Use of platelet-rich plasma in deep second- and third-degree burns

Comparison of the effects of platelet-rich plasma and platelet-rich fibrin on the healing process of a rat's mucosal wound

Due to the problems associated with the use of PRP, a platelet concentrates without coagulation factors, called platelet-rich fibrin (PRF), has been developed that, in addition to tissue regeneration and wound healing, contains more white blood cells (WBCs), which are important in the wound healing process. In this study, the effect of these two platelet-rich plasmas on the thickness of the epithelium, the number of blood vessels and fibroblasts, and wound area were measured in two groups of PRP and PRF and at different periods. We divided the rats into three groups: the control group, the group receiving PRP, and the group receiving PRF. The results showed a significant difference in the number of fibroblasts, wound area, thickness of epithelium, and number of vessels in all three groups. Based on the results, the use of PRP and PRF in wounds can accelerate the formation of epithelium, create better and more blood vessels, create a platform for the migration and formation of fibroblast cells, and facilitate faster wound closure. Also, comparing PRP and PRF, it can be concluded that, finally, PRF acts better than PRP in epithelialization.

Understanding the ideal wound healing mechanistic behavior using in silico modelling perspectives: A review

Complexity of the entire body precludes an accurate assessment of the specific contributions of tissues or cells during the healing process, which might be expensive and time consuming. Because of this, controlling the wound's size, depth, and dimensions may be challenging, and there is not yet an efficient and reliable chronic wound model representation. Furthermore, given the inherent challenges associated with conducting non-invasive in vivo investigations, it becomes peremptory to explore alternative methodologies for studying wound healing. In this context, biologically-realistic mathematical and computational models emerge as a valuable framework that can effectively address this need. Therefore, it might improve our approach to understanding the process at its core. This article will examines all facets of wound healing, including the kinds, pathways, and most current developments in wound treatment worldwide, particularly in silico modelling utilizing both mathematical and structure-based modelling techniques. It may be helpful to identify the crucial traits through the feedback loop of computer models and experimental investigations in order to build innovative therapies to cure wounds. Hence the effectiveness of personalised medicine and more targeted therapy in the healing of wounds may be enhanced by this interdisciplinary expertise.

Topical Synthetic Platelets Loaded With Gentamicin Decrease Bacteria in Deep Partial-Thickness Burns

INTRODUCTION

Prolonged inflammation and infection in burns may cause inadequate healing. Platelet granules contain anti-inflammatory mediators that impact wound healing. Synthetic platelets (SPs) avoid portability and storage difficulties of natural platelets and can be loaded with bioactive agents. We evaluated wound healing outcomes in deep partial-thickness (DPT) burns treated topically with SP loaded with antibiotics.

MATERIALS AND METHODS

Thirty DPT burns were created on the dorsum of two Red Duroc hybrid pigs. Six wounds were randomized into five groups: SP alone, SP loaded with gentamicin vesicles, SP with gentamicin mixture, vehicle control (saline), or dry gauze. Wounds were assessed from postburn days 3-90. Primary outcome was re-epithelialization percentage at postburn day 28. Secondary outcomes included wound contraction percentage, superficial blood flow relative to normal skin controls, and bacterial load score.

RESULTS

Results showed that re-epithelialization with the standard of care (SOC) was 98%, SP alone measured 100%, SP loaded with gentamicin vesicles was 100%, and SP with gentamicin mixture was 100%. Wound contraction was 5.7% in the SOC and was ∼10% in both the SP loaded with gentamicin vesicles and SP with gentamicin mixture groups. Superficial blood flow in the SOC was 102.5%, SP alone was 170%, the SP loaded was 155%, and gentamicin mixture 162.5%. Bacterial load score in the SOC was 2.2/5.0 and was significantly less at 0.8/5.0 in SP loaded with gentamicin vesicles (P > 0.05). SP and gentamicin mixture scored 2.7 and 2.3/5.0.

CONCLUSIONS

Topical SP treatment did not significantly improve outcomes. However, SP loaded with gentamicin-infused vesicles decreased bacterial load.

