Programme – Saturday, June 2nd
'Please note that the programme will be updated continuously'.
09:00 - 10:30
Plenary session: Appearance matters...Ballroom IV-V
09:00 - 09:30
Nicola Stock, PhD
The Psychology of Appearance: Why Appearance Matters
Nicola Stock, PhDResearch Psychologist, Institute/Department Centre for Appearance Research, University of the West of England
Appearance plays an important role in our day to day lives, both in how we see ourselves and in how we interact with other people. This presentation will outline the psychological and social challenges of having an appearance which is considered ‘different’ from the norm, and the importance of integrating the patient perspective into all stages of research and treatment.
» Take home message:
How the patient feels about his or her appearance is a vital consideration for research and practice in the field of scarring.
09:30 - 10:00
Albert Wolkerstorfer, MD, PhD
Albert Wolkerstorfer, MD, PhDDermatologist, AMC, the Netherlands
Pigmented lesions are extremely common and can vary from temporary, hardly visible to permanent and highly noticeable patches. Especially persons with darker skin types tend to develop patches with a high contrast.
Patients may experience psychosocial distress and social stigmatization. It is important to stress that the impact of these “harmless” discolorations can be huge, which has been confirmed for both light (hypopigmented) and dark (hyperpigmented) patches in quality of life studies.
10:00 - 10:30
Nancy van Loey, PhD
Burn severity in relation to self-esteem: differences between men and women
Nancy van Loey, PhDSenior Researcher, Association of Dutch Burn Centers, dept Behavioural Research & Utrecht University, dept Clinical Psychology
Self-esteem is a broad multifactorial concept that can be affected after burn injury. There is some evidence that women have worse psychological outcomes compared to men. Therefore, further research that investigates the relationship between burn severity and self-esteem, specifically focusing on possible differences between men and women, is warranted. Indeed, a prospective study showed that burn severity was directly related to lower self-esteem in women, when controlled for depressive symptoms. In men, there was an indirect relationship. This indicates that women may benefit from other psychological treatments.
10:30 - 11:00
Break: visit exhibition & poster presentationsBallroom I-II
11:00 - 12:30
Two paralell sessions & sponsored workshop in this timeslot
Session 11 – Wound healingBallroom IV-V
- 11:00 - 11:20 Prof. Julia Kzhyshkowska, PhD
- 11:20 - 11:40 Prof. Shashwati Roy, PhD
11:40 - 11:50
Prof. Elof Eriksson, MD, PhD
Topical high concentrations of antibiotics formulated in an alginate hydrogel prevents injury progression and stops infection in a porcine burn model
Prof. Elof Eriksson, MD, PhDHarvard Medical School, Surgery, USA
Serious burns often develop invasive infection that can progress to septic shock and death. A critical factor in burn pathophysiology is the time from injury to delivery of antimicrobial therapy and surgical treatment of the burns. Military strategists are concerned that in future wars there will be a need for Prolonged Field Care because of delayed transport from remote areas of warfare. This delay may be as long as 4-7 days. The purpose of this project was to validate the use of a hydrogel formulated with high concentrations of antibiotics for the immediate topical single dose delivery to burn wounds and determine if this treatment prevents or reduces experimentally induced infections if standard treatment is delayed for up to 7 days.
Porcine partial-thickness burn wounds were created and infected with either A. baumannii, C. albicans, P. aeruginosa or S. aureus. Subsequently, the burns were treated topically for 7 days with a high concentration of antibiotics (1000xMIC: Minocycline, Gentamicin, Vancomycin, 10xMIC Diflucan) formulated in an alginate hydrogel. The hydrogel treatment was compared to non-treated, silver sulfadiazine cream treated burns and to IV antibiotic treatment. On day 7 the burns were harvested for quantitative bacteriology and histology.
The antibiotic hydrogels with all the used antibiotics (n=6 wounds/group) decreased the number of bacteria in the tissue in comparison to controls. E.g. 1000xMIC minocycline gel treated A. baumannii inoculated burns contained 1.3 log10 CFU/g and IV minocycline treated burns 6.2 log10 CFU/g bacteria (p<0.001). The treatments reduced depth of tissue necrosis and wound area in comparison to controls. E.g. depth of necrosis in 1000xMIC minocycline treated burns was 0.3 mm whereas the depth in the IV treated burns was 0.7 mm (p<0.01).
The topically applied antibiotic/hydrogel formulations stopped burn depth progression, minimized tissue loss and greatly decreased tissue bacterial counts.
11:50 - 12:00
Prof. David Benjamin Lumenta, MD, PhD
Cellulose (Epicite) as application carrier for wounds and burns - preliminary results
Prof. David Benjamin Lumenta, MD, PhDMedical University of Graz, Division of Plastic, Aesthetic and Reconstructive Surgery, Department of Surgery, Austria
First experiences of clinical application of a cellulose-based material in burns and wounds, as well as preliminary results of its performance in an ongoing controlled prospective clinical trial.
