Abstract
The distributions of fibronectin (FN) were investigated in experimental contact dermatitis of guinea pigs induced by 2,4-dinitrochlorobenzene (DNCB), using an indirect immunofluorescent technique with a specific antisera against guinea pig plasma FN. In primary irritant contact dermatitis induced by 5% DNCB, FN was found in the areas corresponding to the cell membrane and cytoplasm of Malpigian cells from 3 to 24 hours after painting. FN was detected on the degenerative epidermis or crusts from 3 to 6 day-lesions. Regenerative epidermis showed no specific immunofluorescence of FN. Similar distributions of FN in epidermis were observed only in 9 hour-lesions of allergic contact dermatitis to DNCB. In the retest reaction, FN was also distributed in the areas corresponding to the cell membrane and cytoplasm of epidermal cells from 5 to 9 hour-lesions and was seen in the upper half of the epidermis in the 24 hour-lesion. The significance of deposits of epidermal FN associated with regeneration of epidermal cells and exclusion of degenerative tissues is discussed.
