The influence of ultraviolet radiation on allergic contact dermatitis in the guinea-pig. I. UVB radiation.

Guniea-pigs were sensitized by percutaneous application of dinitrochlorobenzene and exposed to UVB (280-320 nm) radiation. The exposure to radiation diminished the response to an elicitation dose of the hapten administered 14 days later within the site of irradiation. The exposure dose of radiation required to produce this effect resulted in a marked erythemal response, but this response did not conceal the contact allergic reaction. The site of elicitation of the allergic response had to be included in the exposure field.