Empiric evaluation of a best-practice model for dressing changes in chronic wounds and superficial dermal burns.
Monocentric clinical trial on skin-graft donor sites with evaluation of Hollander Wound scale, Pain (Visual Analogue Scale), duration and frequency of dressing changes, time-to-healing, and colorimetry.
Dressing change recommended after 2-4 days in acute phase depending on soaking in antiseptic solution and wound depth. In clean wounds no further change until complete healing necessary. Current evaluation of prospective trial revealed excellent toleration of dressing material with cooling effect on wounds, no adverse reactions to dressing material (ongoing patient recruitment).
The high water content, form adaptability and the material's soaking capability make it an excellent candidate for future evaluation as carrier for antiseptics and advanced therapies in wounds and burns.
12:00 - 12:10
Zjir Rashaan, MD
Flaminal® versus Flamazine® in the treatment of partial thickness burns: a randomized controlled trial on clinical effectiveness
Zjir Rashaan, MDRode Kruis Ziekenhuis, Surgery, Burn Unit, the Netherlands
Partial thickness burns are the most frequently reported burn injuries. However, there is no consensus on the optimal treatment of partial thickness wounds.
To evaluate the clinical-effectiveness of Flaminal® Forte versus Flamazine® in the treatment of partial thickness burns.
In this two-arm open multi-center randomized controlled trial, 89 patients were randomized between Flaminal® Forte and Flamazine® and followed for 12 months. Competent or temorary incompetent (because of sedation and/ or intubation) patients, 18 years of age or older with acute partial thickness burns and a total body surface area (TBSA) of less than 30% were eligible for this study. Outcomes were time to wound healing, number of patients required operation, pain and pruritus (Visual Analogue Thermometer, VAT), pain-related and anticipatory anxiety (The Burn Specific Pain Anxiety Scale, BSPAS).
89 patients were randomized (Flaminal® Forte n=41, Flamazine® n=48). Patients treated with Flaminal® Forte required 19% (p=0.001) less dressing changes compared with the Flamazine® group. There were no statistically significant difference between groups regarding time to wound healing (Flaminal® 18 days (range 8-49 days), Flaminal® 16 days (range 7-48 days, p=0.24), number of patients requiring operation, pain, pruritus or pain-related and anticipatory anxiety. 29/37 (78%) patients in the Flaminal® group developed wound colonisation compared with 13/41 (32%, p<0.001) patients in the Flamazine® group. However, no statistically significant difference between groups were found with respect to wound infection and/ or use of antibiotics.
Patients treated with Flaminal® Forte required less dressing changes compared with patients treated with Flamazine® in the treatment of partial thickness burns, while no other significant differences were found between both treatment groups based on clinical outcomes. Therefore, results on cost-effectiveness and quality of life must determine which treatment to justify in the treatment of partial thickness burns.
12:10 - 12:20
Ibrahim Korkmaz, MSc
Increased nox2 expression in keratinocytes after burn injury
Ibrahim Korkmaz, MScVU University Medical Center, Department of Pathology, The Netherlands
NADPH oxidase (NOX) proteins have a variety of sometimes opposing cellular functions ranging from apoptosis to cell growth. In diabetes, NOX2 was shown to impair wound healing of the skin in vitro. However, a putative role of NOX2 in burn wounds is not known. It was shown in ischemia/reperfusion models that complement inhibitor C1-esterase inhibitor (C1inh) inhibits NOX, and we previously showed that C1inh induced reepithelialisation in burn wounds, we investigated whether NOX2 could also play a role in burn wounds.
We used an in vivo rat dorsal burn wound model consisting of non-burned healthy control (n=6), burn-injured (n=7) and burn-injured C1inh-treated (n=7) Wistar rats. After 14 days, the rats were terminated. From the burn-injured rats, the entire wound as well as healthy skin from the hind leg (internal control) was excised. From the control rats dorsal skin was excised. In these skin samples NOX2 was analysed immunohistochemically.
No dyskeratotic cells, indicative for apoptosis of keratinocytes, were found. NOX2 expression was found in non-burned control skin in keratinocytes located in the stratum basale of the epidermis, while in burn-injured rats NOX2 expression was significantly increased in the suprabasal layer of the epidermis in burn wounds, but not in internal control skin. In burn wounds C1inh induced a decrease in NOX2 positive keratinocytes.
This study suggests that NOX2 could play a negative role in burn wound reepithelialisation and that C1inh can prevent this. However, further research is necessary to investigate the underlying mechanism in more detail.
Session 12 – Advanced therapiesGriffioen
11:00 - 11:20
Fabienne Hartmann-Fritsch, PhD
Application of an ATMP in Scar Management
Fabienne Hartmann-Fritsch, PhDProject Co-Leader and Clinical Trial Manager, University of Zurich, Switzerland / Wyss Zurich
The treatment of full-thickness skin defects represents a significant and common clinical problem worldwide. A bio-engineered autologous skin substitute would significantly reduce the problems observed with today’s gold standard. A research group at the University Children’s Hospital Zurich, Switzerland, has developed an autologous tissue-engineered skin graft to treat skin defects: “denovoSkin”. Classified as Advanced Therapy Medicinal Product (ATMP), denovoSkin serves as example for this talk to discuss opportunities and challenges for the application of ATMPs to treat skin defects.
