibroblasts and myofibroblasts.

RESULTS

Adipose tissue conditioned media inhibited the differentiation of fibroblasts to myofibroblasts but this inhibition was not observed following treatment with ADSC or lipid conditioned media. Hepatocyte growth factor (HGF) was readily detected in the conditioned medium from adipose tissue but not ADSC. Cells treated with HGF, or fortinib to block HGF, demonstrated that HGF was not responsible for the inhibition of myofibroblast differentiation. Conditioned media from adipose tissue was shown to reduce the proportion of myofibroblasts when added to fibroblasts previously treated with TGF-β1, however, conditioned media treatment was unable to significantly reduce the proportion of myofibroblasts in cell populations isolated from scar tissue.

CONCLUSIONS

Cultured ADSC or adipocytes have been the focus of most studies, however, this work highlights the importance of considering whole adipose tissue to further our understanding of fat grafting. This study supports the use of autologous fat grafts for scar treatment and highlights the need for further investigation to determine the mechanism.

Application of supraclavicular island flap in oral and maxillofacial reconstruction

Several surgical modalities are available for maxillofacial reconstruction as locoregional or microvascular free flaps.

PURPOSE

(a) Evaluate the reliability of the supraclavicular flap in cervico-orofacial region; (b) investigate the role of computed tomography angiography (CTA) in predicting the post-operative viability of the flap; (c) assess the speech, feeding, and esthetics after reconstruction using this flap.

METHODS

Eleven patients included in this study underwent either conventional or delayed harvesting of the supraclavicular flap (SCF). All the patients had diagnostic computed tomography angiography (CTA) of the supraclavicular flap before the surgery.

RESULTS

The mean harvesting time of the flap was 45.45 ± 4.16 min. The average length of the flap was 22.64 ± 1.12 cm, whereas the mean width of the flap was 6.14 ± 1.14 cm. The flap survived in 9 patients, while two patients had complete flap loss. After the surgery, three patients complained of speech difficulties. Two patients had swallowing problems. After the surgery, three patients complained of speech difficulties. Two patients had swallowing problems. Only two patients complained of weakness in the donor site. None of the patients reported that the weakness or pain at the donor site affected their daily activities or quality of life.

CONCLUSION

The pedicled SCF represents a safe and feasible option that can be used to reconstruct a wide array of maxillofacial oncologic defects. However, a study with a larger sample size is recommended to achieve more reliable clinical results for the modified delayed technique modification in terms of their effect on the survival of the supraclavicular flap.

Scar Outcome in Unilateral Complete Cleft Lip Repair: A Comparative Analysis of Vertical Lip Lengthening Strategies Using the Rotation-Advancement Concept

OBJECTIVE

To assess the differences in scar outcomes between modified rotation-advancement techniques proposed by Drs. Mohler and Noordhoff, designed to address issues such as inadequate vertical lip length and scarring on the upper third of the lip in the original rotation-advancement technique.

DESIGN

Retrospective single-surgeon (RD) study.

PATIENTS

Consecutive non-syndromic children (n = 68) with unilateral complete cleft lip and palate.

INTERVENTIONS

Modified Mohler (columellar backcut reconstructed with C flap; n = 34) and modified Noordhoff (lower, medially-created backcut reconstructed with laterally-based triangular skin flap; n = 34) repairs.

MEAN OUTCOME MEASURES

Using 12-month postoperative frontal photographs, scar evaluations (overall and superior, middle, and inferior portions of the lip) were appraised by an assessment panel composed by independent professional and nonprofessional raters employing four validated qualitative scar assessment scales: Manchester Scar Scale, modified Scar-Rating Scale, Stony Brook Scar Evaluation Scale, and Visual Analog Scale. Quantitative computerized photogrammetric scar widths of the superior, middle, and inferior portions of the upper lip were also measured.

RESULTS

The modified Noordhoff method showed significantly (all P < .001) better scar quality for the overall scar and superior portion of the scar in all four scales compared to the modified Mohler method, with no significant (all P > .05) difference for the middle and lower portions. No significant difference (all P > .05) was observed for photogrammetric scar width measurements.

CONCLUSION

The modified Noordhoff technique provided better qualitative results for unilateral complete cleft lip-related scars compared to the modified Mohler technique.

Acne-induced pathological scars: pathophysiology and current treatments

Acne is a common chronic inflammatory dermatosis that can lead to pathological scars (PSs, divided into hypertrophic scars and keloids). These kinds of abnormal scars seriously reduce the quality of life of patients. However, their mechanism is still unclear, resulting in difficult clinical prevention, unstable treatment effects and a high risk of recurrence. Available evidence supports inflammatory changes caused by infection as one of the keys to abnormal proliferation of skin fibroblasts. In acne-induced PSs, increasing knowledge of the immunopathology indicates that inflammatory cells directly secrete growth factors to activate fibroblasts and release pro-inflammatory factors to promote the formation of PSs. T helper cells contribute to PSs via the secretion of interleukin (IL)-4 and IL-13, the pro-inflammatory factors; while regulatory T cells have anti-inflammatory effects, secrete IL-10 and prostaglandin E2, and suppress fibrosis production. Several treatments are available, but there is a lack of combination regimens to target different aspects of acne-induced PSs. Overall, this review indicates that the joint involvement of inflammatory response and fibrosis plays a crucial role in acne-induced PSs, and also analyzes the interaction of current treatments for acne and PS.

The scar-reducing effect of a novel chitosan gel: an in vivo study

OBJECTIVE

Scar tissue formation, as a normal part of wound healing, initiates in the proliferation phase, continues after the remodelling phase, and may cause an unpleasant appearance or disruption in normal functioning. This study investigated the effects of a topical gel on acute wound healing and reducing scars in a rat model.

METHOD

ChitoScar (ChitoTech Company, Iran), a commercial scar-reducing gel based on chitosan, was analysed for antibacterial and antiviral activity through a quantitative suspension test. Its cytotoxic effect was investigated, and then irritation and delayed-type hypersensitivity tests were carried out on rabbits through direct application of the gel. Furthermore, the effect of the chitosan-based gel on wound healing and scar tissue formation was studied in rats with an acute wound in two groups: the treatment group (topical application of the chitosan-based gel); and the control group (without treatment). Histopathological examination was carried out based on the inflammatory cells, collagen fibre, keratinocytes and fibroblasts.

RESULTS

Analysis revealed that the chitosan-based gel had no cytotoxicity and caused no erythema, oedema, local or other systemic adverse response. Wound healing occurred earlier in the treatment group, which was a result of a significant increase in re-epithelialisation, angiogenesis, fibroblast population and collagen fibre thickness (p<0.05). In the treatment group, wounds healed completely after 21 days and scars totally disappeared after 28 days, while in the control group, wound healing remained incomplete with distinct scar tissue.

CONCLUSION

The results demonstrated the positive effect of the chitosan-based gel on the duration and quality of the wound healing process, as well as minimising the scar tissue formation in this in vivo study.