Management of Facial Second-Degree Burns with Nanocellulose-Based Dressing: A Case Series and Systematic Review

Previous studies have evaluated the effectiveness of bacterial nanocellulose (BNC) for the treatment of thermal injuries, but the synergic effect of platelet-rich plasma (PRP) with BNC-based dressing for burns still requires further investigation. Herein, we evaluated the effectiveness of BNC dressings in the management of facial burns using PRP. Patients with second-degree facial burns were treated with BNC-based wound dressings after debridement. The burn's depth and epithelialization were evaluated by clinical assessment. Besides using the dressings, we injected PRP subcutaneously into the left-hemifacial burns. The right hemiface was only treated with the dressings. Scar quality was assessed using the Patient and Observer Scar Assessment Scale (POSAS). Eight patients were included with superficial second-degree burns in 75% of the cases and deep second-degree burns in 25%. Overall, dressings were placed 3.25 days after the initial insult. None of the patients presented with complications after dressing placement. Dressing changes were not required, and no further surgical management was necessary. The mean time for epithelialization was 11.4 days. During subgroup analysis, we did not find a significant difference in the epithelialization time when comparing BNC-based dressings (11.8 days) to BNC-based dressings + PRP (11 days, p = 0.429). The mean POSAS scores from a patient (17 vs. 12.3, p = 0.242) and surgeon (13.5 vs. 11.3, p = 0.26) standpoint were not significantly different using BNC-based dressings versus BNC-based dressings + PRP. Nanocellulose-based dressings are effective to treat second-degree facial burns. It enhances reepithelialization with optimal esthetic outcomes with or without PRP.

Autologous Platelet and Extracellular Vesicle-Rich Plasma as Therapeutic Fluid: A Review

The preparation of autologous platelet and extracellular vesicle-rich plasma (PVRP) has been explored in many medical fields with the aim to benefit from its healing potential. In parallel, efforts are being invested to understand the function and dynamics of PVRP that is complex in its composition and interactions. Some clinical evidence reveals beneficial effects of PVRP, while some report that there were no effects. To optimize the preparation methods, functions and mechanisms of PVRP, its constituents should be better understood. With the intention to promote further studies of autologous therapeutic PVRP, we performed a review on some topics regarding PVRP composition, harvesting, assessment and preservation, and also on clinical experience following PVRP application in humans and animals. Besides the acknowledged actions of platelets, leukocytes and different molecules, we focus on extracellular vesicles that were found abundant in PVRP.

Risk factors for diabetic foot ulcers mortality and novel negative pressure combined with platelet-rich plasma therapy in the treatment of diabetic foot ulcers

The purpose of this study was to assess the risk factors for morbidity and mortality of diabetic foot ulcers (DFUs). For the treatment of diabetic foot ulcers, negative pressure wound therapy (NPWT) combined with platelet-rich plasma-fibrin glue (PRP) was also investigated. There were 653 patients in the diabetic foot ulcer group and 510 patients in the diabetic patients without foot ulceration (NFU) group, for a total of 1163 patients in the study samples after individuals without follow-up were excluded. The patients were randomized into two groups: the negative pressure wound therapy group and the negative pressure wound therapy combined with the PRP group. The findings of the univariate analysis revealed the blood indicators for predicting diabetic foot ulcer morbidity risk factors, such as C-reactive protein, albumin, creatinine, alkaline phosphatase, procalcitonin, platelets, 25-hydroxyvitamin D, β-2-microglobulin, monocyte ratio, low-density protein cholesterol (LDL), triglyceride, alanine aminotransferase (ALT), aminotransferase (AST), creatine kinase (CK) and total cholesterol. Using logistic regression analysis revealed only albumin and age to be independent predictors of diabetic foot ulcer mortality. Our study also revealed that, compared to negative pressure wound therapy alone, negative pressure wound therapy combined with PRP accelerated wound healing and reduced the mortality rate. According to the findings of this pilot study, new risk factors for diabetic foot ulcer morbidity and mortality have been found, and negative pressure wound therapy combined with PRP therapy may provide the first information that it is an effective adjunct treatment for diabetic foot ulcers.

The effects of mesenchymal stromal cells and platelet-rich plasma treatments on cutaneous wound healing

Cellular therapy and platelet-rich plasma (PRP) have been used as a treatment for skin wounds. Previous evidence has shown that mesenchymal stromal cells (MSC) may improve skin wound healing. In contrast, contradictory effects have been reported by using PRP treatment on skin wound healing. However, there is evidence that PRP constitutes an excellent scaffold for tissue engineering. In this work, we aim to study the effect of MSC on skin wound healing. We used an experimental murine model of full-thickness wounds. Wounds were treated with human bone marrow-MSC contained in a PRP clot. Untreated or PRP-treated wounds were used as controls. Wound healing was evaluated by macroscopic observation and histological analysis at day 7 post-wounding. Immunohistochemical studies were performed to detect the presence of epithelial progenitor cells (EPC) and the expression of basic fibroblast growth factor (bFGF). MSC/PRP implantation induced a significant wound closure and re-epithelialization as compared with the controls. Increase of CD34⁺ cells and bFGF was observed in the wounds treated with MSC/PRP. Our results show that MSC included in PRP clot induce cutaneous wound repair by promoting re-epithelialization, migration of EPC and expression of bFGF. PRP alone does not exert a significant effect on wound healing. Our results support the possible clinical use of MSC in PRP scaffold as potential treatment of skin wounds.