» Take home message:
Advanced Therapy Medicinal Products (ATMPs), although often challenging in respect to manufacturing, logistics, costs, and regulatory, have a great potential and may have a major impact on the welfare of affected patients.
11:20 - 11:30
Ekaterina Kalabusheva, PhD
Hair Follicle Dermal Papilla Cells As a Potential Novel Source for Diabetic Wound Healing
Ekaterina Kalabusheva, PhDKoltzov Institute of Developmental Biology of Russian Academy of Sciences, Cell Biology Laboratory, Russia
Further development of cell-based therapy in diabetic ulcers treatment involves the exploration of novel easy-accessible mesenchymal stem cell (MSC) sources protected from harmful influence of hyperglycemia. Hair follicle dermal papilla (DP) cells possess MSC properties and could become an alternative to ameliorate impaired diabetic wound healing. In this research we compared the diabetes influence on mouse MSC from DP and adipose tissue and investigated the DP cells behaviour in inflammation microenvironment.
The proliferation rate of DP and adipose MSC and dermal fibroblasts from streptozotocin-induced diabetic mice was analyzed using MTT assay. Human and mouse DP cells and dermal fibroblasts were cultured in presence of20ng/ml TGFβ and 1%O2 atmosphere to analyse the differentiation to myofibroblasts direction.
DP cells and adipose MSC from healthy animals demonstrated the same proliferation level, adipose diabetic DP cells maintains this level, while the proliferation of diabetic adipose MSC significantly decreased. Inflammation microenvironment, TGFβ and hypoxic atmosphere, stimulated myofibroblast differentiation of mouse DP cells, although didn’t affect on human adult DP cells.
DP cells are protected in vivo from diabetes influence that makes this source the most promising treatment for stem cell therapy. DP cells keep MSC abilities to enhance wound healing and fibroblasts characteristics to promote granulation formation that is necessary for success diabetic wound closure.
The work was funded by the Russian Science Foundation (Project No16-14-00204).
11:30 - 11:40
Gabrielle Dijksteel, MSc
Antimicrobial peptide treatment to prevent aberrant scarring in MRSA infected wounds
Gabrielle Dijksteel, MScVSBN, R&D, the Netherlands
MRSA infections are associated with delayed wound healing and aberrant scarring in burn patients. Therefore, it is important to eradicate these bacteria. However, the treatment of such infections has become a challenging task due to antibiotic-resistance. Additionally, current topical creams hamper the wound healing. Therefore, we have studied the potential of a new synthetic antimicrobial peptide P148 in terms of safety and efficacy against MRSA.
10^5 CFU/mL MRSA were exposed to increasing concentrations of P148 (0 to 0.3mM) in PBS, human plasma or burn eschar extract to mimic the wound environment. After incubation for 30 min, the surviving bacterial numbers were determined.
The efficacy of P148 was determined in ex vivo models: excisional or burn wound models, tape-stripped- and intact skin. These models were contaminated with 10^5 CFU/mL MRSA for 1 hour. After treatment with 20µL 3mM P148 for 1 hour, the surviving bacterial numbers were determined.
For safety, the effect of P148 on the re-epithelialization was assessed in burn wound models by measuring the outgrowth and the number of proliferating keratinocytes. We compared P148 to two standard treatments; silver sulfadiazine and bactroban.
The required concentration of P148, to eradicate 50% of MRSA (IC50) in PBS was 6,3 10^-4 mM, while in plasma and eschar extract the IC50 was 2 10^-2 mM and 3,2 10^-2 mM, respectively.
P148 significantly reduced the bacterial load in all four ex vivo wound models. P148 was slightly more effective on tape-stripped skin and less effective in the excision wound model.
Contrary to silver sulfadiazine and bactroban, P148 did not affect the re-epithelialization.
P148 was more effective in PBS than in plasma or eschar extract. P148 effectively eradicated MRSA in different wound types and did not interfere with re-epithelialization. Taken together, P148 has high potential as an alternative treatment against MRSA.
11:40 - 11:50
Bouke Boekema, PhD
Cold atmospheric pressure plasma: a novel treatment modality in diabetic foot ulcers
Bouke Boekema, PhDBeverwijk, the Netherlands
Diabetic foot ulcers are common complications of diabetes mellitus and greatly increase the risk of infection and amputation. A novel method to decrease the likelihood of infection and to help cure ulcers is cold atmospheric plasma (CAP). The newly developed flexible volume Dielectric Barrier Discharge (vDBD) produces plasma in ambient air. We studied the efficacy and safety of this simple to use plasma device.
