Bioengineered MSCCxcr2 transdifferentiated keratinocyte-like cell-derived organoid potentiates skin regeneration through ERK1/2 and STAT3 signaling in diabetic wound.

Skin regeneration is severely compromised in diabetic foot ulcers. Allogeneic mesenchymal stem cell (MSC) transplantation is limited due to the poor engraftment, mitogenic, and differentiation potential in the harsh wound microenvironment. Thus, to improve the efficacy of cell therapy, the chemokine receptor Cxcr2 was overexpressed in MSCs (MSCCxcr2). CXCL2/CXCR2 axis induction led to the enhanced proliferation of MSCs through the activation of STAT3 and ERK1/2 signaling. Transcriptional upregulation of FGFR2IIIb (KGF Receptor) promoter by the activated STAT3 and ERK1/2 suggested trans-differentiation of MSCs into keratinocytes. These stable MSCCxcr2 in 2D and 3D (spheroid) cell cultures efficiently transdifferentiated into keratinocyte-like cells (KLCs). An in vivo therapeutic potential of MSCCxcr2 transplantation and its keratinocyte-specific cell fate was observed by accelerated skin tissue regeneration in an excisional splinting wound healing murine model of streptozotocin-induced type 1 diabetes. Finally, 3D skin organoids generated using MSCCxcr2-derived KLCs upon grafting in a relatively avascular and non-healing wounds of type 2 diabetic db/db transgenic old mice resulted in a significant enhancement in the rate of wound closure by increased epithelialization (epidermal layer) and endothelialization (dermal layer). Our findings emphasize the therapeutic role of the CXCL2/CXCR2 axis in inducing trans-differentiation of the MSCs toward KLCs through the activation of ERK1/2 and STAT3 signaling and enhanced skin regeneration potential of 3D organoids grafting in chronic diabetic wounds.

Analysis of risk factors related to chronic non-healing wound infection and the construction of a clinical prediction model.

This study is aimed to analyse the risk factors associated with chronic non-healing wound infections, establish a clinical prediction model, and validate its performance. Clinical data were retrospectively collected from 260 patients with chronic non-healing wounds treated in the plastic surgery ward of Shanxi Provincial People's Hospital between January 2022 and December 2023 who met the inclusion criteria. Risk factors were analysed, and a clinical prediction model was constructed using both single and multifactor logistic regression analyses to determine the factors associated with chronic non-healing wound infections. The model's discrimination and calibration were assessed via the concordance index (C-index), receiver operating characteristic (ROC) curve and calibration curve. Multivariate logistic regression analysis identified several independent risk factors for chronic non-healing wound infection: long-term smoking (odds ratio [OR]: 4.122, 95% CI: 3.412-5.312, p < 0.05), history of diabetes (OR: 3.213, 95% CI: 2.867-4.521, p < 0.05), elevated C-reactive protein (OR: 2.981, 95% CI: 2.312-3.579, p < 0.05), elevated procalcitonin (OR: 2.253, 95% CI: 1.893-3.412, p < 0.05) and reduced albumin (OR: 1.892, 95% CI: 1.322-3.112, p < 0.05). The clinical prediction model's C-index was 0.762, with the corrected C-index from internal validation using the bootstrap method being 0.747. The ROC curve indicated an area under the curve (AUC) of 0.762 (95% CI: 0.702-0.822). Both the AUC and C-indexes ranged between 0.7 and 0.9, suggesting moderate-to-good predictive accuracy. The calibration chart demonstrated a good fit between the model's calibration curve and the ideal curve. Long-term smoking, diabetes, elevated C-reactive protein, elevated procalcitonin and reduced albumin are confirmed as independent risk factors for bacterial infection in patients with chronic non-healing wounds. The clinical prediction model based on these factors shows robust performance and substantial predictive value.

Teleconsulting in wound care: Connecting the primary care to the wound specialist reduces unnecessary referrals.

