The use of human deceased donor skin allograft in burn care

Burns are tissue wounds caused by thermal, electrical, chemical cold or radiation injuries. Deep injuries lead to dermal damage that impairs the ability of the skin to heal and regenerate on its own. Skin autografting following burn excision is considered the current gold standard of care, but lack of patient’s own donor skin or unsuitability of the wound for autografting may require the temporary use of dressings or skin substitutes to promote wound healing, reduce pain, and prevent infection and abnormal scarring. These alternatives include deceased donor skin allograft, xenograft, cultured epithelial cells and biosynthetic skin substitutes. Allotransplantation is the transplantation of cells, tissues, or organs, sourced from a genetically non-identical member of the same species as the recipient. Human deceased donor skin allografts represent a suitable and much used temporizing option for skin cover following burn injury. The main advantages for its use include dermoprotection and promotion of reepithelialisation of the wound and their ability to act as skin cover until autografting is possible or re-harvesting of donor sites becomes available. Disadvantages of its use include the limited abundance and availability of donors, possible transmission of disease, the eventual rejection by the host and its handling storing, transporting and associated costs of provision. This paper will explore the role of allograft skin in burn care, defining the indications for its use in burn management and the future potential for allograft tissue banking.     

Clinical trials of amniotic membranes in burn wound care

Four test conditions of increasing complexity were used to evaluate the clinical efficacy of amniotic membranes as biologic dressings on donor sites and burn wounds in children. These were the clean-skin donor-site wound, the uncontaminated shallow partial-thickness burn wound, the bed of freshly excised full-thickness wounds, and the granulating surface of colonized burn wounds. The rate of epithelialization under amniotic membranes was the same as that under 5% scarlet red ointment or 0.5% silver nitrate solution dressings. Preservation of a healthy excised wound bed and maintenance of a low bacterial count in contaminated wounds paralleled the experience with human allograft dressings despite technical difficulties and the absence of vascularization of amniotic membrane and its fragile structure. Tentative conclusions are drawn as to the mechanisms by which biologic dressings exert their beneficial effects.     

ABCB5+ mesenchymal stromal cells facilitate complete and durable wound closure in recessive dystrophic epidermolysis bullosa

Background and aimsRecessive dystrophic epidermolysis bullosa (RDEB) is a hereditary, rare, devastating and life-threatening skin fragility disorder with a high unmet medical need. In a recent international, single-arm clinical trial, treatment of 16 patients (aged 6–36 years) with three intravenous infusions of 2 × 10⁶ immunomodulatory ABCB5⁺ dermal mesenchymal stromal cells (MSCs)/kg on days 0, 17 and 35 reduced disease activity, itch and pain. A post-hoc analysis was undertaken to assess the potential effects of treatment with ABCB5⁺ MSCs on the overall skin wound healing in patients suffering from RDEB.MethodsDocumentary photographs of the affected body regions taken on days 0, 17, 35 and at 12 weeks were evaluated regarding proportion, temporal course and durability of wound closure as well as development of new wounds.ResultsOf 168 baseline wounds in 14 patients, 109 (64.9%) wounds had closed at week 12, of which 63.3% (69 wounds) had closed already by day 35 or day 17. Conversely, 74.2% of the baseline wounds that had closed by day 17 or day 35 remained closed until week 12. First-closure ratio within 12 weeks was 75.6%. The median rate of newly developing wounds decreased significantly (P = 0.001) by 79.3%.ConclusionsComparison of the findings with published data from placebo arms and vehicle-treated wounds in controlled clinical trials suggests potential capability of ABCB5⁺ MSCs to facilitate wound closure, prolongate wound recurrence and decelerate formation of new wounds in RDEB. Beyond suggesting therapeutic efficacy for ABCB5⁺ MSCs, the analysis might stimulate researchers who develop therapies for RDEB and other skin fragility disorders to not only assess closure of preselected target wounds but pay attention to the patients’ dynamic and diverse overall wound presentation as well as to the durability of achieved wound closure and the development of new wounds.Trial registrationClinicaltrials.gov NCT03529877; EudraCT 2018-001009-98.     