The bactericidal effect was tested on Staphylococcus aureus on agar, in collagen matrices and on ex vivo human skin. Safety was monitored preclinically by measuring cellular activity in skin biopsies, after multiple daily treatments. Possible DNA damage was monitored by staining for H2AX, which is a marker for double strand DNA breaks. Safety was also monitored clinically in human subjects with diabetic foot ulcers. Subjects were treated daily with CAP for 10 days in 2 weeks. Primary endpoint was occurrence of serious adverse events (SAE) as a result of treatment. Standard protocols for wound treatment were deployed.
High reduction of S. aureus in vitro was reached in 1-2 minutes of plasma treatment. Plasma treatment was less efficient on ex vivo dermal samples. Plasma did not affect viability or DNA integrity of skin biopsies when used for 1-2 min. Repeated daily treatments of up to 4 times slightly lowered viability of skin biopsies.
Interim clinical data were available for 17 patients. Five SAE were reported but these were unrelated to the plasma treatment. 60% of subjects experienced transient mild tingling during one or more applications. No wound expanded during treatment and two wounds healed.
The novel CAP device kills bacteria on skin, without affecting viability of dermal cells in laboratory tests. During the clinical study no SAE related to the treatment occurred, while AEs were mild and transient.
11:50 - 12:00
Thomas Rose, MD
Decellularized Human Dermal Matrices for the Treatment of Burn Patients
Thomas Rose, MDQueen Astrid Military Hospital, Burn Wound Centre, Belgium
Recently we have developed a novel Decellularized Human Dermal Matrix (DHDM), having both 3D structure and composition well preserved. In order to decrease the need for autografting in patients with extensive deep burns, we plan to use this DHDM, together with autologous cells. The main objective of this preliminary work is the evaluation of the integration of the DHDM in burn wounds and its ability to receive skin autografts.
Cryopreserved allogeneic skin (about 0.4 mm thick) was obtained from post mortem human donors and was used to prepare DHDMs. A two-step decellularization method, involving a hypertonic treatment followed by a detergent treatment, was used to prepare the DHDMs. After removal of the detergent, the DHDMs were cryopreserved. Bacteriological/mycological testing, histological evaluation, MTT viability testing and High-Definition Optical Coherence Tomography imaging methods were used for quality control. The DHDMs were applied to burn wounds and were maintained in place by stitches. Wounds were dressed with Surfasoft® and covered with Mepitel and Acticoat dressings. Visual evaluation, with photographic records, of the DHDM integration was performed.
It was observed that burn wounds treated with DHDM were not infected. After 2 to 3 weeks the DHDMs were integrated into the burn wounds and wounds were ready to receive skin autografts.
Conclusively, the DHDMs integration in burn wound can be achieved. In the next step the use of autologous cells together with DHDM should improve revascularisation, shorten the integration time and reduce the need for autografting in patients with extensive deep burns.
12:00 - 12:10
Electronic micro-needling on mature burn scars: a case series report
Ester PetersSkin Therapy, Rotterdam, the Netherlands
Only few therapies can improve mature burn scars with non-surgical techniques. Micro-needling is a minimally-invasive technique that needs little after-care and is widely used for skin resurfacing. Literature on its effect on mature burn scars is scarce. The main objective of this report is to investigate and discuss the effects of an electronic micro-needling-device on several characteristics of mature burn scars.
Skin elasticity was examined with Cutometer®, colour was assessed with a Skin Colorimeter® and scar thickness and -density with a 22MHz High-Frequency Ultrasound device. A clinical assessment of the scar by both the patient (POSAS-P) and the observer (POSAS-O) was obtained by the POSAS.
In total 5 burn patients were treated twice with the electronic micro-needling-device. The patients were tested before the treatment, after two months just before the second treatment and after five months. For statistical analysis, the Friedman Test was used to determine statistically significant differences over time.
The mean age of the patients was 47 years (±9.5y) and scars were on average 49 months old (±27,9m).The results showed a significant improvement (p<.05) over time for itch, pliability, thickness and texture assessed by the patient and for thickness, pliability, texture and global score assessed by the observer. For the objective measurements, a statistically significant improvement over time was obtained for elasticity, measured with the Cutometer® (p=.022) and thickness, assessed with high-frequency ultrasound (p=.041). No improvement could be recorded for objective colour measurements.
Electronic micro-needling can give added value to the non-surgical treatment of hypertrophic, irregularly shaped, mature burn scars. In the future, a comparison with a control group and a bigger sample size are necessary. An objective measurement of the scar texture and a distinction between specific indications are also desirable.
12:10 - 12:20
Carlotta Scarpa, MD
The role of the Biophotonic technology in the treatment recalcitrant wounds
Carlotta Scarpa, MDPlastic Surgery Clinic, Padua’s University, Italy
» Background and aims:
Usually applied for odontoiatric purposes, the Biophotonic technology is actually one of the most interesting innovation in wound healing. In this study we present our experience with the light reactive topical gel (LumihealTM) in the treatment of chronic wounds. Methods: We selected patients affected by chronic wounds (for example pressure ulcers, vascular ulcers, steroid ulcers) and we performed the treatment 2 times/week, for 5 minutes every session, for almost 8 weeks.