In the Netherlands the primary care (General Practitioner or homecare nurse) encounter a variety of wounds ranging from traumatic to diabetic foot ulcers. According to a recent study 82.4% of the patients with a wound can be treated in a primary setting with the GP as medical supervisor. The remaining 17.6% of patients need more extensive care including advice by a specialised doctor, diagnosis and treatment. Prompt analyses and treatment of underlying causes by specialised doctors in a multidisciplinary setting is necessary for treating patients with complicated wound. This article describes the impact of Electronic Health Consultation on all wounds treated in the primary care. And describes the effect on the duration until referral to the hospital and the influence on the amount of unnecessary referrals to the hospital. All data was collected prospectively from June 2020 until October 2021. The study involved a process where primary care could seek advice from a Wound Physician at the Alrijne Wound Centre through a specialised Electronic Health Consultation. A total of 118 patients were analysed. 41/118 (34.7%) patients required a physical consultation with analysis and treatment in the hospital, after teleconsultation. The remaining 77/118 (65.3%) could be treated in primary care after Electronic Health Consultation. The mean duration of wound existence until Electronic Health Consultation was 39.3 days (range 5-271, SD: 38.5). 3/41 (7.3%) of the referrals were unnecessary. Electronic Health Consultation serves as a valuable and efficient tool for enhancing wound care, ultimately contributing to improved patient management and resource allocation within the healthcare system. This article describes the impact of Electronic Health Consultation on all wounds treated in the primary care and the influence on the duration until referral to the hospital and the influence on the amount of unnecessary referrals to the hospital.

Dehydrated human amnion/chorion membrane allograft with spongy layer to significantly improve the outcome of chronic non-healing wounds.

We investigated the healing effect of a new dehydrated amnion/chorion membrane with a spongy layer over a 30-month period in 32 patients with 53 chronic non-healing wounds of different aetiologies. Wounds with <40% surface reduction after 4 weeks of best wound treatment underwent weekly allograft application by a certified wound specialist based on national guidelines and a standardised protocol until complete healing or definite treatment interruption. The main outcome measure was the percentage of wound surface reduction from baseline calculated using digital planimetry follow-up photographs. Overall, 38 (71.7%) wounds presented a favourable outcome (70%-100% area reduction), with 35 (66%) completely healing over a median time of 77 days (range 29-350 days). Favourable outcomes were observed in 75% of traumatic wounds, surgical wounds, venous leg ulcers and pressure injuries, as well as in 50% of ischaemic wounds. Wounds being present <12 months were significantly more likely to have a favourable outcome than more long-standing wounds (χ2 = 7.799; p = 0.005; OR = 3.378; 95% CI, 1.410-8.092). Thus, treatment with dehydrated amnion/chorion membrane with a spongy layer improves the outcome of non-healing wounds of different aetiologies and, therefore, has to be considered early in the management of refractory wounds.

Efficiency assessment of irrigation as an alternative method for improving the regenerative potential of non-healing wounds.

The application of mesenchymal stem/stromal cells (MSC) in regenerative medicine offers hope for the effective treatment of incurable or difficult-to-heal diseases. However, it requires the development of unified protocols for both safe and efficient cell acquisition and clinical usage. The therapeutic effect of fat grafts (containing stem cells) in non-healing wounds has been discussed in previous studies, although the application requires local or general anaesthesia. The treatment of MSC derived from adipose tissue (ASC) could be a less invasive method, and efficient delivery could lead to more favourable outcomes, which should encourage clinicians to use such therapeutic approaches more frequently. Therefore, the aim of this study was to optimise the methods of ASC isolation, culture and administration while maintaining their high survival, proliferation and colonisation potential. The ASC were isolated by an enzymatic method and were characterised according to International Society for Cellular Therapy and International Federation for Adipose Therapeutics and Science guidelines. To assess the opportunity to obtain a sufficient number of cells for transplantation, long-term cell cultures in two oxygen concentrations (5% vs. 21%) were conducted. For these cultures, the population doubling time, the cumulative time for cell population doublings and the rate of cell senescence were estimated. In a developed and pre-defined protocol, ASC can be efficiently cultured at physiological oxygen concentrations (5%), which leads to faster proliferation and slower cell senescence. Subsequently, to select the optimal and minimally invasive methods of ASC transplantation, direct cell application with an irrigator or with skin dressings was analysed. Our results confirmed that both the presented methods of cell application allow for the safe delivery of isolated ASC into wounds without losing their vitality. Cells propagated in the described conditions and applied in non-invasive cell application (with an irrigation system and dressings) to treat chronic wounds can be a potential alternative or supplement to more invasive clinical approaches.