Evaluating the impact of recombinant human epidermal growth factor on scar formation in oral and maxillofacial traumatic wound healing

Scarring following oral and maxillofacial trauma can have significant aesthetic and functional repercussions. Recombinant human epidermal growth factor (rhEGF) has emerged as a potential therapeutic agent to enhance wound healing and minimise scar formation. This retrospective study analysed data from March 2020 to June 2023 at a single institution. A total of 105 patients were divided into a control group (n = 70) receiving standard treatment and an observation group (n = 35) receiving standard treatment plus rhEGF. The primary outcomes were the incidence of scar hyperplasia and infection rates, with the secondary outcome being scar aesthetics measured by the visual analogue scale (VAS). No significant differences were found in baseline characteristics between the two groups. The observation group showed a significant reduction in scar hyperplasia (14.3% vs. 57.1%, χ2 = 20.98, p < 0.01) and infection rates (5.7% vs. 21.4%, χ2 = 4.246, p < 0.05) compared to the control group. VAS scores indicated a superior aesthetic outcome in the observation group at all post-treatment timepoints (p < 0.01). rhEGF treatment in oral and maxillofacial trauma patients resulted in favourable healing outcomes and reduced scar formation, improving aesthetic results. These findings highlight the therapeutic potential of rhEGF and underscore the need for larger-scale trials to further investigate its benefits.

Morphological characteristics of facial scars: A retrospective analysis according to scar location, onset, age, and cause

The morphology of facial scars shows a wide variation in terms of texture and colour. To date, there are no reliable predictors of aberrant scarring. We conducted a retrospective analysis to identify factors associated with specific scar features and types. Photographs and medical records of 428 patients with facial scars were retrospectively reviewed. Patients with keloids were excluded. The mean age of the patients was 45.43 ± 23.13 years with a male-to-female ratio of 1:1.36. Atrophic scars were the most common (42.8%), followed by flat scars (38.7%) and hypertrophic scars (18.5%). Scars on the forehead were more likely to be atrophic, whereas scars on the chin/jaw and around the mouth were more likely to be hypertrophic. Hypopigmentation was significantly more common in scars located on the forehead. Redness (erythema) was significantly more common in scars located on the chin/jaw. Old scars were less likely to be erythematous, and hypertrophic. Atrophic scars were more common in younger patients. Scars caused by dermatologic conditions, such as acne, were more likely to be atrophic, whereas surgical scars had the lowest risk of being atrophic or hypertrophic. In conclusion, the location, onset, and cause of facial scars were associated with specific features of scars.

Impact of Incisional Access Site in Primary Breast Augmentation: Evaluation of Patient Satisfaction with SCAR-Q

BACKGROUND

Scarring at the incision site represents one of the most impactful outcomes in breast augmentation surgery for both the patient and the surgeon. Few studies exist with the aim of assessing patient perception of scarring outcomes in primary breast augmentation. The aim of this study was to evaluate the impact on quality of life of scars by submitting the SCAR-Q in patients who underwent primary augmentation mammoplasty.

METHODS

The SCAR-Q was administered at one and at 6 months after surgery to 54 consecutive patients underwent primary breast augmentation with inferior hemi-periareolar or inframammary incision. A total of 50 patients were divided into two groups of 21 patients with inferior hemi-periareolar incision and 29 patients with inframammary fold incision, respectively. Statistical analysis was performed with Prism 9.

RESULTS

All mean values of the three SCAR-Q scales tend to decrease at the second administration meaning that the perception of the scar is better at time 6 from the patient perspective. In the "Psychosocial scale," lower values at both 1 month and 6 months for group 2 compared to group 1 were shown. Unpaired T tests with Welch's correction showed significance for delta values variations between the two groups with P values <0.0001.

CONCLUSION

Data show that patients undergoing primary breast augmentation have a scar that has no significant impact. Patients with inframammary fold scar have less psychosocial impact than those with inferior hemi-periareolar scar. There were no statistically significant differences in scar-related symptoms and scar appearance between scar along the inframammary groove and inferior hemi-periareolar scar.

LEVEL OF EVIDENCE IV

Case series study. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266 .

Fractional CO₂ Laser Therapy for Effective Treatment of Facial Traumatic Hypertrophic Scar: A Case Report

BACKGROUND Hypertrophic scars occur when there is an excessive wound-healing response in the skin. Fractional, or fractionated, carbon dioxide (CO₂) laser therapy uses narrow shafts of light to smooth the skin surface and stimulate dermal collagen, which tightens the skin. This case report describes a 57-year-old woman with a traumatic hypertrophic scar of the face treated with fractional carbon dioxide laser therapy. The purpose of this case report was to highlight the role of fractional CO₂ laser therapy in treatment of a facial traumatic hypertrophic scar in a patient after a motor vehicle crash. CASE REPORT A 57-year-old female patient presented with a hypertrophic, rigid, post-traumatic scar on the left side of her face following a motor vehicle crash. For the hypertrophic scar removal, the patient underwent 1 treatment session with fractional CO₂ laser using the µ-Scan DOT scanning system. After 1 laser treatment session, the photographic documentation, which permits monitoring the treatment's effectiveness in esthetic improvement, showed a significant improvement in scar texture and color. In addition, a significant reduction in scar height was observed following laser therapy. Fractional laser treatment with the device was very well tolerated by the patient, who reported no pain or discomfort, complications, or adverse effects either during treatment or in the follow-up period (3 months). CONCLUSIONS This report demonstrates the cosmetic application of fractional carbon dioxide laser therapy in a case of hypertrophic scar with the use of an effective therapeutic protocol that did not require the use of suturing.

Modeling the extracellular matrix in cell migration and morphogenesis: a guide for the curious biologist

The extracellular matrix (ECM) is a highly complex structure through which biochemical and mechanical signals are transmitted. In processes of cell migration, the ECM also acts as a scaffold, providing structural support to cells as well as points of potential attachment. Although the ECM is a well-studied structure, its role in many biological processes remains difficult to investigate comprehensively due to its complexity and structural variation within an organism. In tandem with experiments, mathematical models are helpful in refining and testing hypotheses, generating predictions, and exploring conditions outside the scope of experiments. Such models can be combined and calibrated with in vivo and in vitro data to identify critical cell-ECM interactions that drive developmental and homeostatic processes, or the progression of diseases. In this review, we focus on mathematical and computational models of the ECM in processes such as cell migration including cancer metastasis, and in tissue structure and morphogenesis. By highlighting the predictive power of these models, we aim to help bridge the gap between experimental and computational approaches to studying the ECM and to provide guidance on selecting an appropriate model framework to complement corresponding experimental studies.