Pharmaceutical Prophylaxis of Scarring with Emphasis on Burns: A Review of Preclinical and Clinical Studies

Significance: The worldwide estimate of burns requiring medical attention each year is 11 million. Each year in the United States, ∼486,000 burn injuries receive medical attention, including 40,000 hospitalizations. Scars resulting from burns can be disfiguring and impair functions. The development of prophylactic drugs for cutaneous scarring could improve the outcomes for burns, traumatic lacerations (>6 million/year treated in U.S. emergency rooms), and surgical incisions (∼250 million/year worldwide). Antiscar pharmaceuticals have been estimated to have a market of $12 billion. Recent Advances: Many small molecules, cells, proteins/polypeptides, and nucleic acids have mitigated scarring in animal studies and clinical trials, but none have received Food and Drug Administration (FDA) approval yet. Critical Issues: The development of antiscar pharmaceuticals involves the identification of the proper dose, frequency of application, and window of administration postwounding for the indicated wound. Risks of infection and impaired healing must be considered. Scar outcome needs to be evaluated after scars have matured. Future Directions: Once treatments have demonstrated safety and efficacy in rodent and/or rabbit and porcine wound models, human testing can begin, such as on artificially created wounds on healthy subjects and on bilateral-surgical wounds, comparing treatments versus vehicle controls on intrapatient-matched wounds, before testing on separate cohorts of patients. Given the progress made in the past 20 years, FDA-approved drugs for improving scar outcomes may be expected.

Emerging treatment strategies in wound care

Wound healing is a complex process in tissue regeneration through which the body responds to the dissipated cells as a result of any kind of severe injury. Diabetic and non-healing wounds are considered an unmet clinical need. Currently, different strategic approaches are widely used in the treatment of acute and chronic wounds which include, but are not limited to, tissue transplantation, cell therapy and wound dressings, and the use of an instrument. A large number of literatures have been published on this topic; however, the most effective clinical treatment remains a challenge. The wound dressing involves the use of a scaffold, usually using biomaterials for the delivery of medication, autologous stem cells, or growth factors from the blood. Antibacterial and anti-inflammatory drugs are also used to stop the infection as well as accelerate wound healing. With an increase in the ageing population leading to diabetes and associated cutaneous wounds, there is a great need to improve the current treatment strategies. This research critically reviews the current advancement in the therapeutic and clinical approaches for wound healing and tissue regeneration. The results of recent clinical trials suggest that the use of modern dressings and skin substitutes is the easiest, most accessible, and most cost-effective way to treat chronic wounds with advances in materials science such as graphene as 3D scaffold and biomolecules hold significant promise. The annual market value for successful wound treatment exceeds over $50 billion US dollars, and this will encourage industries as well as academics to investigate the application of emerging smart materials for modern dressings and skin substitutes for wound therapy.

Healing Mechanisms in Cutaneous Wounds: Tipping the Balance

Acute and chronic cutaneous wounds pose a significant health and economic burden. Cutaneous wound healing is a complex process that occurs in four distinct, yet overlapping, highly coordinated stages: hemostasis, inflammation, proliferation, and remodeling. Postnatal wound healing is reparative, which can lead to the formation of scar tissue. Regenerative wound healing occurs during fetal development and in restricted postnatal tissues. This process can restore the wound to an uninjured state by producing new skin cells from stem cell reservoirs, resulting in healing with minimal or no scarring. Focusing on the pathophysiology of acute burn wounds, this review highlights reparative and regenerative healing mechanisms (including the role of cells, signaling molecules, and the extracellular matrix) and discusses how components of regenerative healing are being used to drive the development of novel approaches and therapeutics aimed at improving clinical outcomes. Important components of regenerative healing, such as stem cells, growth factors, and decellularized dermal matrices, are all being evaluated to recapitulate more closely the natural regenerative healing process.

The Role of Autologous PRP on Deep Partial-Thickness Burn Wound Healing in Bama Pigs

In this study, we aimed to evaluate the therapeutic effects of autologous platelet-rich plasma (PRP) on deep partial-thickness burns in Bama pigs. Deep partial-thickness burn wounds were created on the back of Bama pigs. The reepithelialization time was compared between the PRP and control groups. The mean score of Ki67 (+) cells and α-SMA (+) vessels, the mean thickness of epidermis and dermis of the healing wounds were determined via H&E staining and immunohistochemical assay. The levels of the growth factors epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were examined by ELISA. Our data showed that the time to wound reepithelialization was shorter in the PRP group compared with the control group. The thickness of the epidermis was larger in the PRP group compared with the control group. On the 7th and 14th days after the treatment, the mean score of Ki67 (+) cells and α-SMA (+) vessels were higher in the PRP group compared with the control group. The PRP group showed higher levels of growth factors (EGF, bFGF, and VEGF) compared with the control group by ELISA. The results indicated that PRP could improve wound healing process of deep partial-thickness burns in Bama pigs. The PRP increased the thickness of epidermis of the healed wounds, cell proliferation, and angiogenesis. We demonstrated that applying PRP had a greater potential for the treatment of deep partial-thickness burns.