Cadaver skin allograft may improve mortality rate for burns involving over 30% of total body surface area: a propensity score analysis of data from four burn centers

Cadaver skin is used for temporary wound covering, but there is insufficient evidence regarding its clinical usefulness in patients with major burns. We aimed to analyze the effect of cadaveric skin allograft on mortality rates in patients with burns involving >?30% of total body surface area (TBSA). Our study included 1282 patients with >?30% of TBSA burned admitted to four hospitals in Korea between June 1, 2008 and December 31, 2016. Of these, 698 patients underwent cadaver skin allograft (cadaver group), and 584 were treated with conventional treatment (non-cadaver group). We corrected the differences between the two groups using propensity score matching, and generated 474 propensity score-matched pairs. Overall 90-day in-hospital mortality rate among all patients was 35.3% (453/1282). There was a significant difference in 90-day in-hospital mortality between the two groups for both unmatched [cadaver vs. conventional, 31.7 vs. 39.7%; difference, 8.0; 95% confidence interval (CI) 2.8–13.3] and propensity-matched groups (37.8 vs. 47.3%; difference, 9.5; 95% CI 3.2–15.8). Logistic regression analyses showed a significant association between cadaver skin allograft and lower 90-day in-hospital mortality in the propensity-matched groups (odds ratio, 0.42; 95% CI 0.29–0.62). Patients with major burns who underwent cadaver skin allograft had a lower mortality rate compared to those who did not. Cadaver skin allograft may improve the survival of patients with major burns, especially in the early phase of injury.     

Pyocyaneus infection of burn wounds]

Materials of clinico-bacteriological study of 302 patients with thermal burns of different severity pointed to a considerable elevation of the incidence of Ps. aeruginosa isolation (in cultures) from burn wounds; the last few years it was found in about 50% of the cases. The greater frequency of Ps. aeruginosa detection correlated with the increase of the severity of the affection. By using Soviet set of 17 type agglutinating sera it was possible to type almost 90% of the Ps. aeruginosa cultures isolated from the wounds; a marked prevalence (over 70% of the strains) of cultures belonging to the serological group II was revealed. Patients admitted to the burn centre at early periods after the trauma displayed infection of the wound with the Ps. aeruginosa strain of the II serological group.     

Role for Heat Shock Protein 90α in the Proliferation and Migration of HaCaT Cells and in the Deep Second-Degree Burn Wound Healing in Mice

Inflammation, proliferation, and tissue remodeling are essential steps for wound healing. The hypoxic wound microenvironment promotes cell migration through a hypoxia—heat shock protein 90 alpha (Hsp90α)—low density lipoprotein receptor-related protein-1 (LRP-1) autocrine loop. To elucidate the role of this autocrine loop on burn wound healing, we investigated the expression profile of Hsp90α at the edge of burn wounds and found a transient increase in both mRNA and protein levels. Experiments performed with a human keratinocyte cell line—HaCaT also confirmed above results. 17-dimethylaminoethylamino-17demethoxygeldanamycin hydrochloride (17-DMAG), an Hsp90α inhibitor, was used to further evaluate the function of Hsp90α in wound healing. Consistently, topical application of Hsp90α in the early stage of deep second-degree burn wounds led to reduced inflammation and increased tissue granulation, with a concomitant reduction in the size of the wound at each time point tested (p<0.05). Consequently, epidermal cells at the wound margin progressed more rapidly causing an expedited healing process. In conclusion, these results provided a rationale for the therapeutic effect of Hsp90α on the burn wound management.     

