CICAFAST: comparison of a biological dressing composed of fetal fibroblasts and keratinocytes on a split-thickness skin graft donor site versus a traditional dressing: a randomized controlled trial

Current Biomaterials for Wound Healing

Wound healing is the body's process of injury recovery. Skin healing is divided into four distinct overlapping phases: hemostasis, inflammation, proliferation, and remodeling. Cell-to-cell interactions mediated by both cytokines and chemokines are imperative for the transition between these phases. Patients can face difficulties in the healing process due to the wound being too large, decreased vascularization, infection, or additional burdens of a systemic illness. The field of tissue engineering has been investigating biomaterials as an alternative for skin regeneration. Biomaterials used for wound healing may be natural, synthetic, or a combination of both. Once a specific biomaterial is selected, it acts as a scaffold for skin regeneration. When the scaffold is applied to a wound, it allows for the upregulation of distinct molecular signaling pathways important for skin repair. Although tissue engineering has made great progress, more research is needed in order to support the use of biomaterials for wound healing for clinical translation.

Hydrogel dressings for donor sites of split-thickness skin grafts

BACKGROUND

Donor site wounds of split-thickness skin grafts can be a major cause of morbidity. Choosing the appropriate dressing for these wounds is crucial to successful healing. Various types of dressing are available, including hydrogel dressings. A review of current evidence is required to guide clinical decision-making on the choice of dressing for the treatment of donor sites of split-thickness skin grafts.

OBJECTIVES

To assess the effects of hydrogel dressings on donor site wounds following split-thickness skin grafts for wound healing.

SEARCH METHODS

In July 2022 we searched the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL EBSCO Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses, and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication, or study setting.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing hydrogel dressings with other types of dressing, topical treatments or no dressing, or with different types of hydrogel dressings in managing donor site wounds irrespective of language and publication status.

DATA COLLECTION AND ANALYSIS

Two review authors independently carried out data extraction, risk of bias assessment using the Cochrane risk of bias tool, RoB 1, and quality assessment according to GRADE methodology.

MAIN RESULTS

We included two studies (162 participants) in this review. One study with three arms and 101 participants (15 months' duration) was conducted in a children's hospital, and compared hydrogel dressings in the form of Sorbact with Algisite, an alginate dressing and Cuticerin, a smooth acetate gauze impregnated with water-repellent ointment. Another study with two arms and 61 participants (19 months' duration) was conducted in three surgery departments and compared an octenidine-containing hydrogel dressing with an identical non-antimicrobial hydrogel dressing. We identified no studies that compared hydrogel dressings with another therapy such as a topical agent (a topical agent is a cream, an ointment or a solution that is applied directly to the wound), or no dressing, or a combination of hydrogel dressings and another therapy versus another therapy alone. Both studies were at high risk of attrition bias and the second study was also at unclear risk of selection bias. Amorphous hydrogel dressings versus other types of dressings Amorphous hydrogel dressings may increase time to wound healing when compared with alginate (mean difference (MD) 1.67 days, 95% confidence interval (CI) 0.56 to 2.78; 1 study, 69 participants; low-certainty evidence) or Cuticerin dressings (MD 1.67 days, 95% CI 0.55 to 2.79; 1 study, 68 participants; low-certainty evidence). The effect of amorphous hydrogel dressings compared with other types of dressings is uncertain for pain at the donor site and wound complications, including scarring and itching (very low-certainty evidence). No adverse events were reported in any of the groups. The study did not report health-related quality of life or wound infection. Octenidine-based hydrogel dressing versus octenidine-free hydrogel dressing The effect of octenidine-based hydrogel dressings versus octenidine-free hydrogel dressings is uncertain for time to wound healing (MD 0.40, 95% CI 0.28 to 0.52; 1 study, 41 participants) and wound infection, as the certainty of the evidence is very low. The certainty of the evidence is also very low for adverse events, with two participants in the intervention group and one participant in the comparison group reporting adverse events (risk ratio (RR) 0.58, 95% CI 0.06 to 5.89; 1 study, 41 participants). The study did not report donor site pain, health-related quality of life, or wound complications.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine the effect of hydrogel dressings on donor site wounds of split thickness skin grafts compared with other types of dressings. There is a need for adequately powered and well-designed RCTs, with adequate sample sizes, types of populations and subgroups, types of interventions, and outcomes, that compare hydrogel dressings with other treatment options in the treatment of donor site wounds of split-thickness skin grafts.