Dual delivery gene-activated scaffold directs fibroblast activity and keratinocyte epithelization

Fibroblasts are the most abundant cell type in dermal skin and keratinocytes are the most abundant cell type in the epidermis; both play a crucial role in wound remodeling and maturation. We aim to assess the functionality of a novel dual gene activated scaffold (GAS) on human adult dermal fibroblasts (hDFs) and see how the secretome produced could affect human dermal microvascular endothelial cells (HDMVECs) and human epidermal keratinocyte (hEKs) growth and epithelization. Our GAS is a collagen chondroitin sulfate scaffold loaded with pro-angiogenic stromal derived factor (SDF-1α) and/or an anti-aging β-Klotho plasmids. hDFs were grown on GAS for two weeks and compared to gene-free scaffolds. GAS produced a significantly better healing outcome in the fibroblasts than in the gene-free scaffold group. Among the GAS groups, the dual GAS induced the most potent pro-regenerative maturation in fibroblasts with a downregulation in proliferation (twofold, p < 0.05), fibrotic remodeling regulators TGF-β1 (1.43-fold, p < 0.01) and CTGF (1.4-fold, p < 0.05), fibrotic cellular protein α-SMA (twofold, p < 0.05), and fibronectin matrix deposition (twofold, p < 0.05). The dual GAS secretome also showed enhancements of paracrine keratinocyte pro-epithelializing ability (1.3-fold, p < 0.05); basement membrane regeneration through laminin (6.4-fold, p < 0.005) and collagen IV (8.7-fold, p < 0.005) deposition. Our findings demonstrate enhanced responses in dual GAS containing hDFs by proangiogenic SDF-1α and β-Klotho anti-fibrotic rejuvenating activities. This was demonstrated by activating hDFs on dual GAS to become anti-fibrotic in nature while eliciting wound repair basement membrane proteins; enhancing a proangiogenic HDMVECs paracrine signaling and greater epithelisation of hEKs.

Dual Glyoxalase-1 and β-Klotho Gene-Activated Scaffold Reduces Methylglyoxal and Reprograms Diabetic Adipose-Derived Stem Cells: Prospects in Improved Wound Healing

Tissue engineering approaches aim to provide biocompatible scaffold supports that allow healing to progress often in healthy tissue. In diabetic foot ulcers (DFUs), hyperglycemia impedes ulcer regeneration, due to complications involving accumulations of cellular methylglyoxal (MG), a key component of oxidated stress and premature cellular aging which further limits repair. In this study, we aim to reduce MG using a collagen-chondroitin sulfate gene-activated scaffold (GAS) containing the glyoxalase-1 gene (GLO-1) to scavenge MG and anti-fibrotic β-klotho to restore stem cell activity in diabetic adipose-derived stem cells (dADSCs). dADSCs were cultured on dual GAS constructs for 21 days in high-glucose media in vitro. Our results show that dADSCs cultured on dual GAS significantly reduced MG accumulation (-84%; p < 0.05) compared to the gene-free controls. Similar reductions in profibrotic proteins α-smooth muscle actin (-65%) and fibronectin (-76%; p < 0.05) were identified in dual GAS groups. Similar findings were observed in the expression of pro-scarring structural proteins collagen I (-62%), collagen IV (-70%) and collagen VII (-86%). A non-significant decrease in the expression of basement membrane protein E-cadherin (-59%) was noted; however, the dual GAS showed a significant increase in the expression of laminin (+300%). We conclude that dual GAS-containing Glo-1 and β-klotho had a synergistic MG detoxification and anti-fibrotic role in dADSC's. This may be beneficial to provide better wound healing in DFUs by controlling the diabetic environment and rejuvenating the diabetic stem cells towards improved wound healing.

Hydrogel-mediated extracellular vesicles for enhanced wound healing: the latest progress, and their prospects for 3D bioprinting

Extracellular vesicles have shown promising tissue recovery-promoting effects, making them increasingly sought-after for their therapeutic potential in wound treatment. However, traditional extracellular vesicle applications suffer from limitations such as rapid degradation and short maintenance during wound administration. To address these challenges, a growing body of research highlights the role of hydrogels as effective carriers for sustained extracellular vesicle release, thereby facilitating wound healing. The combination of extracellular vesicles with hydrogels and the development of 3D bioprinting create composite hydrogel systems boasting excellent mechanical properties and biological activity, presenting a novel approach to wound healing and skin dressing. This comprehensive review explores the remarkable mechanical properties of hydrogels, specifically suited for loading extracellular vesicles. We delve into the diverse sources of extracellular vesicles and hydrogels, analyzing their integration within composite hydrogel formulations for wound treatment. Different composite methods as well as 3D bioprinting, adapted to varying conditions and construction strategies, are examined for their roles in promoting wound healing. The results highlight the potential of extracellular vesicle-laden hydrogels as advanced therapeutic tools in the field of wound treatment, offering both mechanical support and bioactive functions. By providing an in-depth examination of the various roles that these composite hydrogels can play in wound healing, this review sheds light on the promising directions for further research and development. Finally, we address the challenges associated with the application of composite hydrogels, along with emerging trends of 3D bioprinting in this domain. The discussion covers issues such as scalability, regulatory considerations, and the translation of this technology into practical clinical settings. In conclusion, this review underlines the significant contributions of hydrogel-mediated extracellular vesicle therapy to the field of 3D bioprinting and wound healing and tissue regeneration. It serves as a valuable resource for researchers and practitioners alike, fostering a deeper understanding of the potential benefits, applications, and challenges involved in utilizing composite hydrogels for wound treatment.

Non-invasive imaging of pathological scars using a portable handheld two-photon microscope

BACKGROUND

Pathological scars are a disorder that can lead to various cosmetic, psychological, and functional problems, and no effective assessment methods are currently available. Assessment and treatment of pathological scars are based on cutaneous manifestations. A two-photon microscope (TPM) with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo . This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients.

METHODS

Fifteen patients with pathological scars and three healthy controls were recruited. Imaging was performed using a portable handheld TPM. Five indexes were extracted from two dimensional (2D) and three dimensional (3D) perspectives, including collagen depth, dermo-epidermal junction (DEJ) contour ratio, thickness, orientation, and occupation (proportion of collagen fibers in the field of view) of collagen. Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images. We assessed index differences between scar and normal skin and changes before and after treatment.

RESULTS

Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers. Five indexes were employed to distinguish between normal skin and scar tissue. Statistically significant differences were found in average depth ( t = 9.917, P <0.001), thickness ( t = 4.037, P <0.001), occupation ( t = 2.169, P <0.050), orientation of collagen ( t = 3.669, P <0.001), and the DEJ contour ratio ( t = 5.105, P <0.001).

CONCLUSIONS

Use of portable handheld TPM can distinguish collagen from skin tissues; thus, it is more suitable for scar imaging than reflectance confocal microscopy. Thus, a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.