Non-adenine based purines accelerate wound healing

Wound healing is a complex sequence of cellular and molecular processes that involves multiple cell types and biochemical mediators. Several growth factors have been identified that regulate tissue repair, including the neurotrophin nerve growth factor (NGF). As non-adenine based purines (NABPs) are known to promote cell proliferation and the release of growth factors, we investigated whether NABPs had an effect on wound healing. Full-thickness, excisional wound healing in healthy BALB/c mice was significantly accelerated by daily topical application of NABPs such as guanosine (50% closure by days 2.5–2.8). Co-treatment of wounds with guanosine plus anti-NGF reversed the guanosine-promoted acceleration of wound healing, indicating that this effect of guanosine is mediated, at least in part, by NGF. Selective inhibitors of the NGF-inducible serine/threonine protein kinase (protein kinase N), such as 6-methylmercaptopurine riboside abolished the acceleration of wound healing caused by guanosine, confirming that activation of this enzyme is required for this effect of guanosine. Treatment of genetically diabetic BKS.Cg-m+/+lepr db mice, which display impaired wound healing, with guanosine led to accelerated healing of skin wounds (25% closure by days 2.8–3.0). These results provide further confirmation that the NABP-mediated acceleration of cutaneous wound healing is mediated via an NGF-dependent mechanism. Thus, NABPs may offer an alternative and viable approach for the treatment of wounds in a clinical setting.     

The clinical laboratory assessment of vancomycin (Edicin) efficacy in treating suppurative wounds of the skin and soft tissues, burn wounds and the infectious complications of burns]

Clinical and bacteriological efficacies of vancomycin (Edicin, LEK) in the treatment of 17 patients with wound infection and 13 patients with thermal affections were studied. The clinical efficacy in the group of the patients with purulent wounds of the soft tissues amounted to 94.1 per cent and that in the patients with thermal affections was 92.3 per cent. The bacteriological effect was recorded in 86.6 per cent of the patients with purulent wounds of the soft tissues and in 69.3 per cent of the patients with burn infections. The drug intolerability was observed in two cases.     

Wound healing potential of chitosan and N-sulfosuccinoyl chitosan derivatives

Comparative study of chitosan wound healing properties and its synthesized derivatives in MC-100 gel was carried out using the model of experimental full thickness skin wounds. It was determined that N-sulfosuccinoyl chitosan derivatives added into the gel in a concentration of 0.05% possess the higher wound healing activity in comparison with other chitosan derivatives and decrease the half-healing period of wounds 2–3 times in comparison with the control.     

Role of epidermal stem cells in repair of partial-thickness burn injury after using Moist Exposed Burn Ointment (MEBO) histological and immunohistochemical study

Moist Exposed Burn Ointment (MEBO^®) is widely used topical agent applied on skin burn. This study investigated the effect of MEBO topical application on activation and proliferation of epidermal stem cells through the immunohistochemical localization of cytokeratin 19 (CK19) as a known marker expressed in epidermal stem cells. Biopsies from normal skin and burn wounds were taken from 21 patients with partial thickness burn 1, 4, 7, 14, 21, and 28 days after treatment with MEBO. Tissue sections were prepared for histological study and for CK19 immunohistochemical localization. In control skin, only few cells showed a positive CK19 immune-reaction. Burned skin showed necrosis of full thickness epidermis that extended to dermis. Gradual regeneration of skin accompanied with an enhancement in CK19 immune-reactivity was noted 4, 7, 14 and 21 days after treatment with MEBO. On day 28, a complete regeneration of skin was observed with a return of CK19 immune-reactivity to the basal pattern again. In conclusion, the enhancement of epidermal stem cell marker CK19 after treatment of partial thickness burn injuries with MEBO suggested the role of MEBO in promoting epidermal stem cell activation and proliferation during burn wound healing.     

