Abnormal Proliferation of Large Granular Lymphocytes with Natural Killer Activity and Peculiar Phenotype (HNK-1⁺, OKT3⁺, 4⁺, 8⁺ and IgG EA^-)

Abstract

A 81-year-old female with abnormal proliferation of large granular lymphocytes (LGL) showing peculiar properties is presented. The expanded LGL had receptors for sheep erythrocytes but no Fcγ receptors. By phenotypical analysis using monoclonal antibodies, they were positive for OKT 3, 4 and 8 but negative for OKT 6, 10. HNK-1 antigen could be identified on almost all expand cells. However, OKM1 antigen could not be detected. By functional analysis of these expanded cells, they showed natural killer (NK) activities and could proliferate exponentially by the 4th week after the begining of culture with the addition of IL-2. These functions are though to be consistent with those of LGL. Nevertheless, they could also respond to T-cell mitogen, PHA and concanavalin A. The relationship between abnormal proliferation of LGL and chronic T-cell proliferative disorders is discussed in this paper.