Evaluating the Irritant Factors of Silicone and Hydrocolloid Skin Contact Adhesives Using Trans-Epidermal Water Loss, Protein Stripping, Erythema, and Ease of Removal

A composite silicone skin adhesive material was designed to improve its water vapor permeability to offer advantages to wearer comfort compared to existing skin adhesive dressings available (including perforated silicone and hydrocolloid products). The chemical and mechanical properties of this novel dressing were analyzed to show that it has a high creep compliance, offering anisotropic elasticity that is likely to place less stress on the skin. A participant study was carried out in which 31 participants wore a novel silicone skin adhesive (Sil2) and a hydrocolloid competitor and were monitored for physiological response to the dressings. Trans-epidermal water loss (TEWL) was measured pre- and postwear to determine impairment of skin barrier function. Sil2 exhibited a higher vapor permeability than the hydrocolloid dressings during wear. Peel strength measurements and dye counter staining of the removed dressings showed that the hydrocolloid had a higher adhesion to the participants' skin, resulting in a greater removal of proteins from the stratum corneum and a higher pain rating from participants on removal. Once the dressings were removed, TEWL of the participants skin beneath the Sil2 was close to normal in comparison to the hydrocolloid dressings that showed an increase in skin TEWL, indicating that the skin had been highly occluded. Analysis of the skin immediately after removal showed a higher incidence of erythema following application of hydrocolloid dressings (>60%) compared to Sil2, (<30%). In summary, this modified silicone formulation demonstrates superior skin protection properties compared to hydrocolloid dressings and is more suitable for use as a skin adhesive.

The efficacy of adipose-derived stem cells in burn injuries: a systematic review

BACKGROUND

Burn injuries can be associated with prolonged healing, infection, a substantial inflammatory response, extensive scarring, and eventually death. In recent decades, both the mortality rates and long-term survival of severe burn victims have improved significantly, and burn care research has increasingly focused on a better quality of life post-trauma. However, delayed healing, infection, pain and extensive scar formation remain a major challenge in the treatment of burns. ADSCs, a distinct type of mesenchymal stem cells, have been shown to improve the healing process. The aim of this review is to evaluate the efficacy of ADSCs in the treatment of burn injuries.

METHODS

A systematic review of the literature was conducted using the electronic databases PubMed, Web of Science and Embase. The basic research question was formulated with the PICO framework, whereby the usage of ADSCs in the treatment of burns in vivo was determined as the fundamental inclusion criterion. Additionally, pertinent journals focusing on burns and their treatment were screened manually for eligible studies. The review was registered in PROSPERO and reported according to the PRISMA statement.

RESULTS

Of the 599 publications screened, 21 were considered relevant to the key question and were included in the present review. The included studies were almost all conducted on rodents, with one exception, where pigs were investigated. 13 of the studies examined the treatment of full-thickness and eight of deep partial-thickness burn injuries. 57,1 percent of the relevant studies have demonstrated that ADSCs exhibit immunomodulatory effects during the inflammatory response. 16 studies have shown improved neovascularisation with the use of ADSCs. 14 studies report positive influences of ADSCs on granulation tissue formation, while 11 studies highlight their efficacy in promoting re-epithelialisation. 11 trials demonstrated an improvement in outcomes during the remodelling phase.

CONCLUSION

In conclusion, it appears that adipose-derived stem cells demonstrate remarkable efficacy in the field of regenerative medicine. However, the usage of ADSCs in the treatment of burns is still at an early experimental stage, and further investigations are required in order to examine the potential usage of ADSCs in future clinical burn care.

Use of a collagen-elastin matrix with split-thickness skin graft for defect coverage in complex wounds

OBJECTIVE

Severe soft tissue damage with destruction of the dermis requires plastic reconstructive treatment. For multimorbid patients or patients unable to undergo major reconstructive surgery, use of dermal substitutes, such as a collagen-elastin matrix (CEM) with a split-thickness skin graft (STSG), instead of local or free flap surgery, may be a valid and easy treatment option. We aimed to investigate and compare the outcomes and rate of successful defect reconstruction using CEM plus STSG, using either a one-step approach (simultaneous CEM and STSG) or a two-step approach (CEM and negative wound pressure therapy (NPWT), with secondary STSG transplantation).

METHOD

A single-centre, retrospective follow-up study of patients who had received CEM was conducted. Wounds had been treated with an STSG transplantation covering a CEM (MatriDerm, MedSkin Solutions Dr. Suwelack AG, Germany). Previous attempts at wound closure with conventional methods had failed in the selected patient population, which would usually have resulted in flap surgery.

RESULTS

Overall, 46 patients were included (mean age 60.9±20.0 years), with a total of 49 wound sites. We analysed 38 patients with wounds that did not require flap coverage; 18 patients received the one-step approach and 20 patients received the two-step approach. The mean follow-up in these patients was 22±11.5 months, and one patient was lost to follow-up. Overall, 29 (78.4%) wounds remained closed. Wounds which did not successfully heal were related to comorbidities, such as diabetes, alcohol misuse and smoking. Using the one-step approach, long-term defect coverage was achieved in 13 (76.5%) wounds and 16 (80.0%) wounds were closed using the two-step approach. However, there was no statistically significant differences between the one- or two-step approaches regarding the rate of development of a wound healing disorder.

CONCLUSION

Wound closure was achieved in 38 complex wounds using CEM plus STSG, while 11 wounds needed secondary flap coverage. In the flap-free wounds, there were no statistically significant differences between the one-step versus two-step approach. Using a simple defect reconstruction algorithm, we successfully used CEM plus STSG to treat complex wounds.

Development of a bioactive silk fibroin bilayer scaffold for wound healing and scar inhibition

In cases of deep skin defects, spontaneous tissue regeneration and excessive collagen deposition lead to hyperplastic scars. Conventional remedial action after scar formation is limited with a high recurrence rate. In this study, we designed a new artificial skin bilayer using silk fibroin nanofibers films (SNF) as the epidermis, and silk fibroin (SF) / hyaluronic acid (HA) scaffold as the dermal layer. The regenerated SF film was used as a binder to form a functional SNF-SF-HA bilayer scaffold. The bilayer scaffold showed high porosity, hydrophilicity, and strength, and retained its shape over 30 days in PBS. In vitro, human umbilical vein endothelial cells were seeded into the bilayer scaffold and showed superior cell viability. In vivo analyses using the rabbit ear hypertrophic scar (HS) model indicated that the bilayer scaffold not only supported the reconstruction of new tissue, but also inhibited scar formation. The scaffold possibly achieved scar inhabitation by reducing wound contraction, weakening inflammatory reactions, and regulating collagen deposition and type conversion, which was partly observed through the downregulation of type I collagen, transforming growth factor-β, and α-smooth muscle actin. This study describes a new strategy to expand the application of silk-based biomaterials for the treatment of hyperplastic skin scars.