Ex vivo-expanded highly pure ABCB5+ mesenchymal stromal cells as Good Manufacturing Practice-compliant autologous advanced therapy medicinal product for clinical use: process validation and first in-human data

Background aimMesenchymal stromal cells (MSCs) hold promise for the treatment of tissue damage and injury. However, MSCs comprise multiple subpopulations with diverse properties, which could explain inconsistent therapeutic outcomes seen among therapeutic attempts. Recently, the adenosine triphosphate-binding cassette transporter ABCB5 has been shown to identify a novel dermal immunomodulatory MSC subpopulation.MethodsThe authors have established a validated Good Manufacturing Practice (GMP)-compliant expansion and manufacturing process by which ABCB5⁺ MSCs can be isolated from skin tissue and processed to generate a highly functional homogeneous cell population manufactured as an advanced therapy medicinal product (ATMP). This product has been approved by the German competent regulatory authority to be tested in a clinical trial to treat therapy-resistant chronic venous ulcers.ResultsAs of now, 12 wounds in nine patients have been treated with 5 × 10⁵ autologous ABCB5⁺ MSCs per cm² wound area, eliciting a median wound size reduction of 63% (range, 32–100%) at 12 weeks and early relief of pain.ConclusionsThe authors describe here their GMP- and European Pharmacopoeia-compliant production and quality control process, report on a pre-clinical dose selection study and present the first in-human results. Together, these data substantiate the idea that ABCB5⁺ MSCs manufactured as ATMPs could deliver a clinically relevant wound closure strategy for patients with chronic therapy-resistant wounds.     

Regulation of Connexin43 Gap Junction Protein Triggers Vascular Recovery and Healing in Human Ocular Persistent Epithelial Defect Wounds

Transiently blocking the expression of the gap junction protein connexin43 using antisense oligodeoxynucleotides or blocking hemichannels with connexin mimetic peptides has been shown to significantly improve outcomes in a range of acute wound models. Less is known about their likely effects in nonhealing wounds. In the eye, prolonged inflammation and lack of epithelial recovery in nonhealing corneal epithelial wounds may lead to corneal opacity, blindness or enucleation. We report here the first human applications of antisense oligodeoxynucleotides that transiently block translation of connexin43 in a prospective study of five eyes with severe ocular surface burns (persistent epithelial defects), which were unresponsive to established therapy for 7 days to 8 weeks prior to treatment. Connexin43-specific antisense oligodeoxynucleotide was delivered in cold, thermoreversible Poloxamer407 gel under either an amniotic membrane graft or a bandage contact lens. The connexin43-specific antisense application reduced inflammation within 1–2 days, and in all five eyes complete and stable corneal reepithelialization was obtained. Recovery of the vascular bed and limbal reperfusion appeared to precede corneal epithelial recovery. We conclude that connexin modulation provides a number of benefits for nonhealing ocular burn wounds, one of which is to promote vascular recovery.     

The plasminogen receptor,Plg-RKT,plays a role in inflammation and fibrinolysis during cutaneous wound healing in mice

Wound healing is a complex physiologic process that proceeds in overlapping, sequential steps. Plasminogen promotes fibrinolysis and potentiates the inflammatory response during wound healing. We have tested the hypothesis that the novel plasminogen receptor, Plg-R_KT, regulates key steps in wound healing. Standardized burn wounds were induced in mice and time dependence of wound closure was quantified. Healing in Plg-R_KT^−/− mice was significantly delayed during the proliferation phase. Expression of inflammatory cytokines was dysregulated in Plg-R_KT^−/− wound tissue. Consistent with dysregulated cytokine expression, a significant delay in wound healing during the proliferation phase was observed in mice in which Plg-R_KT was specifically deleted in myeloid cells. Following wound closure, the epidermal thickness was less in Plg-R_KT^−/− wound tissue. Paradoxically, deletion of Plg-R_KT, specifically in keratinocytes, significantly accelerated the rate of healing during the proliferation phase. Mechanistically, only two genes were upregulated in Plg-R_KT^−/− compared with Plg-R_KT^+/+ wound tissue, filaggrin, and caspase 14. Both filaggrin and caspase 14 promote epidermal differentiation and decrease proliferation, consistent with more rapid wound closure and decreased epidermal thickness during the remodeling phase. Fibrin clearance was significantly impaired in Plg-R_KT^−/− wound tissue. Genetic reduction of fibrinogen levels to 50% completely abrogated the effect of Plg-R_KT deletion on the healing of burn wounds. Remarkably, the effects of Plg-R_KT deletion on cytokine expression were modulated by reducing fibrinogen levels. In summary, Plg-R_KT is a new regulator participating in different phases of cutaneous burn wound healing, which coordinately plays a role in the interrelated responses of inflammation, keratinocyte migration, and fibrinolysis.Subject terms: Extracellular matrix, Mechanisms of disease     