The healing dynamics of non-healing wounds using cryo-preserved amniotic membrane.

We evaluated the effect of the application of cryo-preserved amniotic membrane on the healing of 26 non-healing wounds (18 patients) with varying aetiologies and baseline sizes (average of 15.4 cm2 ), which had resisted the standard of care treatment for 6 to 456 weeks (average 88.8 weeks). Based on their average general responses to the application of cryo-preserved AM, we could differentiate three wound groups. The first healed group was characterised by complete healing (100% wound closure, maximum treatment period 38 weeks) and represented 62% of treated wounds. The wound area reduction of at least 50% was reached for all wounds in this group within the first 10 weeks of treatment. Exactly 19% of the studied wounds responded partially to the treatment (partially healed group), reaching less than 25% of closure in the first 10 weeks and 90% at maximum for extended treatment period (up to 78 weeks). The remaining 19% of treated wounds did not show any reaction to the AM application (unhealed defects). The three groups have different profiles of wound area reduction, which can be used as a guideline in predicting the healing prognosis of non-healing wounds treated with a cryo-preserved amniotic membrane.

Assessment of frailty in elderly patients attending a multidisciplinary wound care centre: a cohort study.

BACKGROUND: The incidence of frailty and non-healing wounds increases with patients' age. Knowledge of the relationship between frailty and wound healing progress is greatly lacking. METHODS: The aim of this study is to characterize the degree of frailty in elderly patients attending a multidisciplinary wound care centres (MWCC). Additionally, we seek to assess the impact of frailty on the wound healing rate and wound healing time. An open cohort study was conducted on 51 consecutive patients aged > 70 years treated for wounds at an MWCC of an intermediate care hospital. The frailty score was determined according to the Frail-VIG index. Data were collected through patient questionnaires at the beginning of the study, and at 6 months or upon wound healing. Wounds were followed up every 2 weeks. To analyse the relationship between two variables was used the Chi-square test and Student's or the ANOVA model. The t-test for paired data was used to analyse the evolution of the frailty index during follow-up. RESULTS: A total of 51 consecutive patients were included (aged 81.1 ± 6.1 years). Frailty prevalence was 74.5% according to the Frail-VIG index (47.1% mildly frail, 19.6% moderately frail, and 7.8% severely frail). Wounds healed in 69.6% of cases at 6 months. The frailty index (FI) was higher in patients with non-healing wounds in comparison with patients with healing wounds (IF 0.31 ± 0.15 vs IF 0.24 ± 0.11, p = 0.043). A strong correlation between FI and wound healing results was observed in patients with non-venous ulcers (FI 0.37 ± 0.13 vs FI 0.27 ± 0.10, p = 0.015). However, no correlation was observed in patients with venous ulcers (FI 0.17 ± 0.09 vs FI 0.19 ± 0.09, p = 0.637). Wound healing rate is statically significantly higher in non-frail patients (8.9% wound reduction/day, P25-P75 3.34-18.3%/day;AQ6 p = 0.044) in comparison with frail patients (3.26% wound reduction/day, P25-P75 0.8-8.8%/day). CONCLUSION: Frailty is prevalent in elderly patients treated at an MWCC. Frailty degree is correlated with wound healing results and wound healing time.

A Beginner's Introduction to Skin Stem Cells and Wound Healing.