An Autologous Protein-Based Topical Ointment for Hard-to-Heal Skin Wounds: A Multiple Case Series

BACKGROUND

There is increasing evidence regarding the wound healing potential of platelet-derived autologous by-products. We provide preliminary data regarding the use of a new plasma rich in growth factors-derived autologous topical ointment for the management of hard-to-heal wounds.

CASES

Four patients suffering from difficult-to-heal wounds were treated with the autologous ointment. Within 2 to 8 weeks, all wounds healed completely with no signs of infection or functional impairment of the affected limbs. No adverse events were reported.

CONCLUSION

Randomized and controlled trials are needed to determine the clinical efficacy of the autologous ointment. Nevertheless, results from this multiple case series indicate that this approach may be useful for accelerating the re-epithelization of difficult-to-heal wounds.

Investigation into antibacterial and wound healing properties of platelets lysate against Acinetobacter baumannii and Klebsiella pneumoniae burn wound infections

Background and aim

Treatment of burn wound infections has become a global challenge due to the spread of multidrug-resistant bacteria; therefore, the development of new treatment options for the mentioned infections is essential. Platelets have drawn much attention for this purpose because they are a safe and cost-effective source of different antimicrobial peptides and growth factors. The present study evaluated antibacterial effects and wound healing properties of Platelet-derived Biomaterial (PdB) against Acinetobacter baumannii and Klebsiella pneumoniae burn wound infections.

Methods

PdB was prepared through the freezing and thawing process and then, in vitro antibacterial effect was determined by disk diffusion and broth microdilution methods. Afterward, burn wound was inflicted on 56 rats, infected with both bacteria, and topical administration was performed to evaluate antibacterial effects and wound healing properties of PdB.

Results

In vitro results showed that PdB inhibited the growth of A. baumannii in the highest dose (0.5), while we did not detect any inhibitory effects against K. pneumoniae. By contrast, PdB significantly inhibited the growth of bacteria in treated animal wounds compared to the control groups (P value < 0.05). Macroscopic assessments pointed to the significant enhancement of wound closure in the treated animals. In addition, histopathological examination demonstrated that treatment of rats with PdB led to a considerable increase in re-epithelialization and attenuated the formation of granulation tissue (P value < 0.05).

Conclusion

The use of topical PdB is an attractive strategy for treating A. baumannii and K. pneumoniae burn wound infections because it inhibits bacterial growth and promotes wound healing properties.

Diverse Treatments for Deep Burn Wounds: A Case Report

ABSTRACT

Patients with extensive deep burns usually experience infections and organ dysfunction. Proactive and effective wound repair is key to treatment. If large wounds remain open, systemic infection and multiple organ dysfunction syndrome can occur, threatening the lives of patients. Current wound repair methods include skin grafts, flap repair, negative-pressure wound therapy, and cellular and/or tissue-based products. For deep, complex burn wounds, a single form of treatment is usually ineffective. This article reports a rare case of burn wound repair. The patient was burned by a charcoal flame on multiple parts of his body after carbon monoxide poisoning. Pneumothorax and acute renal failure occurred after the injury, accompanied by multiple osteonecroses of the trunk and lower limbs. A multidisciplinary team formulated an individualized treatment plan; the diverse treatments included closed chest drainage, continuous renal replacement therapy, infection control, analgesia, wound debridement, negative-pressure wound therapy, cellular and/or tissue-based products, autologous dermal scaffold graft, skin grafts, flap transposition, platelet-rich plasma, and rehabilitation, which ultimately saved the patient's life and led to healing of all the wounds.

Leucocyte-Rich Platelet-Rich Plasma Enhances Fibroblast and Extracellular Matrix Activity: Implications in Wound Healing

Background: Platelet-rich plasma (PRP) is an autologous blood product that contains a high concentration of platelets and leucocytes, which are fundamental fibroblast proliferation agents. Literature has emerged that offers contradictory findings about leucocytes within PRP. Herein, we elucidated the effects of highly concentrated leucocytes and platelets on human fibroblasts. Methods: Leucocyte-rich, PRP (LR-PRP) and leucocyte-poor, platelet-poor plasma (LP-PPP) were compared to identify their effects on human fibroblasts, including cell proliferation, wound healing and extracellular matrix and adhesion molecule gene expressions. Results: The LR-PRP exhibited 1422.00 ± 317.21 × 10³ platelets/µL and 16.36 ± 2.08 × 10³ white blood cells/µL whilst the LP-PPP demonstrated lower concentrations of 55.33 ± 10.13 × 10³ platelets/µL and 0.8 ± 0.02 × 10³ white blood cells/µL. LR-PRP enhanced fibroblast cell proliferation and cell migration, and demonstrated either upregulation or down-regulation gene expression profile of the extracellular matrix and adhesion molecules. Conclusion: LR-PRP has a continuous stimulatory anabolic and ergogenic effect on human fibroblast cells.