Is ABO group incompatibility really the reason of accelerated failure of cryopreserved allografts in very young patients? – Echography assessment of the European Homograft Bank (EHB) cryopreserved allografts used for reconstruction of the right ventricular outflow tract<Superscript>*</Superscript>

Right ventricular outflow tract reconstruction (RVOTR) with cryopreserved allograft for Ross operation and other congenital or acquired cardiac malformation has become a routine and currently, the procedure of choice for children and young patients. A tendency of accelerated degeneration in the youngest recipients has been reported. Some authors advocate the ABO group incompatibility as the main reason for such failure. This retrospective monocentric study presents the long-term outcome of the European Homograft Bank (EHB) cryopreserved allografts, used for RVOTR in Ross operation (group one) and other congenital heart malformation-s (group two). The evaluation of the allograft performance was done by means of echography, considering the allografts with the transvalvular gradient of ≥40 mm Hg and/or regurgitation of ≥3+ as failed. Fifty-one patients of group one and 123 of group two were analysed after completed follow-up information. About 25.5% of patients of group one and 30.8% of group two had a compatible, whereas 74.5% of group one and 68.92 of group two an incompatible ABO group with the donor. The mean follow up was 45.77 and 68.88 months, respectively. In second group 22.76% received the aortic, while 77.24% pulmonary allograft. Only three cases of group one (5.88%) failed: one with a compatible (7.69%) and two with an incompatible ABO group (5.26%) (p = 0.1), whereas 39 patients (29.4%) of group two failed between 20.1 and 120.2 months (29.73% with and 29.07% without ABO compatibility, p = 0.03). Contrary, the age showed more importance in the allograft failure: out of 41 failed allografts, 24 (58.54%) were implanted in patients of 0–5 years (9 or 37.5% with compatible and 15 or 62.5% with incompatible ABO group). Generally, analysing both groups together, there was no influence of ABO mismatching on the allograft failure (p = 0.79). Contrary, there was a significant difference in survival between Ross and non-Ross group (p = 0.00082). This revised version was published online in July 2006 with corrections to the Cover Date.     

Thymosin beta 4 improves dermal burn wound healing via downregulation of receptor of advanced glycation end products in db/db mice

BackgroundThe delay of dermal burn wound healing caused by vascular disorders is a critical problem for many diabetic patients. Thymosin β₄ (Tβ₄), identified by subtractive cloning of endothelial cells on plastic versus basement membrane substrates, has been found to promote angiogenesis and dermal wound repair in rats, aged mice, and db/db diabetic mice. However, previous studies involving the role of Tβ₄ in wound repair were limited to mechanical damage and dermal impairment. Thus, this study aimed to evaluate the improvement of healing of burn wounds by Tβ₄ in relation to advanced glycation end products (AGE), which are pathological factors in diabetes.MethodsWe adapted a dermal burn wound in vivo model in which the dorsal skin of db/db mice was exposed for 10 s to 100 °C heated water to produce a deep second-degree burn 10 mm in diameter. Five mg/kg of Tβ₄ was then injected intradermally near the burn wound twice a week for 2 weeks.ResultsAfter treatment, Tβ₄ improved wound healing markers such as wound closure, granulation, and vascularization. Interestingly, Tβ₄ reduced levels of receptor of AGE (RAGE) during the wound healing period.ConclusionsTβ₄ exerts effects to remedy burn wounds via downregulation of RAGE.General significanceOur results suggest the potential importance of Tβ₄ as a new therapy for impaired burn wound healing that is associated with diabetes.     

