This Gordon Research Conference was established in 1989 to provide an interdisciplinary scientific forum focusing on the development, structure, and function of the barrier of mammalian skin. In humans, the primary barrier of the epidermis resides in a thin (approximately 20 micron thick) highly organized biopolymer called the stratum corneum. This structure forms the terminal differentiation product of the epidermis and serves a number of vital functions including the limitation of water loss and protecting the body from infection and environmental toxins. The primary focus on the stratum corneum serves to distinguish this meeting from the complementary GRC on "Epithelial Differentiation and Keratinization" which focuses primarily on the cell biology of the epidermis.

The physicochemical organization of the stratum corneum and the role of this structure as a barrier in mammalian skin are becoming increasingly important to understand. Life threatening illnesses such as AIDS and anthrax have their initial portal of entry as breaks in epithelial surfaces. Occupational hand dermatitis and skin sensitization in the workplace are major causes of employee absenteeism. The delivery of drugs and genes across the skin surface has been thwarted by our inadequate understanding of the physical chemical properties and biological organization of the epidermal barrier. The exciting possibility of transcutaneous vaccination targeting intraepidermal Langerhans cells requires delivery of vaccines across the epidermal barrier. Noninvasive monitoring of the skin surface (electrical, chemical, optical) necessitates coupling of sensor systems to the stratum corneum.

All these areas of scientific endeavor require focus on the surprisingly complex organization of the human stratum corneum. The present conference offers a unique meeting place for investigators from academia, industry, and government to discuss problems and opportunities related to the barrier of mammalian skin. This conference attracts experts in the basic biology of barrier lipid synthesis and cornified envelope development as well as engineers and physical chemists focused on physicochemical methods of stratum corneum analysis and drug delivery. To our knowledge, there is no other similar forum which combines such a broad and important site for interdisciplinary discussion of this increasingly important and practical scientific topic.