The primary function of the skin is that of a physical barrier against the environment and diverse pathogens; therefore, its integrity is essential for survival. Skin regeneration depends on multiple stem cell compartments within the epidermis, which, despite their different transcriptional and proliferative capacity, as well as different anatomical location, fall under the general term of skin stem cells (SSCs). Skin wounds can normally heal without problem; however, some diseases or extensive damage may delay or prevent healing. Non-healing wounds represent a serious and life-threatening scenario that may require advanced therapeutic strategies. In this regard, increased focus has been directed at SSCs and their role in wound healing, although emerging therapeutical approaches are considering the use of other stem cells instead, such as mesenchymal stem cells (MSCs). Given its extensive and broad nature, this review supplies newcomers with an introduction to SSCs, wound healing, and therapeutic strategies for skin regeneration, thus familiarizing the reader with the subject in preparation for future in depth reading.

Wound Repair and Extremely Low Frequency-Electromagnetic Field: Insight from In Vitro Study and Potential Clinical Application.

Wound healing is a complex, staged process. It involves extensive communication between the different cellular constituents of various compartments of the skin and its extracellular matrix (ECM). Different signaling pathways are determined by a mutual influence on each other, resulting in a dynamic and complex crosstalk. It consists of various dynamic processes including a series of overlapping phases: hemostasis, inflammation response, new tissue formation, and tissue remodeling. Interruption or deregulation of one or more of these phases may lead to non-healing (chronic) wounds. The most important factor among local and systemic exogenous factors leading to a chronic wound is infection with a biofilm presence. In the last few years, an increasing number of reports have evaluated the effects of extremely low frequency (ELF) electromagnetic fields (EMFs) on tissue repair. Each experimental result comes from a single element of this complex process. An interaction between ELF-EMFs and healing has shown to effectively modulate inflammation, protease matrix rearrangement, neo-angiogenesis, senescence, stem-cell proliferation, and epithelialization. These effects are strictly related to the time of exposure, waveform, frequency, and amplitude. In this review, we focus on the effect of ELF-EMFs on different wound healing phases.

Secretome of Adipose Tissue-Derived Stem Cells (ASCs) as a Novel Trend in Chronic Non-Healing Wounds: An Overview of Experimental In Vitro and In Vivo Studies and Methodological Variables.

Wound healing is a complex process with a linear development that involves many actors in a multistep timeline commonly divided into four stages: Hemostasis, inflammation, proliferation, and remodeling. Chronic non-healing wounds fail to progress beyond the inflammatory phase, thus precluding the next steps and, ultimately, wound repair. Many intrinsic or extrinsic factors may contribute to such an occurrence, including patient health conditions, age-related diseases, metabolic deficiencies, advanced age, mechanical pressure, and infections. Great interest is being focused on the adipose tissue-derived stem cell's (ASC) paracrine activity for its potential therapeutic impact on chronic non-healing wounds. In this review, we summarize the results of in vitro and in vivo experimental studies on the pro-wound healing effects of ASC-secretome and/or extracellular vesicles (EVs). To define an overall picture of the available literature data, experimental conditions and applied methodologies are described as well as the in vitro and in vivo models chosen in the reported studies. Even if a comparative analysis of the results obtained by the different groups is challenging due to the large variability of experimental conditions, the available findings are undoubtedly encouraging and fully support the use of cell-free therapies for the treatment of chronic non-healing wounds.

Healing Tough Wounds Using Topical Oxygen Therapy During Hemodialysis Sessions.

Topical oxygen therapy (TOT) is used widely in the treatment of difficult-to-heal arterial and venous ulcers in patients with peripheral vascular disease (PVD), diabetic ulcers, and lower extremity venous insufficiency. Successful TOT relies on supplying 100% oxygen at 1.04 atmospheres to the ulcered area. In principle, TOT allows a rapid proliferation of new epithelium over the ulcer. This article describes two case studies with successful wound healing as a result of using this clinical method during hemodialysis sessions.

Chronic non-healing wounds in geriatrics.

Chronic non-healing wounds represent a frequent comorbidity among geriatric patients. Non-healing wounds increase patients morbidity and mortality and significantly decrease their quality of life. Prognosis of these wounds depends on etiology, overall health condition of the patient and also on the proper treatment. In this review we outline the classification of non-healing wounds and focus in more detail on the most frequent types: venous and arterial leg ulcers, diabetic foot syndrome and pressure ulcers. Key words: diabetic foot ulcers - chronic venous insufficiency - chronic wounds - limb ischemia - non-healing wounds - pressure ulcers.