The Spatial Distribution of Fungi on Decomposing Woody Litter in a Freshwater Stream,Western Ghats,India

We mapped filamentous fungal association with mechanically “hard” and “soft” woody litter naturally deposited in a stream of the Western Ghats of India. Using a durometer (rubber hardness tester), the toughness of surface of wood collected from stream was determined by considering durometer reading from 60–72 to 30–37 as hardwood and softwood, respectively. From each wood (1.5 cm diameter), two segments each of 3 cm length were excised and vertically cut into nine sections comprising eight marginal and one central section. From three stream locations, hardwood and softwood sections were assessed for the occurrence of lignicolous and Ingoldian fungi. A first set of wood sections was incubated in damp chambers up to 4 months with periodical screening (every 2 weeks) for lignicolous fungi. Another set was incubated in bubble chambers up to 72 h to ascertain colonization of Ingoldian fungi. In hardwood sections, 17 lignicolous fungi (ascomycetes, four; mitosporic fungi, 13; mean, 6.8; range, 6–8/section) and ten Ingoldian fungi (mean, 2; range, 0–4/section) comprising nine lignicolous (11.1–40.7%) and three Ingoldian (11.1–14.8%) fungi as core-group taxa were recovered. In softwood, ten lignicolous fungi (ascomycetes, 0; mitosporic fungi, ten; mean, 3.8; range, 2–5/section) and 26 Ingoldian fungi (mean, 8.1; range, 5–10/section) comprising six lignicolous (11.1–85.2%) and 12 Ingoldian (11.1–88.9%) fungi as core-group taxa were recovered. The ratio of lignicolous fungi/Ingoldian fungi was higher in hardwood than softwood (1.7 vs. 0.4). The spore output of Ingoldian fungi was higher in softwood (mean, 901 g⁻¹; range, 80–2546 g⁻¹) than hardwood (mean, 21 g⁻¹; range, 0–140 g⁻¹). The Shannon diversity of lignicolous fungi was higher in hardwood than softwood (3.604 vs. 2.665), whereas it was opposite for Ingoldian fungi (3.116 vs. 3.918). The overall fungal diversity was higher in softwood than hardwood (4.413 vs. 4.219). The range of Jaccard’s index of similarity among wood sections was higher in lignicolous fungi (8–71% and 13–75%) than Ingoldian fungi (0–50% and 8–55%) in hardwood and softwood. The rarefaction indices of expected number of taxa against hardwood sections revealed higher and persistent lignicolous fungi than the Ingoldian fungi, while the Ingoldian fungi were persistent in softwood sections, although they were lower than lignicolous fungi. Our study demonstrated the dominance of lignicolous fungi and Ingoldian fungi in hardwood and softwood, respectively.     

Banking of osteochondral allografts, Part II. Preservation of Chondrocyte Viability During Long-Term Storage

One of the most important factors concerning the successful clinical outcome after transplantation of osteochondral allografts is the viability of the cartilage.The viability of cryopreserved cartilage is quite poor, 20–30% cell survival has been published. The purpose of this study was to develop a new storage method which improves the chondrocyte viability. The talus of cadaveric donors was used as a model tissue to compare human osteochondral allograft cartilage viability following cryopreservation with that remaining after prolonged refrigerated storage. Full-thickness cartilage punch biopsies had been cryopreserved, and tali were divided into two matched groups and stored in TCM for 60 days at +4 °C, either with or without regular medium replacement. The cartilage of each graft was biopsied and assayed for viability on every third day by the MTT reduction assay. During 4 °C storage, a recurring pattern of large fluctuations in apparent cartilage viability was observed in every stored graft, with or without medium replacement. These fluctuations did not appear in control specimens of either fresh or cryopreserved human skin that were assayed in parallel with the cartilage biopsies, so the viability fluctuation seems an intrinsic property of the cartilage in these conditions. Cartilage stored for 60 days at +4 °C showed significantly higher viability (35.2 ± 3.3 %) than fresh cartilage that had been cryopreserved (21.6 ± 1.8 %). This was true even when cryopreserved and thawed cartilage was subjected to a 3 day post thaw incubation under presumably favorable conditions (17.7 ± 1.6 %). These viability assay results, (reflective of intracellular metabolic activity), were corroborated by the fluorescent dye mixture SYTO-16 and propidium iodide. The data indicate that long-term stored refrigerated cartilage appears to retain a viability higher than that of cryopreserved cartilage for up to and perhaps beyond 60 days of storage. There was no viability index difference between the medium replaced and non-replaced groups. Although an exceptional result, in one individual case, more than 65% viable cells could be detected in the talar cartilage after 60 days storage at +4 °C. This revised version was published online in July 2006 with corrections to the Cover Date.     

