MATERIALS AND METHODS

The subjects selected for investigation com-prised three otherwise healthy males with vitiligo, and three normal males as controls. Two of the pa-tients with vitiligo (A and B) were Europeans aged 19 and 54 years respectively, and the third (C) was a Pakastani, aged 27. Typical depig-mented areas were splashed on the chest, flanks, and genitalia of subject A, and widespread num-mular lesions were present on the forearms of subject B. Subject C had lesions on the front of the neck and the extensor surfaces of the forearms. Of the control subjects, two were European, and the third was African.

In the patients with vitiligo, biopsy material was selected from the centre of a lesion and from an adjacent area of pigmented skin. In subject A, skin was removed from the right flank, and in subjects B and C, from the right forearm. Each biopsy site was anesthetized by subcutaneous infiltration with Lignocaine Hydrochloride. A split biopsy specimen of varying size was then obtained by an horizontal shaving of the skin with a large forged scalpel, the skin being split at a level a little be-low the epidermal-dermal junction. In each case, skin so obtained was divided into parts which were placed in different fixatives as follows: 1. 1% Osmium tetroxide buffered at pH 7.4. Fixation for two hours at 0 C was followed by rapid washing in Ethanol, at which stage the piece of skin was subdivided into smaller pieces. These were embedded in Araldite (20). Thin sections, some of which were stained with lead hydroxide dissolved in Methanol, were examined in a Sie-mens ELMISKOP 1 electron microscope. Thicker sections (1 tz) of this material were also examined by phase contrast microscopy. 2. 10% Formalin. From this material sections were obtained which were either stained with haematoxylin and eosin or impregnated with silver nitrate following Masson's (21) technic. 3. Formic acid lemon juice. These specimens were subsequently treated with gold chloride fol-lowing Gairn's technic as described by Becker and Zimmermann (22), and sectioned. 4. Formal calcium chloride. Fixation for one and a half hours was followed by incubation for four to six hours in buffered 1/1000 dopa at 37 C, dehydration, and sectioning. Some of these sections were counterstained with routine stains. In addition to the above, pure epidermal sheets