Microenvironment of Woringer-Kolopp's disease.

A localized form of 'Pagetoid reticulosis' (Woringer-Kolopp's disease) is described morphologically. It can be shown that ultrastructurally the 'Pagetoid cells' are heterogenic and that different cell types can be distinguished: there are lymphoid cells, which often look like Lutzner cells, and nonlymphoid cells which can be characterized as indeterminate cells or Langerhans' cells. Often a close topographical relation between lymphoid and nonlymphoid cells can be demonstrated. This finding is suggestive for a functional interaction between the lymphoid cells, which are most probably T cells, and indeterminate cells and Langerhans' cells, which are known to be important for the thymus-dependent immune reaction. The presence of the nonlymphoid cell population in the epidermis in Woringer-Kolopp's disease seems to build up the specific microenvironment for lymphoid cell reaction.