Author: Anoma Ranaweera B.V. Sc; PhD (Clinical Biochemistry, University of Liverpool, UK), 2013.
Keratin dressings release keratin peptides into the wound. These activate keratinocytes (skin cells) in the wound bed, stimulating them to proliferate and leading to healing of the wound. Keratin dressings have been reported to reduce the total cost of care and improve quality of life.
Many wounds remain unhealed despite optimal standard care. For example, in the US, standard care of diabetic foot ulcers leads to healing of less than one-third of patients in 20 weeks. More than 25 per cent of venous leg ulcers remains unhealed, even after six months of therapy.
In chronic wounds, there is a failure of the normal healing processes, which include haemostasis (blood clotting), inflammation, the formation of granulation tissue and re-epithelisation of the skin surface.
The role of keratin in wound healing is under investigation. Traditionally, keratin has been viewed as purely a physical structure protecting the skin. However, we now know keratin proteins are also vitally important for normal wound healing.
Keratins (KRTs) are a family of epidermal proteins produced by cells called keratinocytes. They are present in skin, hair and nails. Keratin is an important component of skin barrier function.
Keratin gene expression demarcates three keratinocyte phenotypes:
The activated or functional keratin has bioactive properties that enhance wound healing. Wound healing begins with the migration of keratinocytes at the edge of the wound towards the wound bed. This leads to the next stages of wound healing: proliferation and migration of fibroblasts, production of collagen and formation of granulation tissue.
Keratinocytes are not activated in non-healing chronic wounds.
Keratin dressings may be used to help heal a variety of wounds and ulcers. For example:
Keratin protein extracted from New Zealand sheep wool has been used to make wound dressings by Keraplast Technologies, LLC, San Antonio, Texas, USA (May 2013). Replicine™ Functional Keratin® advanced wound dressings are approved by the US FDA, European Union, Australian and New Zealand regulatory authorities.
Keratin dressings are available in different forms for different types of wound.
No controlled clinical trials of keratin wound dressings have been reported to date. Available data are based on case series.
Clinical evaluations of keratin dressings for chronic wound care conducted at the Nurse Maude Wound Clinic, at Christchurch in New Zealand, have shown a reduction in wound size, confirmed by planimetry and wound photography, in a variety of problematic, non-healing chronic wounds.
The following recommendations come from the manufacturer of keratin-based dressings.
To date, no adverse effects have been reported from keratin dressings. They are well tolerated by host tissues and do not provoke immune reactions.
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