Retrospectives on Three Decades of Safe Clinical Experience with Allogeneic Dermal Progenitor Fibroblasts: High Versatility in Topical Cytotherapeutic Care

Allogeneic dermal progenitor fibroblasts constitute cytotherapeutic contenders for modern cutaneous regenerative medicine. Based on advancements in the relevant scientific, technical, and regulatory fields, translational developments have slowly yet steadily led to the clinical application of such biologicals and derivatives. To set the appropriate general context, the first aim of this study was to provide a current global overview of approved cell and gene therapy products, with an emphasis on cytotherapies for cutaneous application. Notable advances were shown for North America, Europe, Iran, Japan, and Korea. Then, the second and main aim of this study was to perform a retrospective analysis on the various applications of dermal progenitor fibroblasts and derivatives, as clinically used under the Swiss progenitor cell transplantation program for the past three decades. Therein, the focus was set on the extent and versatility of use of the therapies under consideration, their safety parameters, as well as formulation options for topical application. Quantitative and illustrative data were summarized and reported for over 300 patients treated with various cell-based or cell-derived preparations (e.g., progenitor biological bandages or semi-solid emulsions) in Lausanne since 1992. Overall, this study shows the strong current interest in biological-based approaches to cutaneous regenerative medicine from a global developmental perspective, as well as the consolidated local clinical experience gathered with a specific and safe allogeneic cytotherapeutic approach. Taken together, these current and historical elements may serve as tangible working bases for the further optimization of local and modern translational pathways for the provision of topical cytotherapeutic care.

Comparison of the Effect of Using Collective Plus Ag Dressing and Vaseline Gauze Dressing in the Donor of Split-Thickness Burn Grafts

Background

Skin graft involves removing a part of the skin and using it in another part of the body. One of the most common reasons for using a graft is burns. We aimed to compare the effect of Colactive plus Ag dressing with Vaseline gauze dressing in donor sites of split-thickness skin grafts of burned patients.

Methods

The present study was conducted as a randomized clinical trial (RCT) in the Motahari burn Hospital, Tehran, Iran in 1401. The sampling method was done using Cochran's formula and available patients so 15 people were enrolled. The findings of the study were collected using a researcher-made form.

Results

The average duration of recovery, the amount and intensity of pain, and the amount of itching between the two types of Colative plus Ag plus Ag dressing with Vaseline gauze are statistically significant at the 95% confidence level. (P-value<0.05). In addition, the findings showed that the average amount of scar left by the wound in the two types of dressings examined is not statistically significant at the 95% confidence level (P-value > 0.05).

Conclusion

The use of Colactive silver dressing has less pain, less itching in the donor area, and a shorter average recovery time than Vaseline gauze. The use of the Colactive plus Ag will be more effective than Vaseline gauze.

Inflammatory Microenvironment of Skin Wounds

Wound healing is a dynamic and highly regulated process that can be separated into three overlapping and interdependent phases: inflammation, proliferation, and remodelling. This review focuses on the inflammation stage, as it is the key stage of wound healing and plays a vital role in the local immune response and determines the progression of wound healing. Inflammatory cells, the main effector cells of the inflammatory response, have been widely studied, but little attention has been paid to the immunomodulatory effects of wound healing in non-inflammatory cells and the extracellular matrix. In this review, we attempt to deepen our understanding of the wound-healing microenvironment in the inflammatory stage by focusing on the interactions between cells and the extracellular matrix, as well as their role in regulating the immune response during the inflammatory stage. We hope our findings will provide new ideas for promoting tissue regeneration through immune regulation.

Immunohistochemical Analysis of Postburn Scars following Treatment Using Dermal Substitutes

Background

Post-burn hypertrophic scars commonly occur after burns. Studies that compare dermal substitutes with other treatment methods are insufficient. The purpose was to analyze the histopathological differences in hypertrophic burn scars after Matriderm®+split-thickness skin graft (STSG) and compare with AlloDerm®+STSG, STSG, full-thickness skin graft (FTSG), and normal skin.

Methods

Samples of unburned, normal skin and deep 2^nd or 3^rd degree burns were obtained from patients who experienced a burn injury in the past to at least 6 months before biopsy, which was performed between 2011 and 2012. All subjects received >6 months of treatment before the biopsy. Intervention groups were normal (63), STSG (28), FTSG (6), Matriderm® (11), and AlloDerm® (18). Immunohistochemical analyses of elastin, collagen I, collagen III, cluster of differentiation 31 (CD31), smooth muscle actin (α-SMA), and laminin from scar and control tissues were performed and compared.

