Aim: Especially at work, frequent contact with lowgrade irritants over a long period may provoke skin disease. Such skin diseases are among the most common occupational illnesses. As part of occupational skin protection programs, skin care products are applied to restore skin barrier function after exposure to irritants and subsequent barrier damage. There are numerous in-vivo tests available to monitor skin regeneration but none of these tests provides any information about the biochemical mechanism of skin barrier repair. The aim of the present study was to elucidate the barrier-restoring mechanism of a skin care emulsion by using a 3-dimensional (3-D) skin model. Method: To investigate regenerative effects, a skin care emulsion was applied onto 3-D skin models damaged with sodium lauryl sulphate (SDS). Skin regeneration was determined by monitoring lactate dehydrogenase (LDH) release, inflammation response (IL-1α) and skin lipid content. Results: The skin care formu lation used in this test enhances the skin barrier, and reduces cell lysis and the release of the inflammatory mediator IL-1α after SDS skin barrier damage. The effectiveness of this skin care formulation in the support of three different skin barrier restoring mechanisms was demonstrated. Conclusion: Utilizing the 3-D skin model it is possible to monitor biochemical repair processes of human skin in-vitro. Thus this model is an important instrument for the determination of the effectiveness of skin care products (e.g. those used for occupational health and safety). This is the first time a 3-D skin model has been us ed to examine the biochemical mechanism of skin barrier repair associated with a skin care product.
