Abnormal expansion of azurophilic granular lymphocytes was observed in a case of 54-year-old man with non-Hodgkin lymphoma. The expanded cells had receptors for sheep erythrocytes but no Fcγ receptors. By phenotypical analysis using monoclonal antibodies, they were positive for Leu-1, -3, -4, -7, but negative for Leu-11. Cytochemical analysis revealed positivity for acid phosphatase and β-glucuronidase. The surface phenotype was obviously different from that of lymphoma cells (B1+). Furthermore, anti-HTLV-I antibody was negative. By functional analysis, these expanded cells had target binding capacity but no target lytic activity against K562 cells. They also had no proliferative response to IL-2.
