The significance of Leu 8 negative T cells in lymphoid skin infiltrates: malignant transformation, selective homing or T-cell activation?

Abstract
The expression of Leu 8 was studied on skin biopsies from a large group of patients with benign and malignant skin disorders and correlated with the expression of T‐cell differentiation antigens and activation markers. The effect of in vitro stimulation of peripheral blood T cells and T‐cell subsets on the expression of Leu 8 antigen was also determined. In all the skin diseases studied an inverse relationship was found between the proportions of cells expressing Leu 8 and HLA‐DR. A deficiency of Leu 8 positive cells was not specific for mycosis fungoides, but was also found in several reactive dermatoses. Stimulation of peripheral blood cells with phytohaemagglutinin (PHA), concanavalin A (Con A), and anti‐CD3‐PMA resulted in a considerable decrease of Leu 8 antigen expression on day 3 in both CD4+ and CD8+ T cells. These data suggest that the low proportion of Leu 8+ T cells in mycosis fungoides and several reactive skin disorders is not related to malignant transformation or selective homing of Leu 8 T cells, but probably results from local T‐cell activation.

This publication has 15 references indexed in Scilit: