Hyaluronic acid in incision wound fluid: a clinical study with the Cellstick device in children

Occlusive dressing-induced secretomes influence the migration and proliferation of mesenchymal stem cells and fibroblasts differently

Background

Fingertip injuries treated with occlusive dressings (ODs) lead to nearly scar-free, functionally, and aesthetically pleasing results. We hypothesized that paracrine factors in the wound fluid (secretome) may influence migration and proliferation of mesenchymal stem cells (MSCs) and fibroblasts and modulate the wound-healing process.

Methods

We could collect wound fluid samples from 4 fingertip injuries and 7 split skin donor sites at the 5th day during dressing change. Blood serum samples served as controls. The proliferation rate of MSCs and fibroblasts (HS27) was continuously measured through impedance analysis for 60 h and by Alamarblue analysis after 72 h. Cell migration was evaluated continuously for 15 h and confirmed by the in vitro wound-healing assay.

Results

Migration of MSCs under the influence of both wound fluids was significantly faster than controls from 4 to 6 h after incubation and reversed after 9 h. MSC proliferation in wound fluid groups showed a significant increase at 5 and 10 h and was significantly decreased after 45 h. Fibroblasts in wound fluid groups showed overall a significant increase in migration and a significant decrease in proliferation compared to controls.

Conclusion

OD-induced secretomes influence MSCs and fibroblasts and thereby possibly modulate wound healing and scar tissue formation.

Quantification and Stratification: Wound Research in the Future

Advances in wound healing have been slow—from the realization of a concept through to its adoption into clinical practice. There are well-known and understood reasons for this conservative approach. One less well-tried thought is to stratify the patient’s physiological status with regard to the wound. This may be the key to quantify changes in wound milieu and therefore to progress.

Prospective study on burns treated with Integra®, a cellulose sponge and split thickness skin graft: comparative clinical and histological study--randomized controlled trial

BACKGROUND

The aim of this study was to compare three different methods to cover excised burn wounds in a randomized controlled trial.

METHODS

Fascially excised burn wounds, measuring 10 cm × 5 cm, were covered with Integra(®), split thickness skin graft (STSG), and a viscose cellulose sponge Cellonex™ in each of ten adult patients. Integra(®) and Cellonex™ treated areas were covered with thin STSG on day 14. Biopsies were taken 3, 7, 14, and 21 days, 3 months, and 12 months after surgery, and samples were subjected to a range of immunohistochemical stains, in addition to hematoxylin and eosin (HE). Scar assessment was performed 3 and 12 months post-operatively with the Vancouver Scar Scale (VSS).

RESULTS

Inflammation was not substantial in any of the study areas, but Cellonex™ had the most neutrophils, histiocytes, and lymphocytes with significant differences on days 7 and 14. Complete vascularization of Integra(®) seemed to occur later compared to the other materials. STSG had the most myofibroblasts on day 14 (p = 0.012). In VSS the quality of the scar improved in all materials from 3 to 12 months.

CONCLUSIONS

The final results for all treatments after 12 months demonstrate equal clinical appearance, as well as histological and immunohistochemical findings.

Hydroxyapatite coating of cellulose sponges attracts bone-marrow-derived stem cells in rat subcutaneous tissue

The presence of bone-marrow-derived stem cells was investigated in a wound-healing model where subcutaneously implanted cellulose sponges were used to induce granulation tissue formation. When cellulose was coated with hydroxyapatite (HA), the sponges attracted circulating haemopoietic and mesenchymal progenitor cells more efficiently than uncoated cellulose. We hypothesized that the giant cells/macrophages of HA-coated sponges recognize HA as foreign material, phagocyte or hydrolyse it and release calcium ions, which are recognized by the calcium-sensing receptors (CaRs) expressed on many cells including haemopoietic progenitors. Our results showed, indeed, that the HA-coated sponges contained more CaR-positive cells than untreated sponges. The stem cells are, most probably, responsible for the richly vascularized granulation tissue formed in HA-coated sponges. This cell-guiding property of HA-coated cellulose might be useful in clinical situations involving impaired wound repair.

Extracellular matrix metabolites as potential biomarkers of disease activity in wound fluid: lessons learned from other inflammatory diseases?

The new era of pharmacogenetics has identified a potential for individuals to receive customized treatments for a variety of disease states. For such individualized treatments to fulfil their potential, it will be essential for clinicians to be able to monitor disease activity, ideally in a rapid, noninvasive fashion. The accessibility of the skin offers much potential to develop noninvasive tests of metabolic and disease activity for clinical use. Impaired human wound healing in the skin is a chronic inflammatory disorder in which the development of such tests has considerable potential, aiding clinical decision making and monitoring responses to treatment. This review article discusses how studies in other human diseases have highlighted potential biochemical markers (biomarkers) of disease activity in secreted biofluids, as aids to determining disease and metabolic activity within tissues. Using, as examples, lessons learned in the study of disease activity and prognosis of other chronic inflammatory conditions, such as osteoarthritis and periodontal disease, this review highlights the potential of dermal extracellular matrix (ECM) components (collagens, proteoglycans, hyaluronan and glycoproteins) for such uses. The limitations of currently utilized techniques and the concept that analysis of ECM components in wound fluid may represent useful biomarkers of disease activity are also discussed.