bromochloroacetic-acid and Leg-Ulcer

Ideally tissue-engineered products should maintain the characteristics of the original tissue. For example, skin represents orthokeratinized epithelium and oral gingiva represents parakeratinized epithelium. The aim of this study was to develop an autologous full-thickness gingiva substitute suitable for clinical applications and to compare it with our autologous full-thickness skin substitute that is routinely used for healing chronic wounds. Autologous full-thickness skin and gingiva substitutes were constructed under identical culture conditions from 3-mm punch biopsies isolated from the upper leg or gingiva tissue, respectively. Both consisted of reconstructed epithelia on acellular dermis repopulated with fibroblasts. To compare the characteristics of the original and reconstructed tissue, differential morphological observations and expression of differentiation markers (keratins 6, 10, and 17 and stratum corneum precursors involucrin, loricrin, and SKALP) were determined. Skin and gingiva substitutes were transplanted onto therapy-resistant leg ulcers or tooth extraction sites in order to determine their effects on wound healing. The tissue-engineered constructs maintained many of the differential histological and immunohistochemical characteristics of the original tissues from which they were derived. The skin substitute was orthokeratinized, and the gingiva substitute was parakeratinized. Transplantation of skin (n = 19) and gingiva substitutes (n = 3) resulted in accelerated wound healing with no adverse effects. As identical culture systems were used to generate both the skin and gingiva substitutes, the differences observed in tissue (immuno)histology can be attributed to intrinsic properties of the tissues rather than to environmental factors (e.g., air or saliva). This study emphasizes the importance of closely matching donor sites with the area to be transplanted. Our results represent a large step forward in the area of clinical applications in oral tissue engineering, which have until now greatly lagged behind skin tissue engineering.

Topics: Cells, Cultured; Gingiva; Gingival Diseases; Humans; Keratins; Ki-67 Antigen; Leg Ulcer; Organ Size; Organ Specificity; Pilot Projects; Salvage Therapy; Skin, Artificial; Tissue Distribution; Tooth Extraction; Transplantation, Autologous; Wound Healing

Topics: Administration, Cutaneous; Dermatologic Agents; Female; Gels; Humans; Keratins; Leg Ulcer; Middle Aged; Pyoderma Gangrenosum; Remission Induction; Skin; Treatment Outcome; Wound Healing

Chronic venous leg ulcers (VLU), especially long-lasting non-healing ulcers, are among the risk factors for squamous cell carcinoma (SCC). Malignant transformation of a VLU is a rare finding and the relative risk of carcinomatous transformation is quite low (about 5.8). SCC arising in the context of a VLU has a particularly aggressive behavior. A 76-year-old male patient with no relevant medical familial history, with chronic venous insufficiency CEAP C6 for 10 years [recurrent leg ulcers with favorable outcome (healing) after specific local and systemic treatment], showing for about three years one ulcerated lesion located on the anterior upper third of the right calf non-responsive to specific treatment, which subsequently increased their size and merged. Biopsy sample was taken. Histopathology showed epidermal acanthosis, papillomatosis, intense parakeratosis, pseudoepitheliomatous hyperplasia, dysplasia and moderately differentiated squamous cell carcinoma with areas of acantholysis. Immunohistochemistry (Ki67, EMA, cytokeratin 34βE12 and p63) was performed and all types of immunostaining were moderately to intense positive. Above-knee leg amputation and specific oncologic treatment were proposed as possible curative solutions but the patient refused. Ten months after diagnosis and discharge form the Department of Dermatology, the patient died. Patients with chronic venous leg ulcers and clinically suspicious lesions should be evaluated for malignant transformation of the venous lesion. When diagnosed, malignancy complicating a chronic venous leg ulcer requires a resolute treatment as it may be fatal.

Topics: Aged; Amputation, Surgical; Carcinoma, Squamous Cell; Cell Transformation, Neoplastic; Fatal Outcome; Humans; Immunohistochemistry; Keratins; Ki-67 Antigen; Leg; Leg Ulcer; Male; Mucin-1; Risk Factors; Skin Neoplasms; Transcription Factors; Tumor Suppressor Proteins; Varicose Ulcer

The effects of growth factors on wound healing have been studied extensively; however epidermal regeneration is not fully understood. We treated eight patients with leg ulcers with recombinant human epidermal growth factor (rhEGF) and compared biopsies of regenerating epidermis with those of controls who did not receive rhEGF. We used immunohistochemistry to identify cells expressing keratin 19 and beta1 integrin in regenerated epidermis from patients and controls. Patients treated with rhEGF had stem cells in the spinous and granular layers of regenerated epidermis. Histological analysis showed that these stem cells had reverted from differentiated to undifferentiated stem cells. Our findings provide evidence for epidermal cell reversion.

Topics: Adult; Case-Control Studies; Cell Differentiation; Epidermal Growth Factor; Humans; Integrin beta1; Keratins; Leg Ulcer; Skin; Stem Cells; Wound Healing

Twenty adult individuals with chronic leg ulcers caused by venous insufficiency, and 5 patients with full-thickness burns were treated. Twenty of the patients (15 with leg ulcers and 5 with burns) were grafted with separated autologous keratinocytes. In these cases the cells were fixed to the wound bed by a fibrin net. Five other patients (with leg ulcers) were treated with fibrin without keratinocytes. In 16 of the 20 patients grafted with keratinocytes in a fibrin net, the defect healed completely in 14 to 21 days. On the other hand, the fibrin net without keratinocytes failed to significantly accelerate the process of reepithelialization. Our experience suggests that a rapid healing of full-thickness skin defects can be achieved through keratinocyte grafting.

Topics: Burns; Epidermal Cells; Humans; Keratins; Leg Ulcer; Transplantation, Autologous

Human epidermal keratinocytes now can be grown reliably and reproducibly in vitro to form multilayered epithelium. These sheets of cultured keratinocytes have been used successfully to autograft patients with severe burns, leg ulcers and following excision of extensive congenital naevi. Whilst the technique carries the obvious advantage of huge expansion of the initial skin biopsy, thus removing the need for painful and slow healing donor sites, problems have been encountered. The take rate has been lower than with conventional split skin grafts. The take rate can be increased by the provision of a dermis. This may be achieved by providing an allodermis or by the use of a highly meshed autologous split skin graft. The wound is then covered with autologous cultured keratinocyte grafts. Manufactured dermis has been under investigation for some years and animal work suggests this may be an alternative approach. There is a delay of 2 to 3 weeks for culture of the autologous sheets of keratinocytes. This has led to the use of allogeneic grafts in a number of patients. The long term survival of these grafts has been attributed to the loss of antigen presenting cells during tissue culture. However some grafts have been rejected. Studies currently in progress may help resolve these anomalies. Whilst a number of problems remain to be solved the technique of cultured keratinocyte grafting takes wound care into an exciting new era. Skin banks may now become more than a surgeon's dream.

Topics: Bandages; Biological Dressings; Burns; Cells, Cultured; Epidermal Cells; Graft Survival; Humans; Keratins; Leg Ulcer; Methods; Transplantation, Autologous

Cultured keratinocytes were used as allografts to treat 51 patients with chronic venous ulceration or rheumatoid ulcers unresponsive to all previous conventional treatments including split skin grafts. Although early epithelialization could be seen in the centre of some ulcers, a major effect appeared to be healing from the previously indolent edge. This treatment appears to provide some clinical benefit in healing of chronic ulceration.

Topics: Aged; Aged, 80 and over; Arthritis, Rheumatoid; Bandages; Biological Dressings; Cells, Cultured; Chronic Disease; Epidermal Cells; Female; Humans; Keratins; Leg Ulcer; Male; Middle Aged; Skin Transplantation; Transplantation, Homologous; Venous Insufficiency

Topics: Candida; Culture Media; Fusarium; Histological Techniques; Humans; Keratins; Keratitis; Leg Ulcer; Plants, Edible; Skin; Temperature; Triticum; Water

Topics: Adolescent; Child; Drug Therapy; Geriatrics; Griseofulvin; Keratins; Leg Ulcer; Neurodermatitis; Pharmacology; Psoriasis; Tinea