Abstract
Cutaneous T cell lymphoma (CTCL) is a malignancy of helper T cells, which originates in, or predominantly involves, the skin. Initially, these neoplastic cells possess an affinity for the epidermis (epidermotropic type). With the progress of the disease, however, loss of this affinity occurs (non-epidermotropic type) resulting in dissemination of neoplastic cells to extracutaneous sites. The aim of this study is to clarify the differences in the phenotypes and functions of infiltrating cells between epidermotropic and non-epidermotropic type of CTCL.
The majority of the infiltrating cells in CTCL showed positive membraneous staining with OKT 3 and OKT 4 monoclonal antibodies. Significant numbers of OKT 8+ cells were present, especially in epidermotropic type of CTCL. A large percent of infiltrating cells also expressed the Ia-like antigens. Moreover, in some patients with epidermotropic type of CTCL, epidermal cells (keratinocytes) reacted with OKIal monoclonal antibody. In functional analyses, infiltrating T cells isolated from the skin lesions of epidermotropic type of CTCL possessed both helper and suppressor functions, which were not different from those of circulating T cells from healthy individuals in quality. However, dysfunction of infiltrating T cells was detected in non-epidermotropic type of CTCL. It is more likely that the difference in the prognoses between epidermotropic and non-epidermotropic type of CTCL could be ascribed to the percentage of OKT 8+ cells and OKIa1-positive cells in dermal infiltrates and to the functional maturity of infiltrating T cells.