Management of Fournier's gangrene non-healing wounds by autologous skin micrograft biotechnology: a new technique.

Fournier's gangrene is an acute bacterial infection producing necrosis of the perineum and external genitalia that generally affects elderly men. Although skin grafts and flaps are the standard procedure for reconstruction, sometimes wounds can become chronic. Rigenera Protocol is a new technique based on autologous skin micrografts that reactivates and supports wound healing. A 40-year-old male with Fournier's gangrene, due to a rectal microperforation following diarrhoea, was treated with surgical debridement, negative pressure wound therapy and subsequently coverage with skin grafts. He developed non-healing wounds treated by Rigenera protocol after two months of advanced wound dressings. This technique is based on skin micrografts obtained by mechanical dermal disgregation to provide mesenchymal stem cells and extracellular matrix to the wound. The suspension injected into the wound triggers reactivation of healing without significant residual scarring on both donor site and treated area. Non-healing wounds were reduced by 15% at day 7 and by 50% after 30 days. Wounds completely healed after seventy days. The regenerated tissue appeared closer to skin graft than to scar tissue. This report shows how the use of skin micrografts through Rigenera protocol can be a useful method to reactivate wound healing resulting from Fournier's gangrene, with no discomfort for patient in a practical, safe and easy way.

Evaluating the effect of a haemoglobin spray on size reduction in chronic DFUs.

AIM: The aim of this multi-centre observational evaluation was to assess the percentage reduction in wound area of non-healing diabetic foot ulcers (DFUs), treated with Granulox haemoglobin spray over a 4-week period. Secondary outcome parameters--for example, adverse events, patient acceptability and ease of use--were also recorded. METHOD: After a run-in-period (2 weeks for existing patients and 4 weeks for new patients) to determine if the wounds were non-healing despite receiving local best practice, patients whose foot ulcers had decreased in size by < 20% were then entered into the evaluation. A sample of 17 patients (4 females and 13 males), comprising 4 with type 1 and 13 with type 2 diabetes, with a total of 20 DFUs, met the inclusion criteria. These data were collected from six sites across the UK. RESULTS: There was an overall positive reduction in size in 15 of the wounds, equating to a mean reduction of 53.8% (standard deviation (SD): 26.6; range: 11.9-100%). One participant, with two ulcers, had to be withdrawn due to infection. All clinicians and participants found the product easy to use. CONCLUSION: The addition of a topical oxygenation therapy in this cohort of non-healing DFUs showed reduction in wound surface area and progression to healing. The product was also found to be acceptable and very easy to use by both participants and clinicians.

Non-healing foot ulcers in diabetic patients: general and local interfering conditions and management options with advanced wound dressings.

Medical knowledge about wound management has improved as recent studies have investigated the healing process and its biochemical background. Despite this, foot ulcers remain an important clinical problem, often resulting in costly, prolonged treatment. A non-healing ulcer is also a strong risk factor for major amputation. Many factors can interfere with wound healing, including the patient's general health status (i.e., nutritional condition indicated by albumin levels) or drugs such as steroids that can interfere with normal healing. Diabetic complications (i.e., renal insufficiency) may delay healing and account for higher amputation rates observed in diabetic patients under dialysis treatment. Wound environment (e.g., presence of neuropathy, ischaemia, and infection) may significantly influence healing by interfering with the physiological healing cascade and adding local release of factors that may worsen the wound. The timely and well-orchestrated release of factors regulating the healing process, observed in acute wounds, is impaired in non-healing wounds that are blocked in a chronic inflammatory phase without progressing to healing. This chronic phase is characterised by elevated protease activity (EPA) of metalloproteinases (MMPs) and serine proteases (e.g., human neutrophil elastase) that interfere with collagen synthesis, as well as growth factor release and action. EPA (mainly MMP 9, MMP-8 and elastase) and inflammatory factors present in the wound bed (such as IL-1, IL-6, and TNFa) account for the catabolic state of non-healing ulcers. The availability of wound dressings that modulate EPA has added new therapeutic options for treating non-healing ulcers. The literature confirms advantages obtained by reducing protease activity in the wound bed, with better outcomes achieved by using these dressings compared with traditional ones. New technologies also allow a physician to know the status of the wound bed environment, particularly EPA, in a clinical setting. These may be helpful in guiding a clinician's options in treating very difficult-to-heal ulcers.