Inorganic polyphosphate in platelet rich plasma accelerates re-epithelialization in vitro and in vivo

Wound healing requires well-coordinated events including hemostasis, inflammation, proliferation, and remodeling. Delays in any of these stages leads to chronic wounds, infections, and hypertrophic scarring. Burn wounds are particularly problematic, and may require intervention to ensure timely progression to reduce morbidity and mortality. To accelerate burn wound healing, Platelet-Rich Plasma (PRP)¹ can be of value, since platelets release growth factor proteins and inorganic polyphosphates (polyP) that may be integral to wound healing. We used polyP-depleted keratinocyte (HaCaT) and fibroblast cell culture models to determine cell proliferation and scratch-wound repair to determine if polyP, platelet lysate, or combined treatment could accelerate wound healing. While polyP and PRP significantly reduced the open scratch-wound area in fibroblasts and keratinocytes, polyP had no effect on keratinocyte or fibroblast proliferation. PRP was also evaluated as a treatment in a murine model of full thickness wound healing in vivo, including a treatment in which PRP was supplemented with purified polyP. PRP induced significantly more rapid re-epithelialization by Day 3. Pure polyP enhanced the effects of PRP on epithelial tongues, which were significantly elongated in the PRP + high-dose polyP treatment groups compared to PRP alone. Thus, PRP and polyP may serve as an effective therapeutic combination for treating wounds.

Fat grafting and platelet-rich plasma for the treatment of diabetic foot ulcers: A feasibility-randomised controlled trial

Chronic, nonhealing diabetic foot ulcers (DFU) are increasing in prevalence and are often unresponsive to conventional therapy. Adipose tissue, containing adipose-derived stem cells, and platelet rich plasma (PRP) are regenerative therapies rich in growth factors which may provide a solution to chronic wound healing. This study aimed to assess the feasibility of conducting a definitive randomised controlled trial (RCT) to investigate the efficacy of these therapies for the treatment of DFU. This was a single centre, feasibility, three-arm, parallel group RCT. Eligible DFU patients were randomised on a 1:1:1 basis to three intervention arms: control (podiatry); fat grafting; fat grafting with PRP. The intervention was delivered once and patients were followed-up for 12 weeks. The primary objective was to assess measures of trial feasibility. Clinical outcomes and health-related quality of life (HRQoL) were also evaluated. Three hundred and thirty four patients were screened and 32 patients (9.6%) were deemed eligible with 18 enrolled in the trial (6 per arm) over 17 months. All participants completed the trial with no withdrawals or crossover. Participant engagement was high with most HRQoL questionnaires returned and only 4.8% follow-up appointments missed. There were five adverse events (AEs) related to the trial with no serious AEs. Five (28%) of the wounds healed. There was no difference between any of the groups in terms of clinical outcomes. This feasibility study demonstrated that a multi-centre RCT is safe and feasible with excellent patient engagement. We have highlighted crucial information regarding methodology and recruitment, which will guide future trial design. Registration number: NCT03085550 clinicaltrials.gov. Registered 01/03/2017.

Effect of photobiomodulation associated with cell therapy in the process of cutaneous regeneration in third degree burns in rats

Due to the complexity involved in the healing process of full thickness burns, the literature looks for alternatives to optimize tissue reconstruction. The objective of this study was to explore the action of photobiomodulation therapy associated with MSCs in the healing process of third degree burns. A total of 96 male Wistar rats were used, distributed in four groups with 24 animals each: Control Group, Laser Group, Cell Therapy Group, and Laser Group and Cell Therapy. The burn was performed with aluminum plate (150 °C). We performed analysis of wound contraction, histology, immunohistochemistry, birefringence analysis, and immunoenzymatic assay to evaluate tissue quality. Our results demonstrate that the association of the techniques is able to accelerate the repair process, modulating the inflammatory process, presenting a cutaneous tissue with better quality. Thus, we conclude that the use of photobiomodulation therapy associated with cell therapy is a promising treatment in the repair of total thickness burns.