Skin allograft procurement and transplantation in Mashhad,Iran: Are burn patients’ needs being met?

Only a single donor’s tissue may save or improve lives of one hundred patients. Unfortunately, low governmental and media support of tissue procurement and transplantation programs is a worldwide problem. Loss of an effective tissue procurement program in many countries like Iran, may lead to loss of many thousands valuable tissues each year. To evaluate the rate of skin donation in Mashhad in comparison to other organs and tissues, we extracted the data related to tissue and organ procurement in Mashhad from 2001. Then we evaluated the annual skin allograft needs in the Burn Department of Imam Reza Hospital as the only referral burn center in the northeast of Iran. Brain dead potential donation rate per million populations of Mashhad in the years 2007–2014 was about 33. The mean refusal rate was 51%. Of patients who have consent for donation, more than 86% have consent for skin donation. Skin allograft procured from 119 (35.5%) candidates. Average of skin retrieval per cadaveric was 1525 cm² with a gradual increase from 1400 cm² in the first year to 1800 cm² in the last year. The recipient to donor ratio was 1.14. It is estimated that about 1 cm² of skin allograft is needed for any cm² burnt body surface area. Considering more than 700 acute burn hospitalization in our burn unit, the patients need for skin allograft would be more than 3.5 million cm², annually. The annual amount of skin procurement in Mashhad has been currently about 20,000 cm². It shows that our patients demand is higher than supply. Skin procurement and transplantation is a simple procedure which can be as lifesaving as organ procurement and transplantation. But there isn’t any national organization to regulate tissue procurement, banking and transplantation. Governmental support of skin procurement and transplantation programs especially nonprofit programs may improve skin procurement rate and save more lives of severely burnt patients.     

Intra-operative washing of morcellised bone allograft with pulse lavage: how effective is it in reducing blood and marrow content?

The use of unprocessed bone carries a risk of transmission of blood borne diseases. Although models of infectivity are unproven, a theoretical risk of transmission of variant Creutzfeld-Jakob Disease, a human prion disease, exists as probable blood borne transmission has been reported in three cases. The aim of our study was to determine the effectiveness of standard operating theatre pulse lavage in removing protein, fat and double stranded Deoxyribonucleic acid (dsDNA) from morcellised bone allograft. Twelve donated femoral heads were divided into halves and milled into bone chips. One half of the bone chips were washed with pulse lavage, whereas, the other half acted as control. In order to determine the amount of protein, fat and dsDNA present in the washed and unwashed samples, a validated multistep washing protocol was used. Using the validated technique, simple intra-operative washing of morcellised unprocessed bone allograft removed a significant amount of the protein (70.5%, range: 39.5–85%), fat (95.2%, range: 87.8–98.8%) and DNA (68.4%, range: 31.4–93.1%) content. Intra-operative washing of morcellised bone allograft with pulse lavage may thereby reduce the theoretical risk of prion and other blood borne disease transmission. Combined with the known improved mechanical characteristics of washed allograft, we would recommend pulse lavage as a routine part of bone allograft preparation.