In our experience we noted an increased wound healing due to: 1) the gradual reduction of the ulcer’s dimension; 2) a reduced perilesional inflammation; 3) an increased debridement, 4) the superficialization of the wound.
The Biophotonic treatment is an easy and quick treatment which can be considered as a good support in the recalcitrant chronic wounds.
Sponsored Workshop 6 – Laser, Scar Assessment and ResearchEsperance Sign-up required
12:30 - 13:30
Lunch break: visit exhibition & poster presentationsBallroom I-II
13:30 - 15:00
Two paralell sessions in this timeslot
Session 13 – Regenerative medicineBallroom IV-V
13:30 - 13:50
Willeke DaamenAssistant professor, Radboud university medical center, RIMLS, Dept. of Biochemistry
This presentation will address the preparation of (functionalized) collagen-based biomaterials and its application in soft tissue regeneration. In particular, the incorporation of glycosaminoglycans and growth factors in such materials is considered, exemplified by a study where biomaterials were evaluated upon in utero closure of full-thickness skin defects in sheep. Wound healing was assessed postnatally, using semi-quantitative histological analysis on excised skin specimens and comprehensive gene expression microarray analysis on laser-dissected dermis and epidermis.
» Take home message:
The usage of collagen scaffolds loaded with glycosaminoglycans and growth factors has long-term advantageous effects on soft tissue regeneration.
13:50 - 14:00
Robert Knight, MSc
Immortalised oral mucosa lamina propria-progenitor cell line derived extracellular vesicles drive
Robert Knight, MScCardiff University, School of Dentistry, Wales
Scar tissue formation during wound repair can be devastating, often leading to reduced tissue function or organ failure. However, wound healing within the buccal mucosa, occurs in a scarless manner, linked to the intrinsic properties of resident mesenchymal populations. We have reported on a novel, patent protected progenitor cell population from the buccal mucosa. These Oral Mucosa Lamina Propria-Progenitor Cells (OMLP-PCs) are multipotent, highly immuno-suppressive and anti-bacterial. Extracellular vesicles (EV) are secreted membrane bound vesicles. The smallest of EVs, exosomes, are of endosomal origin and typically range in size between 30-130nm. They have been demonstrated to play a role in cell:cell communication and also play an important role in stem cell mediated repair/regeneration.
Three OMLP-PC cell strains were hTERT immortalised to produce three immortalised OMLP-PC lines (iOMLP-PL). EVs were isolated from iOMLP-PL conditioned medium using an exosome isolation kit (ExoSpin). Exosomes were characterised based upon the Journal of Extracellular Vesicles minimal essential criteria. The effects of iOMLP-PL derived EVs were assessed in a number of in vitro wound healing assays (proliferation, migration/wound repopulation, myofibroblast formation).
iOMLP-PLs demonstrated a normal fibroblast-like morphology, expressed the expected progenitor cell surface markers but different lines demonstrated some differences with respect to their multipotency and immunosuppressive properties. One iOMLP-PL closely mirrored its related cell strain and hence this was utilised to produce EVs. EVs isolated from this iOMLP-PL were between 60-130nm in diameter and presented a round morphology with a defined lipid bilayer (Cryo EM). EVs had a floatation density as expected for exosomes. iOMLP-PL EVs significantly increased skin fibroblast proliferation and wound repopulation/migration in vitro. They also significantly inhibited myofibroblast formation in vitro when fibroblasts were cultured with TGFb1.
iOMLP-PL derived EVs significantly improve some of the key elements involved in the healing of soft tissue wounds.
14:00 - 14:10
Prof. Sue Gibbs, PhD
Introduction of hair papillae into tissue-engineered skin
Prof. Sue Gibbs, PhDVU university medical center, Dermatology, the Netherlands
Due to advancements in patient care, survival chances have increased significantly for severely burnt patients. Now the major issue has become the quality of scar formation and full restoration of skin function. Tissue-engineered skin constructs are being developed and used to treat large skin wounds where autologous skin is limiting. Although current skin substitutes mimic the human skin to a certain extent, they do not contain hair follicles. Our hair plays a major role in regulating body temperature, sensory feel, protecting body surfaces and preventing foreign matter from entering the body as well as playing a role in sexual and social communication. The aim of this study was to develop a method to amplify and reconstruct dermal papillae in vitro and to assess three methods of papillae transfer onto a wound bed in vitro.
Dermal papilla cells were isolated from human hair follicles, expanded and used to reconstruct papillae. Papilla were introduced into i) a bilayered skin substitute containing keratinocytes and melanocytes on a fibroblast populated hydrogel; ii) a collagen / elastin carrier which can be applied beneath a skin substitute or meshed autograft; and iii) a collagen / elastin carrier together with keratinocytes for direct application onto the wound bed.
