The clinical expression of allergy in the skin.

The cutaneous immune system has evolved to protect the organism from potential exogenous pathogens in a complex manner. Recent investigations of the special role of the skin in allergy have focused on the proinflammatory potential of various cells such as Langerhans' cells, keratinocytes, mast cells (MC), endothelial cells, and dermal fibroblasts. Furthermore, in processing and reacting to antigens, infiltrating inflammatory cells (lymphocytes; monocytes; macrophages; and eosinophil, neutrophil, and basophil granulocytes) play an important role both by cell-cell interactions with specific receptors on cell surfaces and via soluble mediators.