Sunburn is an accute uv caused damage of the skin, manifested by reddening and in some case blistering. The sunburn is a delayed erythema initially characterised by the appearance of 'sunburn cells', the depletion of antigen-presenting cells (APC), and the infiltration of the epidermis and dermis by a variety of inflammatory cells, e.g. mast cells, monocytes and lymphocytes. Subsequently the skin responds with hyperproliferation. Sensitivity to sunburn varies based on pigmentation, where lightly pigmented individuals are much more sensitive than heavily pigmented ones. Being best known from men, sun burn can be observed also on pigs.