Human skin equivalent

The nonpharmacologic treatment of diabetic foot ulcers may include off-loading, chemical or surgical debridement of necrotic tissue, wound dressings, hyperbaric oxygen, vascular or orthopedic surgery, and the use of human skin equivalents.30... 

The human skin model assay involves measuring the effects of corrosives on viable cells in a reconstituted human skin equivalent. To be accepted as a valid human skin model, several criteria must be met. The artificial skin must comprise a functional stratum corneum with an underlying layer of viable cells. Furthermore, the barrier function of the stratum corneum, as well as the viability of the epidermis, must be verified with appropriate experimental setups. The chemicals to be tested are applied up to 4 h as a liquid or a wet powder onto the skin model. Afterwards, careful washing has to be performed, followed by investigation of the cell viability [e.g., with a (MTT)] reduction assay). 

Egles C, Shamis Y, Mauney JR et al (2008) Denatured collagen modulates the phenotype of normal and wounded human skin equivalents. J Invest Dermatol 128 1830-1837... 

In human skin equivalents UV irradition with a full solar spectrum led to a linear depletion of vitamin E with increasing amounts of UV light, while vitamin C was only markedly decreased at the highest amount of 16.8 J/cm2.19... 

In addition to cell lines, artificial human skin has been used to test the effects of SM (Petrali et al, 1993). Human skin equivalent (HSE), commercially available as EpiDerm, is a fiiUy differentiated artificial human skin with both a dermis and an epidermis (Monteiro-Riviere et al, 1997). Full thickness models (EipDerm-FT) have been evaluated for their potential use in SM models as well (Hayden etal, 2005 Paromov etal, 2008). The latter model has been successftilly applied for screening of antioxidant molecules in the treatment of SM injury (Paromov et al, 2008). A lack of knowledge regarding the identity of important biochemical... 

Hayden, P.J., Petrali, J.P., Hamilton, T.A., Kubilus, J., Smith, W.J., Kalusner, M. (2005). Development of a full thickness in vitro human skin equivalent (Epiderm-FT) for sulfur mustard research. Proceedings of the Society of Investigative Dermatology, St Louis, MO. 

Human skin equivalents have been developed by several laboratories. One equivalent, Testskin, consists of human keratinocytes seeded onto a collagen base or collagen-glycosaminoglycan matrix containing human fibroblasts. In many respects, the epidermis which develops resembles epidermis in vivo. The tissue culture system survives for several weeks and may be useful in studying skin penetration. Testskin is a commercially produced skin equivalent system marketed by Organogenesis, Inc. (Cambridge, MA) ... 

The presentation here provides an overview of tlie uses of a perfused skin model such as the IPPSF in percutaneous absorption and dermatotoxieokinetie studies. One of its major advantages is that both absorption and toxicity may be assessed in the same preparation. The pharmaeokinetic models developed arc experimentally verifiable. The major limitations are centered on the cost of the preparation and the technical expertise required to successfully conduct the studies. The overall cost is significantly greater than in vitro diffusion cell studies or in vivo rodent experiments, comparable to human skin equivalent and larger mammal (dog, pig, primate) in vivo work and much less expensive than human trials. However, cost alone is not a sufficient criterion. These studies are humane more information may be gathered than is obtainable with either in vitro or in vivo work. Optimal benefit may be achieved if these studies serve as a bridge between in vitro human/animal and in... 

Michel, M., L Heureux, N., Pouliot, R., Xu, W., Auger, F.A., Germain, L. (1999) Characterization of a new tissue-engineered human skin equivalent with hair. In Vitro Cell Dev Biol Anim, 35 (6), 318-326. 

There are several functional aspects of the compounds to be considered in the cosmetic applications. The primary requisite is its biocompatibility with the skin or hair. The compound should be safe and does not elicit any adverse immunological response. As performance of the compound is related to its structure and physiochemical properties, a proper downstream processing is required to purify the compounds with the intact structure and functional properties. Once a compound shows a promising skin/ hair care activities, a cosmetic formulation could be designed and its safety is checked by animal testing or human skin equivalent testing. At times, volunteer studies have also been performed to check the effectiveness and side effects of the cosmetic formulation. Different functional properties of cosmetically important compounds are discussed below. 

HA IGF + EGF Hydrogel GF stability Proliferation and differentiation of epithelial cells in vitro Human skin equivalent Xie et al. (2011)... 

Mertsching, H., Weimer, M., Kersen, S., Bmnner, H., 2008. Human skin equivalent as an alternative to animal testing. GMS Krankenhaushyg. Interdiszip. 3. 

Zhang, Z., Michniak-Kohn, B.B., 2012. Tissue engineered human skin equivalents. Pharmaceutics 4, 26—41. 

Veves A, Falanga V, Armstrong DG, Sabolinski ML. Apligraf Diabetic Foot Ulcer Smdy. Graftskin, a human skin equivalent, is effective in the management of nonin-fected neuropathic diabetic foot ulcers a prospective randomized multicenter clinical trial. Diabetes Care 2001 24 290-5. 

Falanga V, MargoKs D, Alvarez O, et al. Rapid healing of venous ulcers and lack of clinical rejection with an allogeneic cultured human skin equivalent. Arch Dermatol 1998 134 293-300. 

Brem H, Young J, Tomic-Canic M, Isaacs C, Ehrlich HP. Clinical efficacy and mechanism of bUayered living human skin equivalent (HSE) in treatment of diabetic foot ulcers. Surg Technol Int 2003 11 23-31. 

Brisco, D.M. et al. The allogeneic response to cultured human skin equivalent in the hu-PBL-SCID mouse model of skin rejection. Transplantation, 67,1590-1599,1999. 

Falanga, V., Margolis, D.J., Alvarez, O., Auletta, M., Maggiacomo, F., Altman, M., Jensen, J., Sabolinski, M., and Hardin-Young, J., Rapid healing of venous ulcers and lack of clinical rejection with an allogeneic cultured human skin equivalent. Arch. Dermatol, 134,293,1998. 

Altman, M. Jensen, J. Sabolinski, M. Hardin-Yong, J. Rapid Healing of Venous Ulcers and Lack of Clinical Rejection With an Allogeneic Cultured Human Skin Equivalent. ioq 293-300. 

Black, A.T., Hayden, P.J., Casillas, R.P., et al., 2010a. Expression of proliferative and inflammatory markers in a full-thickness human skin equivalent following exposure to the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide. Toxicol. Appl. Pharmacol. 249, 178-187. 

Petrali, J.P., Oglesby, S.B., Hamilton, T.A., et al., 1993. Comparative morphology of sulfur mustard effects in the hairless guinea pig and a human skin equivalent. J. Submicrosc. Cytol. Pathol. 25,113-118. 

J. P. Petrali, S. B. Oglesby, T. A. Hamilton and K. R. Mills, Comparative Morphology of Sulfur Mustard Effects in the Hairless Guinea-Pig and A Human Skin Equivalent,/. Submicrosc. Cytol Pathol, 1993,25,113-118. A. S. Warthin, The ocular lesions produced by dichlorethylsulfide ( Mustard Gas ),/ Lab. Clin. Med., 1918, IV, 786-832. 

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