Fibrosis in burns: an overview of mechanisms and therapies

Scar development remains a common occurrence and a major healthcare challenge affecting the lives of millions of patients annually. Severe injuries to the skin, such as burns can lead to pathological wound healing patterns, often characterized by dermal fibrosis or excessive scarring, and chronic inflammation. The two most common forms of fibrotic diseases following burn trauma are hypertrophic scars (HSCs) and keloids, which severely impact the patient's quality of life. Although the cellular and molecular mechanisms are similar, HSC and keloids have several distinct differences. In this review, we discuss the different forms of fibrosis that occur postburn injury, emphasizing how the extent of burn influences scar development. Moreover, we highlight how a systemic response induced by a burn injury drives wound fibrosis, including both the role of the inflammatory response, as well as the fate of fibroblast during skin healing. Finally, we list potential therapeutics aimed at alleviating pathological scar formation. An understanding of the mechanisms of postburn fibrosis will allow us to effectively move studies from bench to bedside.

Minimal scarring in a premature neonate

Background

Scar formation and management is one of the major issues in plastic surgery. Scars are a chronic burden to patients, their families, and the wider healthcare system and while non-surgical and surgical options have been shown to reduce scarring and its impact, there are currently no therapeutic options to completely heal scars or to avoid scarring. Early gestation animals have been reported to heal skin wounds without scarring.

Case presentation

We report on a premature, underweight-for-age neonate of 30 weeks' gestation that suffered a combination of deep partial thickness abrasions and full thickness wounds following birth trauma, who eventually healed with minimal skin scarring.

Conclusion

This case highlights that more research is needed to understand the mechanism and timelines of foetal skin healing, so the knowledge can be used to develop better therapeutic options to treat skin scars in adults.

Effectiveness of Mesenchymal Stem Cell Secretome on Wound Healing: A Systematic Review and Meta-analysis

BACKGROUND

Secretome provides promising potential in replacing cell-based therapies in wound repair therapy. This study aimed to systematically review and conduct a meta-analysis on the effectiveness of secretome in promoting wound healing.

METHODS

To ensure the rigor and transparency of our study, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, as registered in PROSPERO with ID: CRD42023412671. We conducted a comprehensive search on four electronic databases to identify studies evaluating the effect of secretome on various clinical parameters of wound repair. In addition, we evaluated the risk of bias for each study using the Jadad and Newcastle-Ottawa scale. To synthesize the data, we employed a fixed-effects model and calculated the mean difference or odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

Based on six included articles, secretome is known to affect several clinical parameters in wound healing included the size and depth of ulcers during healing; the E´chelle d'évaluation clinique des cicatrices d'acne (ECCA) score, epidermal thickness, collagen fibers, abnormal elastic tissues, volume of atrophic acne scars, skin pore volume, and erythema during acne scar healing; and microcrust areas, erythema index, transepidermal water loss, volume of atrophic acne scars, erythema, and relative gene expression of procollagen type I, procollagen type III, and elastin were evaluated in wound healing after laser treatment. Meta-analysis studies showed that secretome reduced ulcer size (mean difference: 0.87, 95% CI of 0.37-1.38, p = 0.0007), decreased ulcer depth (mean difference: 0.18, 95% CI of 0.11-0.25, p < 0.00001), and provided patient satisfaction (odds ratio: 9.71, 95% CI of 3.47-21.17, p < 0.0001). However, secretome failed to reach significance in clinical improvement (OR 0.38, 95% CI 0.10, 1.53, p = 0.06).

CONCLUSION

The secretome provides good effectiveness in accelerating wound healing through a mechanism that correlates with several clinical parameters of wound repair.

Exploring the Role of Spatial Confinement in Immune Cell Recruitment and Regeneration of Skin Wounds

Microporous annealed particle (MAP) scaffolds are injectable granular materials comprised of micron sized hydrogel particles (microgels). The diameter of these microgels directly determines the size of the interconnected void space between particles where infiltrating or encapsulated cells reside. This tunable porosity allows the authors to use MAP scaffolds to study the impact of spatial confinement (SC) on both cellular behaviors and the host response to biomaterials. Despite previous studies showing that pore size and SC influence cellular phenotypes, including mitigating macrophage inflammatory response, there is still a gap in knowledge regarding how SC within a biomaterial modulates immune cell recruitment in vivo in wounds and implants. Thus, the immune cell profile within confined and unconfined biomaterials is studied using small (40 µm), medium (70 µm), and large (130 µm) diameter spherical microgels, respectively. This work uncovered that MAP scaffolds impart regenerative wound healing with an IgG1-biased Th2 response. MAP scaffolds made with large microgels promote a balanced pro-regenerative macrophage response, resulting in enhanced wound healing with mature collagen regeneration and reduced inflammation levels.

Greater Patient Satisfaction With Use of Nonabsorbable Sutures Compared to Absorbable Sutures for Skin Closure Following Knee Arthroscopy: A Randomized Controlled Trial

Purpose

The purpose of this study was to evaluate patient outcomes and satisfaction after arthroscopic portal closure with absorbable versus nonabsorbable sutures after knee arthroscopy.

Methods

Patients undergoing primary knee arthroscopy were identified during procedure scheduling. Exclusion criteria included revision procedures, concomitant ligament reconstruction, or meniscal repair surgery. Before surgery, enrolled patients were randomly assigned to undergo closure with either 3-0 Monocryl absorbable or 3-0 nylon non-absorbable sutures. Postoperative evaluation at 2, 6, and 12 weeks included a Visual Analogue Cosmesis scale, a 10-point visual analogue scale (VAS) for pain, patient scar assessment, and customized questionnaire assessing scar satisfaction.

Results

Between January 2019 and August 2022, 247 were included for analysis: 145 in the absorbable group and 129 in the non-absorbable group. There was no significant difference between groups in terms of age, sex, body mass index, race, smoking status, or laterality of procedure. Patients in the nonabsorbable group reported higher overall satisfaction at week 6 follow-up (9.12 ± 1.85 vs 8.44 ± 2.49, P = .019) and week 12 follow-up (9.13 ± 1.76 vs 8.54 ± 2.50, P = .048). There was no difference in pain, swelling, itching, numbness, incisional pain, or burning at any time. Patients in the nonabsorbable group observed more skin discoloration at 2 weeks (3.00 ± 2.33 vs 2.41 ± 1.80, P = .026) and 6 weeks (3.74 ± 2.82 vs 2.98 ± 2.45, P = .032) follow-up with no significant difference at 12 weeks.

Conclusion

In this study, patients were more satisfied with nonabsorbable sutures for portal wound closure after knee arthroscopy despite early reporting of increased skin discoloration relative to absorbable sutures.

Level of Evidence

Level I, randomized controlled trial.

Regulatory T cells in skin regeneration and wound healing

As the body's integumentary system, the skin is vulnerable to injuries. The subsequent wound healing processes aim to restore dermal and epidermal integrity and functionality. To this end, multiple tissue-resident cells and recruited immune cells cooperate to efficiently repair the injured tissue. Such temporally- and spatially-coordinated interplay necessitates tight regulation to prevent collateral damage such as overshooting immune responses and excessive inflammation. In this context, regulatory T cells (Tregs) hold a key role in balancing immune homeostasis and mediating cutaneous wound healing. A comprehensive understanding of Tregs' multifaceted field of activity may help decipher wound pathologies and, ultimately, establish new treatment modalities. Herein, we review the role of Tregs in orchestrating the regeneration of skin adnexa and catalyzing healthy wound repair. Further, we discuss how Tregs operate during fibrosis, keloidosis, and scarring.

