Tissue and organ failure caused by burns and other types of injury on the human skin poses a major health problem, which has affected millions of people in the world throughout human history (Niklason and Langer 303). Burns is especially one of the major and most common causes of tissue and organ failure involving the skin. It is estimated that this problem accounts for about half of the total annual expenditure of healthcare in most countries, including the US. Currently, several options are available to treat tissue and organ failure resulting from major burns. For instance, surgical repair, drug therapy, transplantation (such as human or xenotransplantation), mechanical devices, and prostheses are available for application (Priya, Jungvid, and Ashok 105). Although these techniques have been used over time, they are less effective in managing the problem, especially in cases where the skin tissue or organ cannot be repaired or where long-term recovery cannot be achieved satisfactorily due to the extent of the burn (Pomahač ert al. 334). In fact, these methods cannot produce effective and satisfactory results in replacing the tissue (Lanza, Langer and Vacanti 123).
These problems call for a better and more effective method or techniques for providing remedies to patients with extensive tissue and organ burns involving the skin (Lutolf and Hubbell 48). Tissue engineering has emerged as a significant and potential technique that provides humans with a complementary or alternative solution to the problem (Lee and Mooney 1882). In this case, tissue engineering seeks to address the problem of organ and tissue failure through the provision of a better and more effective technique such as natural implants, organ mimics that are functional from the beginning, organ mimics that grow towards full functionality, synthetic and semi-synthetic tissue grafting (Metcalfe and Ferguson 413). Previously, biomedical engineering focused on skin equivalents needed to treat major skin burns. However, there is an increasing trend towards developing tissue types through bioengineering, biomaterials, and scaffolds. They are increasingly being used as delivery systems (Eaglstein and Falanga 902). In modern times, several approaches are being used to make both differentiated and undifferentiated cells grow and develop into functional cells of a particular type in order to replace the damaged cells and their functionality on the skin (Bianco and Robey 118). Stem cells, for instance, have provided biomedical science with a potential source of cells that can easily be coaxed into a variety of functional cells because they are both pluripotent and portipotent (Hubbell 556).
The procedure is relatively complicated, but the desired and effective results are usually achieved. Both epidermal and dermal tissues of the skin are used in the materials and methods part of the procedure. Epidermal substitutes are used for treating lesions that have affected the dermis. They contain autologous keratinocytes that are obtained and cultured in cell cultures in the laboratory and in the presence of murine fibroblasts (Horch 599). First, a skin biopsy extending some 2 to 5 cm2 is obtained. Secondly, the dermis and epidermis tissues sections are separated from each other. Third, the keratinocytes are isolated and cultured, which takes about 3 weeks to culture in an appropriate medium (Bartholomew et al. 45). Since this time is relatively long, the patient must be treated with a temporary dressing to protect the wounds and the tissues involved and stimulate their healing process. However, current technologies allow for direct spraying of the biopsy cells directly into the wound, which makes it possible for local delivery of the cells. However, this technique is not recommended for third-degree burn wounds. Recent techniques have made it possible to treat third-degree wounds within a short time through application of cultured keratinocytes. For instance, surface-functionalized polymer discs make it possible for the delivery of cultured autologous keratinocytes directly into chronic and third-degree wounds (Pham, Sharma and Mikos 1198).
Another method of isolation involves dermal substitutes as compared to epidermal substitutes. To treat full-thickness lesions that affect both the dermis and the epidermis. The use of an allograft or dermal constructs is necessary for these situations. Dermal substitutes are developed through natural or synthetic techniques. They tend to prevent the contraction of the wound and provide mechanical stability. For instance, the process involves engineering tissues using such procedures as loading dermal substitutes with complexes of plasmid DNA that encodes for VEGF-165/N,N,N-trimethyl chotisan chloride (Cancedda et al. 83). Testing for regeneration of the full-thickness wounds in animal models as well as in humans has shown that the process is faster and more effective, making it an important approach to healing these wounds (MacNeil 876).
A number of parameters need to be considered in the process of developing and using these techniques to heal skin wounds. For instance, poor performance and prohibitive costs have affected the development and applicability of tissue engineering techniques and approaches. In addition, the delicate nature of the biomedical engineering techniques involved is worth consideration as a parameter of interest. For instance, obtaining stem cell lines that are able to differentiate into the specific cells for specific tissues has been a limiting factor (Dai et al. 4266). In addition, the processes involved are not only costly, but also laborious and require advanced technologies to complete with success.
These parameters can be related to tissue replacement in biomedical engineering. For instance, enhanced technologies and knowledge in stem cell therapy have made it possible to develop recombinant DNA technologies that improve the way cells can be enticed to grow into specific cell lines for specific tissues. In this case, gene manipulation makes it possible to coax keratinocyte cell lines to differentiate into specific dermal or epidermal cells for skin grafting (Fauza 358).
Observations from these techniques and approaches indicate that the future of the skin grafting approaches is better if the current techniques and research are enhanced (Martin, Wendt and Heberer 87). Specifically, authorization of stem cell research is needed to ensure that biomedical scientists have the freedom to use various cell lines to improve the approaches to skin tissue and organ grafting (Langer 98). However, these results have a number of limitations. For instance, stem cell research is in itself costly and unpredictable, given that some laws and regulations limit the amount and nature of research that can be done with these cells, especially in cases where embryogenic cells are used. Embryonic cell lines are the most potent in organ and tissue grafting, but their use is limited because only few studies have been done in this area (Shimizu et al. 2308).
Despite the potentials associated with the tissue engineering approach, the application is limited, which makes it unpopular in most clinical settings. The cost and technology needed are limitative, which leaves the technological as a method and practice of research rather than for application in clinical settings.
In this context, it would be better to use other techniques such as allografting because they are easy to use and less costly. Nevertheless, such methods are only used as a temporary dressing to protect the wound and initiate the healing process as the stem cells and keratinocytes are under development.
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