Induction of IL-2 activity production in human T cell line, KOPT-5

Abstract

A human leukemic cell line, KOPT-5, was established from peripheral blood mononuclear cells of a 13 year-old boy with T cell acute lymphocytic leukemia. KOPT-5 has T cell phenotype of CD 1 (-), CD 2 (+), CD 3 (+), CD 4 (-), CD 5 (+), CD 7 (+), CD 8 (-). IL-2 activity in the culture supernatant of KOPT-5 was examined. KOPT-5 produces no IL-2 activity constitutionally, but produces IL-2 activity when co-cultured with both phytohemagglutinin (PHA) and macrophage-like differentiated human promyelocytic leukemia cell line HL-60. This differentiation of HL-60 have been induced by phorbol 12-myristate 13-acetate (PMA). KOPT-5 produces no IL-2 activity when co-cultured with macrophage-like differentiated HL-60 only, or with both PHA and non-differentiated HL-60, and KOPT-5 produces lower level of IL-2 activity when stimulated with both PHA and PMA, but produces no IL-2 activity when stimulated with both PHA and IL-1. The T cell line, KOPT-5 will provide a useful model for elucidating the mechanism of the accessory function of macrophage in mitogen-induced T cell differentiation.