Silk Bioprotein as a Novel Surgical-Site Wound Dressing: A Prospective, Randomized, Single-Blinded, Superiority Clinical Trial

Background

Medical adhesive-related skin injuries (MARSIs) affect about 1.5 million patients annually in the United States. Complications include allergic contact dermatitis, skin blistering, skin tears, and surgical-site infections (SSIs). The authors hypothesize that a natural hypoallergenic silk bioprotein wound dressing will decrease the incidence of MARSI in comparison to a synthetic alternative.

Objectives

This study aimed to assess the efficacy and safety of a silk bioprotein wound dressing compared to the Dermabond Prineo (Ethicon, Inc., Somerville, NJ) skin closure system.

Methods

This prospective, randomized, single-blinded trial studied 25 patients who were dressed with Dermabond Prineo on one side of their body and on the contralateral side with the silk bioprotein dressing after undergoing abdominoplasty or reduction mammaplasty procedures. Data were collected over 5 postoperative visits using photographs and an investigator administered questionnaire to track rash, itch, discomfort, erythema, edema, SSIs, need for pharmaceutical intervention, mechanical injury, removal time, and bathing routines.

Results

Sixty-four percent (16/25) of patients characterized the severity of discomfort as a score of 4 out of 10 or greater on the Dermabond Prineo control side and only 4% (1/25) for the silk-dressing side (P < .001). Fifty-two percent (13/25) had a visible rash of 4 or higher on the Dermabond Prineo side of their incision and 0% (0/25) had a rash on the silk side (P < .001). Fifty-two percent (13/25) required steroids or antibiotics to treat MARSI to Dermabond Prineo and 0% (0/25) required pharmaceutical intervention on the silk side (P < .001).

Conclusions

The use of a silk bioprotein wound dressing significantly reduces the incidence of MARSI throughout the postoperative period.

Level of Evidence 2

ECM-Focused Proteomic Analysis of Ear Punch Regeneration in Acomys Cahirinus

In mammals, significant injury is generally followed by the formation of a fibrotic scar which provides structural integrity but fails to functionally restore damaged tissue. Spiny mice of the genus Acomys represent the first example of full skin autotomy in mammals. Acomys cahirinus has evolved extremely weak skin as a strategy to avoid predation and is able to repeatedly regenerate healthy tissue without scar after severe skin injury or full-thickness ear punches. Extracellular matrix (ECM) composition is a critical regulator of wound repair and scar formation and previous studies have suggested that alterations in its expression may be responsible for the differences in regenerative capacity observed between Mus musculus and A. cahirinus , yet analysis of this critical tissue component has been limited in previous studies by its insolubility and resistance to extraction. Here, we utilize a 2-step ECM-optimized extraction to perform proteomic analysis of tissue composition during wound repair after full-thickness ear punches in A. cahirinus and M. musculus from weeks 1 to 4 post-injury. We observe changes in a wide range of ECM proteins which have been previously implicated in wound regeneration and scar formation, including collagens, coagulation and provisional matrix proteins, and matricryptic signaling peptides. We additionally report differences in crosslinking enzyme activity and ECM protein solubility between Mus and Acomys. Furthermore, we observed rapid and sustained increases in CD206, a marker of pro-regenerative M2 macrophages, in Acomys, whereas little or no increase in CD206 was detected in Mus. Together, these findings contribute to a comprehensive understanding of tissue cues which drive the regenerative capacity of Acomys and identify a number of potential targets for future pro-regenerative therapies.

Artificial Skin Therapies; Strategy for Product Development

Significance: Tissue-engineered artificial skin for clinical reconstruction can be regarded as an established practice. Bi-layered skin equivalents are available as established allogenic or autologous therapy, and various acellular skin replacements can support tissue repair. Moreover, there is considerable commonality between the skin and other soft tissue reconstruction products. This article presents an attempt to create a comprehensive global landscape review of advanced replacement materials and associated strategies for skin and soft tissue reconstruction. Recent Advances: There has been rapid growth in the number of commercial and pre-commercial products over the past decade. In this survey, 263 base products for advanced skin therapy have been identified, across 8 therapeutic categories, giving over 350 products in total. The largest market is in the United States, followed by the E.U. zone. However, despite these advances, and the investment of resources in each product development, there are key issues concerning the clinical efficacy, cost-benefit of products, and clinical impact. Each therapeutic strategy has relative merits and limitations. Critical Issues: A critical consideration in developing and evaluating products is the therapeutic modality, associated regulatory processes, and the potential for clinical adoption geographically, determined by regulatory territory, intellectual property, and commercial distribution factors. The survey identifies an opportunity for developments that improve basic efficacy or cost-benefit. Future Directions: The economic pressures on health care systems, compounded by the demands of our increasingly ageing population, and the imperative to distribute effective health care, create an urgent global need for effective and affordable products.

Current and Future Developments in Wound Healing

Poor wound healing on the face and neck can lead to significant morbidity and dissatisfaction in facial plastic surgery. With current advances in wound healing management and commercially available biologic and tissue-engineered products, there are several options available to optimize acute wound healing and treat delayed or chronic wounds. This article summarizes some of the key principals and recent developments in wound healing research in addition to potential future advancements in the field of soft tissue wound healing.

Osteopathic Approach for Keloids and Hypertrophic Scars

The skin is a complex organ, a system that influences and is influenced by the body system, with different skin layers always mechano-biologically active. In the presence of a lesion that damages the dermis, the skin undergoes sensory, morphological, and functional alterations. The subsequent adaptation is the formation of scar tissue, following distinct and overlapping biological phases. For reasons not yet fully elucidated, some healing processes lead to pathological scars, from which symptoms such as pain, itching, and functional limitations are derived. Currently, there is no gold standard treatment that fully meets the needs of different scars and can eliminate any symptoms that the patient suffers. One such treatment is manual medicine, which involves direct manual approaches to the site of injury. Reviewing the phases that allow the skin to be remodeled following an injury, this article reflects on the usefulness of resorting to these procedures, highlighting erroneous concepts on which the manual approach is based, compared to what the current literature highlights the cicatricial processes. Considering pathological scar adaptations, it would be better to follow a gentle manual approach.