Results

α-SMA vascular quantity and vessel width, stromal CD31, and basement membrane laminin expression were not significantly different between normal and intervention groups. Matriderm® group showed no significant difference in elastin, collagen III, stromal CD31 and α-SMA, CD31 vessel width, stromal α-SMA, vessel quantity and width, and laminin length compared to the normal group, meaning they were not significantly different from the normal skin traits.

Conclusion

Dermal substitutes may be an optimal alternative to address the cosmetic and functional limitations posed by other treatment methods.

Dermal Fibroblast Heterogeneity and Its Contribution to the Skin Repair and Regeneration

Significance: Dermal fibroblasts are the major cell type in the skin's dermal layer. These cells originate from distinct locations of the embryo and reside in unique niches in the dermis. Different dermal fibroblasts exhibit distinct roles in skin development, homeostasis, and wound healing. Therefore, these cells are becoming attractive candidates for cell-based therapies in wound healing. Recent Advances: Human skin dermis comprises multiple fibroblast subtypes, including papillary, reticular, and hair follicle-associated fibroblasts, and myofibroblasts after wounding. Recent studies reveal that these cells play distinct roles in wound healing and contribute to diverse healing outcomes, including nonhealing chronic wound or excessive scar formation, such as hypertrophic scars (HTS) and keloids, with papillary fibroblasts having antiscarring and reticular fibroblast scar-forming properties. Critical Issues: The identities and functions of dermal fibroblast subpopulations in many respects remain unknown. In this review, we summarize the current understanding of dermal fibroblast heterogeneity, including their defined cell markers and dermal niches, dynamic changes, and contributions to skin wound healing, with the emphasis on scarless healing, healing with excessive scars (HTS and keloids), chronic wounds, and the potential application of this heterogeneity for developing cell-based therapies that allow wounds to heal faster with less scarring. Future Directions: Heterogeneous dermal fibroblast populations and their functions are poorly characterized. Refining and advancing our understanding of dermal fibroblast heterogeneity and their participation in skin homeostasis and wound healing may create potential therapeutic applications for nonhealing chronic wounds or wounds that heal with excessive scarring.

Holistic Approach of Swiss Fetal Progenitor Cell Banking: Optimizing Safe and Sustainable Substrates for Regenerative Medicine and Biotechnology

Safety, quality, and regulatory-driven iterative optimization of therapeutic cell source selection has constituted the core developmental bedrock for primary fetal progenitor cell (FPC) therapy in Switzerland throughout three decades. Customized Fetal Transplantation Programs were pragmatically devised as straightforward workflows for tissue procurement, traceability maximization, safety, consistency, and robustness of cultured progeny cellular materials. Whole-cell bioprocessing standardization has provided plethoric insights into the adequate conjugation of modern biotechnological advances with current restraining legislative, ethical, and regulatory frameworks. Pioneer translational advances in cutaneous and musculoskeletal regenerative medicine continuously demonstrate the therapeutic potential of FPCs. Extensive technical and clinical hindsight was gathered by managing pediatric burns and geriatric ulcers in Switzerland. Concomitant industrial transposition of dermal FPC banking, following good manufacturing practices, demonstrated the extensive potential of their therapeutic value. Furthermore, in extenso, exponential revalorization of Swiss FPC technology may be achieved via the renewal of integrative model frameworks. Consideration of both longitudinal and transversal aspects of simultaneous fetal tissue differential processing allows for a better understanding of the quasi-infinite expansion potential within multi-tiered primary FPC banking. Multiple fetal tissues (e.g., skin, cartilage, tendon, muscle, bone, lung) may be simultaneously harvested and processed for adherent cell cultures, establishing a unique model for sustainable therapeutic cellular material supply chains. Here, we integrated fundamental, preclinical, clinical, and industrial developments embodying the scientific advances supported by Swiss FPC banking and we focused on advances made to date for FPCs that may be derived from a single organ donation. A renewed model of single organ donation bioprocessing is proposed, achieving sustained standards and potential production of billions of affordable and efficient therapeutic doses. Thereby, the aim is to validate the core therapeutic value proposition, to increase awareness and use of standardized protocols for translational regenerative medicine, potentially impacting millions of patients suffering from cutaneous and musculoskeletal diseases. Alternative applications of FPC banking include biopharmaceutical therapeutic product manufacturing, thereby indirectly and synergistically enhancing the power of modern therapeutic armamentariums. It is hypothesized that a single qualifying fetal organ donation is sufficient to sustain decades of scientific, medical, and industrial developments, as technological optimization and standardization enable high efficiency.