Epidermal Langerhans ' cells in Behet ' s disease

Langerhans' cells were studied in the epidermis of two patients with active Beh,et' s disease and compared with those in two normal controls. Ultrastructural morphology and the percentage of Langerhans' cells found were similar in patients' (1.88%o) and the control epidermis (1.79%). The density of Langerhans' cells in adjacent sites of the same epidermis was not homogeneous, being in the range of 0-8-2-8% in Behget's disease and 0-6-4% in the controls. In the controls, Langerhans' cells were distributed unevenly. Some were located near the basal layer of the epidermis while the rest were in the mid and upper layers. In Behcet' s disease most Langerhans' cells were in the mid-epidermis, but some were imniediately beneath the stratum granulosum. In the Behcet's disease epidermis the area occupied by Langerhans' cells was increased by about 25% and the number of granules found increased by about 44%. It is suggested that in Beh,et's disease the Langerhans' cells are in a more active state.