Dermal papilla cells can be amplified in culture and used to reconstruct multiple papillae. Viable compact papillae were observed within the collagen hydrogel or collagen / elastin matrix of all three skin constructs. The epidermis of the skin substitute was differentiated with a stratum corneum. Transplantation of the constructs onto surrogate wound beds (dermal matrix) in an in vitro setting showed that the dermal papillae were viable for at least 11 days after transfer.
Dermal papillae can be introduced and maintained in skin constructs suitable for transplanting onto large skin wounds.
14:10 - 14:20
Peter Dungel, PhD
The potential of photobiomodulation to enhance wound healing and prevent scar formation
Peter Dungel, PhDLudwig Boltzmann Institute for Traumatology, Traumatology, Austria
» Introduction: Photobiomodulation is effective to modulate wound healing processes. Most studies of low level light therapy have been performed with lasers in red or infrared range. Previously, we could show that blue light has significant impact on the release of nitric oxide from nitrosyl complexes and can enhance tissue perfusion. In addition, light emitting diodes (LEDs) could be more feasible light sources. Here, we compared the effects of red and blue light from LED devices in vitro in a scratch wound model in three different cell lines.
A scratch wound was created in adherent cell layers of NIH3T3 fibroblasts, C2C12 myoblasts or BICR10 keratinocytes cells. Scratch wounds were treated daily for 10 min with LEDs at 470nm or 630nm, both at 50mW/cm2. Control cells were incubated without specific treatment. Effects of light on healing processes were evaluated by analysing time to closure, proliferation, apoptosis and necrosis rates.
Red light stimulated wound healing by promoting proliferation and shortening the time to closure in all three cell types. No effect on apoptosis was observed. However, blue light strongly decreased proliferation and augmented apoptosis in all cell types and increased necrosis rates in myoblasts and fibroblasts.
Our data suggest that photobiomodulation has distinct effects on cells depending on wavelengths and cell types react differently to illumination. The inhibitory effects of blue light might be used to treat hyperproliferative skin conditions and prevent scar formation. Further studies must determine the optimal light setting for each cell type involved in wound healing. Photobiomodulation would provide an easily applicable and cost-effective treatment for surface wounds.
14:20 - 14:30
Vincenzo Vindigni, MD
An histological preliminary comparison between the porous matrix from bovine and the porcin dermal matrix
Vincenzo Vindigni, MDPlastic Surgery Clinic, Padua’s University, Italy
Featured by a great mechanical stability and the ability to prevent the formation of pathological scar, the dermal subtitutes are one of the most commonly used treatment both for acute both for chronic wounds. In order to verify the performance of dermal substitutes on ulcers, we present our histological preliminary comparison between the porous matrix from bovine and the porcin dermal matrix.
» Materials and Method:
Patients affected by chronic wounds have been undergone to debridement and reconstruction with a dual step procedure applying the dermal substitutes during the debridement session, and, after 15 days, the replacement of the silicone film with autologous skin graft. In order to verify the integration between the dermal substitute and the host, we performed biopsies before the coverage with the skin graft.
All patients have had good clinical results accelerating wound healing, but the histological analyses demonstrate that there’s a different reabsorption between the porus matrix from bovine and the porcin dermal matrix. The scaffold was still visible and present in the patients treated with porous matrix.Conclusions: Dermal subtitues are nowadays one the most useful treatment to accelerate wound healing. Our analyses demonstrate a difference in persistency of scaffold between porcin and bovine dermal substitutes. Other studies are required in order to understand if the permanency of the scaffold can be useful for a better and stable wound healing.
Session 14 – Hypertrophic scars and keloidsGriffioen
- 13:30 - 13:50 Prof. Wei Liu, MD, PhD Evolution of keloid therapy: from conservative to aggressive surgical approach
13:50 - 14:00
Yara Bachour, MSc
Higher concentrations TLR6 and 10 in fibrotic contracted capsules compared to uncontracted capsules
Yara Bachour, MScVUmc, Plastic, Reconstructive and Hand Surgery, VU University Medical Center, Amsterdam, The Netherlands
The aetiology of capsular contracture after surgical implantation of breast implants remains unclear, but an important role is seen for the immune system. Toll-like receptors are immune receptors recognizing both pathogen associated molecular patterns (PAMPs) as well as damage associated molecular patterns (DAMPs). The former are present on bacteria such as Staphylococcus epidermidis (bacteria earlier associated with capsular contracture), the latter are released after (mechanical) stress. The aim of this study was to investigate the expression of TLRs 1-10 in relation to capsular contracture.
Fifty breast capsules were collected during implant removal or replacement. A sample specimen (0.5 cm3) was obtained from all tissues. The samples were divided in an uncontracted capsule group (Baker 1 or 2) and contracted capsule group (Baker 3 or 4). cDNA was synthesized from isolated mRNA from the collected specimens. PCR analyses were conducted to test for cDNA presence and to quantify concentration.