Going green: using a bio-cellulose membrane for patients with chronic non-healing wounds.

A 20-patient evaluation was undertaken on the most chronic non-healing wounds that had been present in excess of 6 months. Patients were treated with a biotechnology dressing that is provided in a mesh and gel combination. Eighteen of out 20 patients went on to heal. Cost effectiveness examined the cost associated with maintaining non-healing wounds where all alternative therapies had failed. Nursing time both in outpatients and home visits were included. A wide variety of secondary dressings were applied according to clinical preference as the new dressings are designed as a direct wound contact mesh. This is a very new concept to wound care, with initial unit cost being high, but the possibilities of natural plant extracts that can mimic collagen synthesis is exciting. Both the staff and patients have seen a marked improvement, with up to date no recurrence. Further studies need to be undertaken to establish if these early findings are repeatable.

Antimicrobials and Non-Healing Wounds. Evidence, controversies and suggestions-key messages.

This article constitutes an extraction of key messages originally presented in the Document: Antimicrobials and Non-Healing Wounds. Evidence, controversies and suggestions written by the European Wound Management Association (EWMA), and originally published by the Journal of Wound Care in 2013. All sections are shortened and some not included. For further details please refer to in the original document which can be downloaded via www.ewma.org .

Management of non-healable or maintenance wounds with topical povidone iodine.

Although complete healing may appear to be the logical goal for most patients and clinicians, some wounds do not have the potential to heal due to a number of factors such as inadequate vasculature, coexisting medical conditions and medications that prohibit the healing process. Local management of wounds that are considered to have poor potential for healing remains elusive. The purpose of this article is to review the evidence that supports the use of topical antiseptic agents in non-healable wounds. Retrospective chart audit was conducted to evaluate the use of povidone iodine in the management of wounds that were deemed to have poor healing potential.

The NLRP3 inflammasome in burns: a novel potential therapeutic target.

Burns are an underestimated serious injury negatively impacting survivors physically, psychologically and economically, and thus are a considerable public health burden. Despite significant advancements in burn treatment, many burns still do not heal or develop serious complications/sequelae. The nucleotide-binding oligomerization domain-like receptors (NLRs) family pyrin domain-containing 3 (NLRP3) inflammasome is a critical regulator of wound healing, including burn wound healing. A better understanding of the pathophysiological mechanism underlying the healing of burn wounds may help find optimal therapeutic targets to promote the healing of burn wounds, reduce complications/sequelae following burn, and maximize the restoration of structure and function of burn skin. This review aimed to summarize current understanding of the roles and regulatory mechanisms of the NLRP3 inflammasome in burn wound healing, as well as the preclinical studies of the involvement of NLRP3 inhibitors in burn treatment, highlighting the potential application of NLRP3-targeted therapy in burn wounds.

Assessment, prevention and management of skin tears in older people.

Skin tears are common injuries that result from mechanical forces. Older people with fragile skin are at greater risk of this type of wound. They are usually categorised as acute wounds that typically heal in 7-21 days but the healing process can be disrupted, leading to chronic, non-healing wounds. They have the potential to compromise quality of life and disrupt daily activities, so it is important to identify risk factors and implement prevention strategies for those at risk. An interdisciplinary approach has a pivotal role in promptly and precisely identifying skin tears, and the use of evidence-based interventions for efficient skin damage management can enhance the recovery process. This article adopts a case study approach to explore the prevention, evaluation and treatment of skin tears, using the case of an individual living with a skin tear in a community setting.