Wound healing properties and antimicrobial activity of platelet-derived biomaterials

We analyzed the potential antibacterial effects of two different PdB against methicillin-resistant S. aureus and P. aeruginosa. The third-degree burn wound healing effects of PdB was also studied. Blood samples were obtained from 10 healthy volunteers and biological assays of the PdB were performed and the antimicrobial activity against MRSA and P. aeruginosa was determined using disk diffusion (DD), broth microdilution (BMD), and time-kill assay methods. 48 Wistar albino rats were burned and infected with MRSA. Two groups were injected PdB, the control groups were treated with plasma and received no treatment respectively. In the next step, the rats were euthanized and skin biopsies were collected and histopathologic changes were examined. The results of DD and BMD showed that both PdB performed very well on MRSA, whereas P. aeruginosa was only inhibited by F-PdB and was less susceptible than MRSA to PdBs. The time-kill assay also showed that F-PdB has an antibacterial effect at 4 hours for two strains. Histopathological studies showed that the treated groups had less inflammatory cells and necrotic tissues. Our data suggest that PdB may possess a clinical utility as a novel topical antimicrobial and wound healing agent for infected burn wounds.

Bioactive Medications for the Delivery of Platelet Derivatives to Skin Wounds

Chronic wounds are the result of alterations in the complex series of events of physiological wound healing. In particular, the prolonged inflammation results in increased protease activity, in the deg-radation of extracellular matrix (ECM) and of growth factors (GFs). The relevance of platelet GFs in maintaining and restoring the complex equilibrium of different moments in wound healing is well recog-nized. Moreover, the observed decrease of their levels in chronic wounds suggested a possible therapeutic role of the external application to the wounds. It has been also pointed out that tissue regeneration can be more efficiently obtained by the synergic use of different GFs. Platelet derivatives such as platelet-rich plasma (PRP) and platelet lysate (PL) are able to release GFs in a balanced pool. Their therapeutic use in regenerative medicine and wound healing has been therefore more and more frequently proposed in clini-cal trials and in the literature. The development of a suitable formulation able to control the GFs release rate, to protect the GFs, and to assure their prolonged contact with the wound site, is of paramount im-portance for the therapeutic success. The present review considers some formulation approaches for PRP and PL application to wounds

A Retrospective Study on the Use of Dermis Micrografts in Platelet-Rich Fibrin for the Resurfacing of Massive and Chronic Full-Thickness Burns

The coverage of massive burns still represents a big challenge, even if several strategies are to date available to deal with this situation. In this study, we describe the use of a combination of platelet-rich fibrin and micrograft spray-on skin in order to increase the yield of grafted cells in patients. We treated a total of five patients, of which two were affected by massive burns and three with chronic burn wounds. Briefly, autologous micrografts were obtained by Rigenera technology using a class I medical device called Rigeneracons. The micrografts were then combined with PRF and sprayed on the wound bed by a Spraypen. Before applying PRF/micrograft spray-on skin, the wound bed was covered with an Integra® dermal template, and the wounds were dressed with a layer of antimicrobial dressing applied directly over the silicone layer. When the silicone layer of the dermal template started showing signs of separation, the wound was considered ready for grafting. In all cases, we observed a fast and complete skin graft on average after 7-10 days by PRF/micrograft spray-on skin treatment. In particular, two patients with massive burns reported rapid reepithelialization, and three patients with chronic burn wounds, two of whom had failed skin grafts before the procedure, had complete wound healing within a week. In conclusion, the results showed in this study suggest that the use of PRF/micrograft spray-on skin represents a promising approach in the management of burns or chronic burn wounds.

Topical Insulin Modulates Inflammatory and Proliferative Phases of Burn-Wound Healing in Diabetes-Induced Rats

The healing time of burn wounds depends on surface area and depth of the burn and associated comorbidities. Diabetes mellitus (DM) causes delays in the healing process by extending the inflammatory phase. Treatment with topical insulin can improve the inflammatory phase, restore metabolic dysregulation, and modulate impaired cellular signaling in burn wounds. The objective of this study was to evaluate markers of the inflammatory and proliferative phases of second-degree burns after topical insulin treatment in diabetic rats. Type I DM was induced with streptozotocin in male Wistar rats. The animals' backs were shaved and subjected to thermal burning. Rats were randomized into two groups: control diabetic (DC) and insulin diabetic (DI). At Days 7 and 14 postburn, rats were euthanized, and wound-tissue sections were evaluated by hematoxylin and eosin, Weigert, and Verhöeff staining, immunohistochemistry-paraffin, and enzyme-linked immunosorbent assay. A significant increase in reepithelialization was seen on Days 7 and 14 in DI versus DC rats. On Day 7, interleukin (IL)-1β, IL-6, monocyte chemotactic protein (MCP)-1, and F4/80 expression were increased in DI versus DC rats. On Day 14, MCP-1 expression was decreased and F4/80 increased in DI versus DC rats. On Days 7 and 14, Ki-67, transforming growth factor-β1, vascular endothelial growth factor expression, and formation of elastic fibers were increased in DI versus DC rats. Topical insulin modulates burn-wound healing in diabetic animals by balancing inflammation and promoting angiogenesis and formation of elastic fibers.