TLR6 and TLR10 were more often present in contracted samples compared to uncontracted samples (81.8% vs. 46.4%, p = 0.010; and 72.7% vs. 42.9%, p = 0.035, respectively). Mean concentrations of TLR6 and TLR10 were significantly higher in contracted samples compared to uncontracted capsules: 7.8 (SD 12.3) copies/µL cDNA vs. 4.0 (SD 3.4) copies/µL cDNA, p = 0.011 and 3.8 (SD 7.2) copies/µL cDNA vs. 1.4 (SD 1.5) copies/µL cDNA, p = 0.037, respectively.
This study shows that TLR6 and TLR10 are more often expressed in contracted capsules compared to non-contracted capsules and in higher concentrations.
14:00 - 14:10
Erik de Bakker, MD, MSc
Low Skin Irritation Threshold in patch test correlates to predisposition to Hypertrophic Scar Formation
Erik de Bakker, MD, MScVU University Medical Centre, Department of Plastic, Reconstructive and Hand surgery, Department of Dermatology, the Netherlands
Hypertrophic scar (HS) development following surgery is extremely hard to predict. It is known that some cytokines released early in HS formation are also released during skin irritation. Also it is known that the SLS irritation threshold scored from a patch test differs between individuals. The irritation threshold(IT) may therefore be a distinguishing factor between patients developing normal scar(NS) and HS. This study aims to examine an association between IT and HS formation and to determine the possible role of SLS patch testing as a tool to predict HS formation.
31 patients (NS = 15; HS = 16) were included who had previously undergone reduction mammoplasties. Four days after applying the SLS patch test, the score was read by an experienced dermatologist and with a DermaSpectrometer®. Trans-epidermal waterloss (TEWL) was determined, the stratum corneum on each test site was removed by tapestripping. Cytokines were determined with ELISA.
Visual scoring of the SLS patch test showed significant higher irritation grades in the HS patient group compared to the NS patient group both with 1% and 2% SLS (p=0.017, p=0.013). It could be predicted with 66.7% and 63.3% accuracy whether a patient developed NT or HS scar since HS has a lower IT. IL-1a release was higher in the NS group for 2% SLS. There was a trend towards an increased IL1a-IL1Ra ratio in the HS group. Dermatospectrometry and TEWL measurements showed no significant differences between the studied groups.
SLS patch testing, carried out under the supervision of an experienced dermatologist, can be used as a prognostic tool to predict the formation of HS and will allow both surgeons and patients to make a better informed decision about (aesthetic) surgery procedures. It will also allow for earlier preventative treatment of HS.
14:10 - 14:20
Frank Niessen, MD, PhD
Different properties of skin of different body sites: The root of keloid formation?
Frank Niessen, MD, PhDVUmc, Plastic Surgery, Netherlands
Keloids remain a complex problem, posing esthetical as well as functional difficulties for those affected. These scars tend to develop at anatomic sites of preference, where mechanical properties of skin vary. The differences in extra cellular matrix composition, but also vascularization and resident immune cell populations might play a role in the mechanism of keloid formation.
To examine this hypothesis, skin samples of several anatomic locations were taken from 24 human donors within zero to 36 hours after they had deceased. Collagen content and cross-links were determined through high-performance liquid chromatography. The expression of several genes, involved in extra cellular matrix production and degradation, was measured by means of real-time PCR. (Immuno) histochemistry was performed to detect fibroblasts, collagen, elastin, blood vessels, Langerhans cells and macrophages. Properties of skin of keloid predilections sites were compared to properties of skin from other locations (non-predilection sites).
The results indicated that there are site specific variations in extracellular matrix properties (collagen and cross-links) as well as macrophage numbers. Moreover, predilection sites for keloid formation contain larger amounts of collagen compared to non-predilection sites, but decreased numbers of macrophages, in particular classically activated CD40 positive macrophages.
The altered (histological, protein and genetic) properties of skin of keloid predilection sites may cause a predisposition for and contribute to keloid formation.
14:20 - 14:30
Julia Elrod, MD
Towards an ulta-sensitive aspiration device for objective scar assessment
Julia Elrod, MDUniversity Children`s Hospital Zürich, Pediatric Burn Center, Plastic and Reconstructive Surgery, Switzerland
Next to a standard clinical assessment of burn scars, an objective evaluation of scar quality and scar maturation is becoming increasingly important to inform strategies concerning skin transplantation, including dermal substitution, and to quantify the efficacy of ancillary scar treatment. In vivo suction-based skin characterization is commonly applied to determine mechanical properties of healthy tissue and scars. This method has been used within clinical studies but never became part of standardized assessment of skin tissue in clinical practice. This is mainly attributed to its time-consuming, demanding handling as well as to the high variability of the measurements. The latter is mainly due to the uncontrolled pushing force exerted by the observer. The novel suction device, utilized in the present study, was conceived to overcome this limitation.
The new device consists of a very small, ultra-light suction probe (3.5 grams) that measures the negative pressure needed to reach a predefined tissue elevation. This reveals information on the tissue stiffness by minimizing the initial deformation. We compare this novel suction device with the well-known Cutometer-MPA-580®.
