Defective activity of monocytes from patients with non-Hodgkin lymphoma

Abstract

Mononuclear phagocytic function is not well defined in non-Hodgkin lymphoma patients although, defective function of those cells has been reported in patients with Hodgkin disease and other solid tumors. The potential application of granulocyte-macrophage-colony stimulating factor (GM-CSF) in the prevention and treatment of infections in those patients is being studied. Phagocytosis and microbiocidal activity of monocytes in peripheral blood from 10 newly diagnosed patients and 14 healthy donors were tested cytologically against a strain of Candida albicans, and chemotaxis was evaluated in a Boyden chamber using zymosan-activated serum as a chemotactic agent. Cells were assayed under basal conditions and after incubation with GM-CSF (12 ng/mL). The phagocytosis and chemotactic activity of monocytes from non-Hodgkin lymphoma patients was lower than results obtained with cells from healthy donors (P < 0.05), and microbiocidal activity against Candida albicanswas similar in both groups. After exposure to GM-CSF, the functional activity of monocytes from control donors was only slightly modified (P > 0.05); by contrast, the percentage of mononuclear phagocytic cells in non-Hodgkin lymphoma (NHL) patients increased from 41 +/- 3% to 53 +/- 3%, the phagocytic index from 0.6 +/- 0.1 to 0.87 +/- 0.1 (P < 0.05), microbiocidal activity against Candida from 54 +/- 5% to 66 +/- 6% (P > 0.05), and chemotaxis from 43 +/- 8 cells per field to 48 +/- 9 cells per field (P > 0.05). The results of this study indicate that there is defective phagocytic and chemotactic activity in monocytes from NHL patients at diagnosis. "In vitro" improvement of phagocytic activity was observed after exposure to GM-CSF.