Treatment of traumatic hypertrophic scars and keloids: a systematic review of randomized control trials

Exaggerated healing and remodeling after skin injury may cause hypertrophic and keloidal scars, which are associated with functional and quality of life impairment. There is limited guidance available regarding the relative effectiveness of therapies for hypertrophic scars and keloids. In this review, we aim to compare the effectiveness of treatments for hypertrophic scars and keloids. MEDLINE, Embase, Scopus, and the Cochrane Collaboration database were searched from inception to March 2019 for randomized control trials of treatments for hypertrophic and keloid scars that included 20 or more patients. Outcomes evaluated included the standardized mean reduction in scarring and adverse events. The type of scar and the demographic features were analyzed for their effect on clinical outcome. Based on 25 included clinical trials, intralesional injection (64.1% [95% CI 60.8-67.5%]) may be more effective than physical (29.9% [95% CI 28.9-30.9%]) or topical treatments (34% [95% CI 31.8-36.8%]). Combination of 5-fluorouracil and triamcinolone (9:1 dilution) appeared superior among intralesional treatments for keloids. Ablative laser and pulsed-dye laser were the most useful laser treatments. Regression modeling showed laser treatment response was linked to Fitzpatrick skin type (p = 0.002). Adverse events were uncommon for all treatments and mostly transient. Intralesional treatments for keloid and hypertrophic scars may be the most reliable treatment option to improve pathologic scars, while laser treatment may have specific benefits for Fitzpatrick skin types I-III over types IV-VI. Management of pathological scars is an area of critical need, where appropriate treatment can have a significant impact on quality of life.

Nano drug delivery systems: a promising approach to scar prevention and treatment

Scar formation is a common physiological process that occurs after injury, but in some cases, pathological scars can develop, leading to serious physiological and psychological effects. Unfortunately, there are currently no effective means to intervene in scar formation, and the structural features of scars and their unclear mechanisms make prevention and treatment even more challenging. However, the emergence of nanotechnology in drug delivery systems offers a promising avenue for the prevention and treatment of scars. Nanomaterials possess unique properties that make them well suited for addressing issues related to transdermal drug delivery, drug solubility, and controlled release. Herein, we summarize the recent progress made in the use of nanotechnology for the prevention and treatment of scars. We examine the mechanisms involved and the advantages offered by various types of nanomaterials. We also highlight the outstanding challenges and questions that need to be addressed to maximize the potential of nanotechnology in scar intervention. Overall, with further development, nanotechnology could significantly improve the prevention and treatment of pathological scars, providing a brighter outlook for those affected by this condition.

Mesodermal Derivatives of Pluripotent Stem Cells Route to Scarless Healing

Scar formation during normal tissue regeneration in adults may result in noticeable cosmetic and functional defects and have a significant impact on the quality of life. In contrast, fetal tissues in the mid-gestation period are known to be capable of complete regeneration with the restitution of the initial architecture, organization, and functional activity. Successful treatments that are targeted to minimize scarring can be realized by understanding the cellular and molecular mechanisms of fetal wound regeneration. However, such experiments are limited by the inaccessibility of fetal material for comparable studies. For this reason, the molecular mechanisms of fetal regeneration remain unknown. Mesenchymal stromal cells (MSCs) are central to tissue repair because the molecules they secrete are involved in the regulation of inflammation, angiogenesis, and remodeling of the extracellular matrix. The mesodermal differentiation of human pluripotent stem cells (hPSCs) recapitulates the sequential steps of embryogenesis in vitro and provides the opportunity to generate the isogenic cell models of MSCs corresponding to different stages of human development. Further investigation of the functional activity of cells from stromal differon in a pro-inflammatory microenvironment will procure the molecular tools to better understand the fundamental mechanisms of fetal tissue regeneration. Herein, we review recent advances in the generation of clonal precursors of primitive mesoderm cells and MSCs from hPSCs and discuss critical factors that determine the functional activity of MSCs-like cells in a pro-inflammatory microenvironment in order to identify therapeutic targets for minimizing scarring.

Fire Needle Combined Topical Mupirocin for the Treatment of Simple Skin Abscesses in Pediatric Patients: A Case Series

Background

Skin abscesses are a common skin condition usually caused by bacterial infections and their incidence is increasing in children. Its current management strategy is still mainly incision and drainage, sometimes with antibiotics. In pediatric patients, surgical incision and drainage of skin abscesses is challenging compared to in adults because of their specific age and psychological characteristics and high aesthetic requirements. Therefore, it is important to seek better treatment options.

Patients and methods

We reported 17 cases of skin abscesses in pediatric patients aged 1 to 9 years. Ten cases had lesions on the face and neck and 7 cases on the trunk and limbs. They all received treatment based on fire needle combined with topical mupirocin.

Results

The lesions of all 17 pediatric patients healed within 4 to 14 days, with a median time of 6 days, and all achieved satisfactory results with no scarring left behind. No adverse events were observed in all patients, and no recurrence occurred within 4 weeks.

Conclusion

For skin abscesses in pediatric patients, early application of a combination therapy based on fire needle is convenient, aesthetic, economical, safe and clinically important as an alternative to incision and drainage, and deserves further clinical promotion.

Microfibril-associated protein 5 and the regulation of skin scar formation

Many factors regulate scar formation, which yields a modified extracellular matrix (ECM). Among ECM components, microfibril-associated proteins have been minimally explored in the context of skin wound repair. Microfibril-associated protein 5 (MFAP5), a small 25 kD serine and threonine rich microfibril-associated protein, influences microfibril function and modulates major extracellular signaling pathways. Though known to be associated with fibrosis and angiogenesis in certain pathologies, MFAP5's role in wound healing is unknown. Using a murine model of skin wound repair, we found that MFAP5 is significantly expressed during the proliferative and remodeling phases of healing. Analysis of existing single-cell RNA-sequencing data from mouse skin wounds identified two fibroblast subpopulations as the main expressors of MFAP5 during wound healing. Furthermore, neutralization of MFAP5 in healing mouse wounds decreased collagen deposition and refined angiogenesis without altering wound closure. In vitro, recombinant MFAP5 significantly enhanced dermal fibroblast migration, collagen contractility, and expression of pro-fibrotic genes. Additionally, TGF-ß1 increased MFAP5 expression and production in dermal fibroblasts. Our findings suggest that MFAP5 regulates fibroblast function and influences scar formation in healing wounds. Our work demonstrates a previously undescribed role for MFAP5 and suggests that microfibril-associated proteins may be significant modulators of wound healing outcomes and scarring.

Immune cells and associated molecular markers in dermal fibrosis with focus on raised cutaneous scars

Raised dermal scars including hypertrophic, and keloid scars as well as scalp-associated fibrosing Folliculitis Keloidalis Nuchae (FKN) are a group of fibrotic raised dermal lesions that mostly occur following cutaneous injury. They are characterized by increased extracellular matrix (ECM) deposition, primarily excessive collagen type 1 production by hyperproliferative fibroblasts. The extent of ECM deposition is thought to be proportional to the severity of local skin inflammation leading to excessive fibrosis of the dermis. Due to a lack of suitable study models, therapy for raised dermal scars remains ill-defined. Immune cells and their associated markers have been strongly associated with dermal fibrosis. Therefore, modulation of the immune system and use of anti-inflammatory cytokines are of potential interest in the management of dermal fibrosis. In this review, we will discuss the importance of immune factors in the pathogenesis of raised dermal scarring. The aim here is to provide an up-to-date comprehensive review of the literature, from PubMed, Scopus, and other relevant search engines in order to describe the known immunological factors associated with raised dermal scarring. The importance of immune cells including mast cells, macrophages, lymphocytes, and relevant molecules such as cytokines, chemokines, and growth factors, antibodies, transcription factors, and other immune-associated molecules as well as tissue lymphoid aggregates identified within raised dermal scars will be presented. A growing body of evidence points to a shift from proinflammatory Th1 response to regulatory/anti-inflammatory Th2 response being associated with the development of fibrogenesis in raised dermal scarring. In summary, a better understanding of immune cells and associated molecular markers in dermal fibrosis will likely enable future development of potential immune-modulated therapeutic, diagnostic, and theranostic targets in raised dermal scarring.