Platelet-rich plasma, a powerful tool in dermatology

Platelet-rich plasma (PRP), a platelet concentrate contained in a small volume of plasma, has become a promising option in the last decade to treat different diseases related to the skin due to its high concentration of growth factors. When it is of autologous origin, it decreases the probability of suffering adverse reactions and transfusion-transmitted infections, thus it is an optimal and safe therapy for the patient. PRP has been used in the treatment of several dermatological conditions such as acne, alopecia, and skin ulcers. Its use has also extended to other skin conditions such as melasma, hyperpigmentation, and burns, where it stimulates tissue repair and regeneration. The purpose of this article is to review the management and treatment of different dermatological alterations with PRP. Although there are a variety of studies that support the use of PRP, more research is needed to standardise the protocols for obtaining, processing, and applying it as well as understanding the biological and molecular bases of its functioning.

Platelet-rich plasma as a site-targeted approach in wound healing: a molecular perspective

Wound healing remained an equation with multiple variables that experts in the medical field are trying to solve. The need to find an adjuvant that can quicken the healing process is increasing with every day, as longer wound healing times raise the risk of infections. Platelet-rich plasma is a promising tool promoting faster healing in a variety of wounds (thermal wounds, burn wounds, surgeries, etc.), as a series of studies present encouraging results in patients that received platelet-rich plasma treatment. The aim of this paper is to review and comment on the useful benefits and limitations of using platelet-rich plasma as an adjuvant strategy in wound healing, emphasizing on skin related wounds.

Evaluate the effects of platelet rich plasma (PRP) and zinc oxide ointment on skin wound healing

In this study efficiency of platelet rich plasma (PRP) and zinc oxide on full thickness wounds created on rabbits was researched. This study conducted on 24 New Zealand rabbits divided 2 groups. A circular of 1.5 × 1.5 cm (2.5 cm²) full thickness skin wound was created under the general anesthesia. 1 ml PRP (5.503106/mm³) was applied to the one of the wounds subcutaneously. To the other wound 1 mm³ zinc oxide ointment was applied once a day during the study. Wound contraction rates were measured, biopsy materials were collected and evaluated macroscopically and histopathologically postoperatively 3rd, 7th and 15th days. As a result it is determined that PRP and zinc oxide accelerated wound contraction rates between the groups were determined as 3rd day p = 0.007, 7th day p = 0.0002 and 15th day p = 0.002.

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Wound healing is inborn to all species and is the biologic procedure by which the body repairs itself after injury, whichever it be traumatic, complicated, infected and/or surgical.

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Platelet rich plasma (PRP) gel is measured to be progressive wound treatment for acute and chronic wounds. PRP gel has mainly been applied to improve or accelerate healing of wound.

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Zinc is a vital trace element in the human body and its significance in wellbeing and infection is valued. Zinc deficiency of genetic or dietary cause can prompt neurotic, pathologic and physiological changes and deferred wound healing.

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Topical treatment with autologous PRP can be used as clinical therapy and can enhance tissue healing and enhanced angiogenesis compared to zinc oxide treatments.

The use of fat grafting and platelet-rich plasma for wound healing: A review of the current evidence

Fat grafting is becoming a common procedure in regenerative medicine because of its high content of growth factors and adipose derived stem cells (ADSCs) and the ease of harvest, safety, and low cost. The high concentration of ADSCs found in fat has the potential to differentiate into a wide range of wound-healing cells including fibroblasts and keratinocytes as well as demonstrating proangiogenic qualities. This suggests that fat could play an important role in wound healing. However retention rates of fat grafts are highly variable due in part to inconsistent vascularisation of the transplanted fat. Furthermore, conditions such as diabetes, which have a high prevalence of chronic wounds, reduce the potency and regenerative potential of ADSCs. Platelet-rich plasma (PRP) is an autologous blood product rich in growth factors, cell adhesion molecules, and cytokines. It has been hypothesised that PRP may have a positive effect on the survival and retention of fat grafts because of improved proliferation and differentiations of ADSCs, reduced inflammation, and improved vascularisation. There is also increasing interest in a possible synergistic effect that PRP may have on the healing potential of fat, although the evidence for this is very limited. In this review, we evaluate the evidence in both in vitro and animal studies on the mechanistic relationship between fat and PRP and how this translates to a benefit in wound healing. We also discuss future directions for both research and clinical practice on how to enhance the regenerative potential of the combination of PRP and fat.