Our data demonstrate the enhanced reproducibility of measurements obtained with the new technique by several observers and at different locations on the body. Differences in measurement outcomes are rationalized through corresponding finite element calculations and measurements on soft elastomers.
Results show the potential for an objective measure of biomechanical properties of skin and for scientific evaluation of the efficacy of different transplantation strategies and ancillary scar treatment. In addition, the device enables user-friendly application. Current clinical studies explore applications for assessment of scar maturation; corresponding results are presented in this talk.
Ultimately, this device could help guide treatment of burn patients and succeed in reducing development of hypertrophic scars with all their devastating consequences, e.g. the necessity for repeated corrective surgeries in children.
14:30 - 14:40
Prof. Jai Prakash, PhD
Novel peptide-based therapeutics to inhibit hypertrophic scarring
Prof. Jai Prakash, PhDMedTech Centre, University of Twente, Biomaterials Science and Technology, ScarTec Therapeutics BV, Therapeutics, the Netherlands
Hypertrophic scarring is an immense clinical problem. Currently there is no clinically approved therapy to prevent and heal scarring. Myofibroblasts are key cells responsible during scarring inducing extracellular matrix (ECM) production and contraction. Integrin alpha5 (ITGA5), a receptor for fibronectin, play a crucial role in regulation of myofibroblasts phenotype. In this study, we found an induced ITGA5 expression in myofibroblasts from hypertrophic scars. Subsequently, we developed a novel peptide (AV3) against ITGA5 and evaluated its therapeutic activity in vitro and ex vivo.
The effect of the peptide (AV3) on the human primary normal and hypertrophic fibroblasts was examined with/without activation with TGF-b1, respectively, on the expression of a-SMA, collagen-1 and contractility. Ex vivo, freshly isolated human skin from abdomen reduction patients was cultured in air-liquid interface for 7 days. The gel was applied topically and TGF-b was added into the medium on day 0 and day 3. On day 7, the skin was isolated and analyzed for collagen expression using Masson trichrome staining.
In vitro, AV3 peptide inhibited the TGF-b-mediated activation of primary human fibroblasts, as shown with reduced a-SMA expression and collagen production. In addition, AV3 significantly inhibited the contraction of fibroblasts induced by TGF-b1. Furthermore, we investigated whether AV3 is able to inhibit the hypertrophic myofibroblasts from hypertrophic scar tissue. Interestingly, AV3 inhibited the collagen expression, which indicates that AV3 might be used for inhibit the established scars. Ex vivo, TGF-b significantly induced the collagen expression in human skin and the topical application of the AV3 hydrogel reduced the intensity of the collagen staining.
ITGA5 is a crucial pathway activated in hypertrophic scars. Our in vitro and ex vivo data demonstrate that blocking of ITGA5 using novel AV3 peptide is an interesting therapeutic to be developed for the prevention and treatment of hypertrophic scars.
14:40 - 14:50
Rajiv Raktoe, MSc
Skipping to improve scar management: modulation of TGF-β signalling in hypertrophic scars via exon skipping
Rajiv Raktoe, MScLUMC, Dermatology, the Netherlands
Hypertrophic scars (HTS) cause both functional and aesthetic problems. HTS’s are characterized by abundant presence of myofibroblasts, which contribute to excessive production of extracellular matrix (ECM). The TGF-β signalling plays a key role in the differentiation and activity of myofibroblasts. Previous studies have shown that inhibition of TGF-β receptors in fibrotic diseases, such as Dupuytren's disease, results in a significant reduction of the fibrotic load. Furthermore, it is warranted to investigate the effect of TGF-β receptor inhibition on the different fibroblast subpopulations in HTS. It has been proposed that papillary fibroblasts, opposed to reticular fibroblasts, exhibit anti-fibrotic properties. The question is whether one could apply TGF-β receptor inhibition to induce an anti-fibrotic effect, hence improve HTS treatment.
The aims of this study are twofold; we will investigate the effects of exon skipping (ES) using antisense oligonucleotides (AON’s) to inactivate ALK5 (TGF-β receptor I) and assess the effects of ES on the different fibroblast populations in HTS.
HTS biopsies were used to set up fibroblast monocultures, contraction models (CM), fibroblast-derived matrix (FDM) and ex vivo models. In order to induce ES, AON's targeting ALK5 were supplemented to fibroblast monocultures, CM’s, FDM’s and injected into HTS ex vivo tissue. Chemical inhibition was performed using the ALK5 inhibitor SB431542.
Our data demonstrate that ALK5 inhibition affects the expression of ECM- related genes and proteins, but not fibroblast migration rate in HTS- derived monocultures. Furthermore, ES reduces contraction and affects collagen organization. Dissecting the effects of ALK5 inhibition on fibroblast subtypes, we found that ALK5 inhibition affects primarily reticular fibroblasts and myofibroblasts.
ES is a promising tool in order to modulate the TGF-β signalling pathway, the expression and rearrangement of ECM components in specific subpopulations HTS. This would open a therapeutic window for the treatment of HTS patients.
15:00 - 16:00