Scanning electromicroscopy of suction blister-roofs from psoriatic lesions and normal skin.

Suction blisters were raised on psoriatic lesions and normal appearing skin. The epidermis was separated at the epidermal-dermal junction. Scanning electronmicroscopy of the dermal side of the blister-roofs from normal looking skin and almost healed psoriatic lesions showed stellate cells probably formed by cytoplasmic extensions ending at desmosomes. In non-treated psoriatic plaques the cells were rounded and lacked the stellate extensions.