Advancements in Regenerative Strategies Through the Continuum of Burn Care

Burns are caused by several mechanisms including flame, scald, chemical, electrical, and ionizing and non-ionizing radiation. Approximately half a million burn cases are registered annually, of which 40 thousand patients are hospitalized and receive definitive treatment. Burn care is very resource intensive as the treatment regimens and length of hospitalization are substantial. Burn wounds are classified based on depth as superficial (first degree), partial-thickness (second degree), or full-thickness (third degree), which determines the treatment necessary for successful healing. The goal of burn wound care is to fully restore the barrier function of the tissue as quickly as possible while minimizing infection, scarring, and contracture. The aim of this review is to highlight how tissue engineering and regenerative medicine strategies are being used to address the unique challenges of burn wound healing and define the current gaps in care for both partial- and full-thickness burn injuries. This review will present the current standard of care (SOC) and provide information on various treatment options that have been tested pre-clinically or are currently in clinical trials. Due to the complexity of burn wound healing compared to other skin injuries, burn specific treatment regimens must be developed. Recently, tissue engineering and regenerative medicine strategies have been developed to improve skin regeneration that can restore normal skin physiology and limit adverse outcomes, such as infection, delayed re-epithelialization, and scarring. Our emphasis will be centered on how current clinical and pre-clinical research of pharmacological agents, biomaterials, and cellular-based therapies can be applied throughout the continuum of burn care by targeting the stages of wound healing: hemostasis, inflammation, cell proliferation, and matrix remodeling.

The effects of platelet rich plasma on healing of full thickness burns in swine

INTRODUCTION

Platelet rich plasma (PRP) is rich in growth factors and has been shown to improve healing in a variety of wounds. We determined the effects of PRP on healing and scarring in full thickness porcine burns with and without tangential excision and grafting (TEG).

METHODS

Standardized full thickness 5cm by 5cm burns were created on each of the backs and flanks of 10 anesthetized female pigs (25kg) using a validated model. The burns were created with a heating device that emits heat at a temperature of 400°C for a period of 30s. The burns were randomized to one of six treatments: no TEG or PRP, no TEG+PRP, early (day 2) TEG and no PRP, early TEG+PRP, late (day 14) TEG and no PRP, and late TEG+PRP. Tangential excision was performed down to viable tissue and autografts were 0.2mm thick. When used, a thin layer of autologous PRP was applied below the graft. All wounds were then treated with a topical antibiotic ointment 3 times weekly for 42 days. Digital images and full thickness biopsies were taken at 9, 11, 14, 18, 21, 28, 35 and 42days after injury to determine percentage reepithelialization, scar depth, and scar contraction. Tissue sections were stained with H&E and viewed by a dermatopathologist masked to treatment assignment.

RESULTS

There was no reduction in platelet and white blood cell concentrations in PRP and blood samples for the first 14days after-full thickness burns. A total of 120 burns were created on 10 animals evenly distributed between the six treatment groups. Burns undergoing early TEG reepithelialized fastest and with the thinnest scars followed by late TEG. Burns that did not undergo TEG had the slowest reepithelialization and greatest amount of scarring. Application of PRP had no additional effects on reepithelialization, scar depth, or scar contraction in any of the treatment groups.

CONCLUSIONS

Addition of PRP had similar effects on reepithelialization and scarring of full thickness porcine burns as standard topical antibiotic ointment regardless of whether the burns underwent excision or grafting or the timing of excision and grafting.

Early intervention in scar management and cutaneous burns with autologous platelet-rich plasma

Burn management options are controversial and a multiple-handled issue. However, platelet-rich plasma is gaining interest in several medical fields. Dermatologist worldwide are already publishing some reports about its benefits and personal experiences in their practices. A 40-year-old female with a second-degree burn by VASER-type liposculpture was treated with platelet-rich plasma and followed up for 10 months. After treatment, she showed rapid improvement with an adequate cicatrization results. Some studies suggest that the use of platelet-rich plasma which contains cytokines and growth factors that participate in cellular repair and cellular differentiation, thus improving healing time and re-epithelization. We present the case of a patient with a second-degree burn that rapidly improved with autologous platelet-rich plasma.

Opening new horizons in regenerative dermatology using platelet-based autologous therapies

Biological therapeutic therapies are gaining the attention of scientists and medical doctors. Accumulating evidence suggests that blood-derived autologous therapies are safe and effective treatments for skin repair and wound healing. The fibrin network formed after plasmatic activation and the autologous growth factors released when platelets degranulate constitute a real biological medicine that has been shown to promote cell recruitment, stimulate new blood vessel formation, reduce inflammation as well as protect from local infections. This perspective highlights recent basic and clinical results published on blood-derived autologous therapies in the field of regenerative dermatology and discusses potential challenges and future prospects.