OCCURRENCE OF POSITIVE IMMUNOFLUORESCENCE IN THE DERMO-EPIDERMAL JUNCTION OF SUN-EXPOSED SKIN OF NORMAL ADULTS

A bright, continuous, granular deposition of immunoreactants at the de rmo-epidermal junction (DEJ) of lesional skin is highly suggestive of cutaneous lupus erythematosus (LE). A recent study of the direct immun ofluorescence (IF) of sun-exposed skin in normal adults has demonstrat ed findings similar to the bright, continuous granular pattern found i n cutaneous LE. This data suggests that positive IF from sun-exposed c utaneous lupus lesions is nonspecific. Forty-one healthy adults, witho ut a history of dermatoses or photosensitivity, presenting to the derm atology clinic for the excision of skin cancers were studied. Excess n on-lesional tissue, removed from Moh's excision sites (sun-exposed fac e and neck) in order to obtain appropriate cosmetic closure, was exami ned for the deposition of immunoreactants. The specimens were incubate d with fluoresceinated monovalent anti-human immunoglobulin specific f or IgG, IgA, IgM, C3, C1q, and fibrinogen and examined independently b y 2 immunodermatologists without prior knowledge of patient or site. N one of the samples demonstrated immunoreactant deposition consistent w ith cutaneous LE. IF of several specimens (21/41) had a weak(1+ or 2+) , interrupted pattern of fibrinogen at the DEJ, - a common, non-specif ic finding. Weak, interrupted, linear and granular patterns were seen with IgM (10/41), Clq (9/41), IgG (2/41), IgA (2/41), and C3 (1/41). F ibrinogen was the only immunoreactant demonstrating a bright (3+), con tinuous, granular pattern (4/41). This data suggests that sun-exposure alone does not induce the deposition of immunoreactants at the DEJ in a pattern similar to that found in cutaneous LE.