Potential Role of AGR2 for Mammalian Skin Wound Healing

The limited ability of mammals to regenerate has garnered significant attention, particularly in regard to skin wound healing (WH), which is a critical step for regeneration. In human adults, skin WH results in the formation of scars following injury or trauma, regardless of severity. This differs significantly from the scarless WH observed in the fetal skin of mammals or anamniotes. This review investigates the role of molecular players involved in scarless WH, which are lost or repressed in adult mammalian WH systems. Specifically, we analyze the physiological role of Anterior Gradient (AGR) family proteins at different stages of the WH regulatory network. AGR is activated in the regeneration of lower vertebrates at the stage of wound closure and, accordingly, is important for WH. Mammalian AGR2 is expressed during scarless WH in embryonic skin, while in adults, the activity of this gene is normally inhibited and is observed only in the mucous epithelium of the digestive tract, which is capable of full regeneration. The combination of AGR2 unique potencies in postnatal mammals makes it possible to consider it as a promising candidate for enhancing WH processes.

Tailored versus conventional surgical debridement in complex facial lacerations in emergency department: A retrospective study

Surgical debridement is an essential step in treating complex facial lacerations (CFL). As the CFL severity increases, conventional surgical debridement (CSD) of wound edges becomes difficult and may be insufficient. Because the severity and shape of each CFL vary, it is necessary to tailor the customized pre-excisional design, that is, tailored surgical debridement (TSD), for each case before performing surgical debridement. The use of TSD can enable effective debridement of CFL with higher severity. This study aimed to compare the cosmetic outcomes and complication incidence of CSD versus TSD according to CFL severity. In this retrospective observational study, eligible patients with CFL who visited the emergency department between August 2020 and December 2021 were examined. CFL severity was graded as Grades I and II. The outcomes of CSD and TSD were compared using the scar cosmesis assessment and rating (SCAR) scale, wherein a good cosmetic outcome was defined as a SCAR score of ≤ 2. The percentage of good cosmetic outcomes between the 2 groups was compared. The SCAR score and percentage of good cosmetic outcomes between the 2 groups were compared overall and by severity. For analyzing complication incidence, asymmetry, infection, and dehiscence incidence were compared. In total, 252 patients were enrolled [121 (48.0%) CSD and 131 (52.0%) TSD]. The median SCAR scores were 3 (1-5) and 1 (0-2) in all enrolled patients (P < .001), 2 (0-4), and 1 (0-1) in Grade I patients (P < .01), and 5 (4-6) and 1 (1-2) in Grade II patients (P < .001) in the CSD and TSD groups, respectively. The percentage of good cosmetic outcomes was 46.3% and 84.0% overall (P < .001), 59.6% and 85.0% in Grade I patients (P < .01), and 9.4% and 83.5% in Grade II patients (P < .001) in the CSD and TSD groups, respectively. The incidence of complications was significantly higher in the CSD group than in the TSD group, but this was limited to asymmetry. No significant difference was noted in infection or dehiscence. Compared with CSD, TSD can lead to an objectively good cosmetic prognosis at higher CFL severity and can reduce facial asymmetry occurrence.

A review on polysaccharides mediated electrospun nanofibers for diabetic wound healing: Their current status with regulatory perspective

The current treatment strategies for diabetic wound care provide only moderate degree of effectiveness; hence new and improved therapeutic techniques are in great demand. Diabetic wound healing is a complex physiological process that involves synchronisation of various biological events such as haemostasis, inflammation, and remodelling. Nanomaterials like polymeric nanofibers (NFs) offer a promising approach for the treatment of diabetic wounds and have emerged as viable options for wound management. Electrospinning is a powerful and cost-effective method to fabricate versatile NFs with a wide array of raw materials for different biological applications. The electrospun NFs have unique advantages in the development of wound dressings due to their high specific surface area and porosity. The electrospun NFs possess a unique porous structure and biological function similar to the natural extracellular matrix (ECM), and are known to accelerate wound healing. Compared to traditional dressings, the electrospun NFs are more effective in healing wounds owing to their distinct characteristics, good surface functionalisation, better biocompatibility and biodegradability. This review provides a comprehensive overview of the electrospinning procedure and its operating principle, with special emphasis on the role of electrospun NFs in the treatment of diabetic wounds. This review discusses the present techniques applied in the fabrication of NF dressings, and highlights the future prospects of electrospun NFs in medicinal applications.

Outcomes After Lysis of Adhesions and Dilator Placement for Treatment of Vulvovaginal Agglutination Due to Lichen Planus

OBJECTIVE

The aim of the study is to determine intraoperative and postoperative surgical outcomes for the treatment of vulvovaginal agglutination secondary to lichen planus (LP) following a standard protocol using intraoperative dilator placement and postoperative intravaginal steroid use.

MATERIALS AND METHODS

This was a retrospective chart review of patients who underwent surgical management of vulvovaginal agglutination due to LP following a protocol that included surgical lysis of vulvovaginal adhesions, intraoperative dilator placement and removal 48 hours later, and high-potency intravaginal corticosteroid and regular dilator use thereafter. Demographic and clinical data were abstracted from the medical record and analyzed using descriptive statistics.

RESULTS

Thirty-four patients, with mean age 51.2 ± 11 years and body mass index 32.8 ± 8.5 kg/m 2 , underwent lysis of vulvovaginal adhesions between 1999 and 2021 with 8 different surgeons at a single institution. The mean preoperative, immediate postoperative, and 6-week postoperative vaginal lengths were 2.8 ± 1.8 cm ( n = 18), 8.0 ± 1.9 cm ( n = 21), and 7.9 ± 2.2 cm ( n = 16), respectively. The mean estimated blood loss intraoperatively was 16 ± 15 mL. No patients had a documented surgical site infection or reoperation within 30 days after surgery. Of patients who had it documented ( n = 26), 70% (18/26) reported postoperative sexual activity. Where documented, 100% (18/18) reported preoperative dyspareunia, while 17% (3/18) did postoperatively. Six percent (2/34) had recurrent severe agglutination and 3% (1/34) underwent reoperation.

CONCLUSIONS

Lysis of vulvovaginal adhesions, intraoperative dilator placement, and postoperative intravaginal corticosteroids with dilator use is a safe and effective treatment option to restore vaginal length for those with vulvovaginal LP.