Abstract and Introduction
The processes behind tissue response to injury and innate immunity are integral parts of the acute wound response and the initiation of repair. In addition, inflammation is a key factor influencing both positive and negative aspects of healing in chronic wounds. Biological data on the signaling mechanisms behind these basic processes has increased dramatically over the last 10 years, yet the products and practice of wound healing have not benefited to the fullest extent from this new knowledge. An in-depth analysis of the biological mechanisms underpinning the processes that impact healing was undertaken to discover ways this information might be used to improve the treatment of chronic wounds. A synopsis of findings is presented regarding the biological mechanisms at work in injury and inflammation. It examines the early stages of wound healing from a mechanistic, biological perspective to gain insight into how this information might translate to the better use and development of wound healing products. These biological processes can impact the effectiveness of treatment from wound bed preparation to potentially regenerative products like growth factors and bioengineered skin constructs. The authors conclude that approaching wound healing from the perspective of biological mechanism can improve how effectively wounds are treated today. As importantly, viewing the development of wound care and wound healing products from the perspective of biological mechanism can lead to new ways of treating wounds that achieve greater clinical significance.
The scientific understanding of wound healing has advanced significantly over the last 20 years. In the last 5 to 10 years alone, the biology of inflammation, repair, and regeneration has been advanced by the tremendous effort to understand factors and signaling mechanisms involved in inflammation, angiogenesis, and cell proliferation--particularly as they relate to cancer progression[1,2,3] and cardiovascular disease.[4,5,6] While cutaneous healing research has certainly contributed to this body of information,[7,8] product development and clinical practice has not benefitted from recent advances in the scientific understanding of these processes as much as it could have benefitted. An extensive review and analysis of the available biological data regarding the biological mechanisms and the relationships between biological processes that could impact wound repair was undertaken. Presented is a synopsis of findings regarding the role of injury and innate immunity and how each has the potential to impact healing and the practice of wound care.
The difficulty in dissecting cutaneous healing has always been compounded by the fact that the biological processes are being carried out in an environment where physical factors can have almost as much impact as physiological factors. There is no doubt that practically speaking, the management of the physical environment, (ie, a moist healing environment, control of wound exudate, and control of bacterial contamination), has an impact on healing. For normal acute healing, this management may be all that is necessary to enable an optimum outcome. However, chronic wound conditions like a chronic venous ulcer or a hard to heal diabetic foot ulcer can be biologically and physiologically far removed from the norm. While environmental conditions are still a factor, they are more likely to be superseded by underlying pathological processes in these cases. To significantly improve healing in chronic wounds requires going beyond the physical environment to address the biological mechanisms affected by the pathological causes of tissue failure and ultimately, the inadequate response mechanisms that undermine the ability to heal. In the chronic wound, the interaction and relationship of the biological processes of repair and regeneration are more likely to be the final arbiters of success for any treatment regimen or therapeutic product.
Although the response mechanisms of the chronic wound may be altered, the native processes and biological relationships between them still serve as the foundation for cellular behavior and interaction. This synopsis focuses on the biological mechanisms underlying the acute injury and innate immune responses. The analysis draws from available knowledge of injury and inflammatory signaling and cell response. The mechanisms concerned with injury and inflammation and how they impact the biological goals of wound repair are examined. Examples are given to illustrate ways in which a biological perspective can affect how one might view and ultimately treat wounds in different situations.
Wounds. 2007;19(4):87-96. © 2007 Health Management Publications, Inc.
Cite this: The Biological Mechanisms Behind Injury and Inflammation: How They Can Affect Treatment Strategy, Product Performance, and Healing - Medscape - Apr 01, 2007.