Superoxide anion (O₂^-) production by peripheral blood monocytes in Hodgkin's disease and malignant lymphoma

Superoxide anion (O₂^-) is the first metabolite of the monocyte oxygen burst pathway, which plays an important role in the monocyte microbicidal function. The capacity of peripheral blood monocytes to produce O₂^- was studied in 63 patients with Hodgkin's disease (31 with active disease and 32 in complete remission), 15 patients with active malignant lymphoma, and 57 normal control subjects. O₂^- release was quantified by evaluating superoxide dismutase-inhibitable reduction of cytochrome c after stimulation of monocytes with phorbol myristate acetate. Results were expressed in nanomols O₂^- per mg protein per hour. O₂^- production was lower than normal in patients with active Hodgkin's disease (163.3 v 214.5, P < .05). It was normal in patients with Hodgkin's disease in complete remission (216.2 v 214.5, P > .05) and high in patients with malignant lymphomas (317.9 v 214.5, P < .01). Within the group with active Hodgkin's disease, patients in relapse after therapy had a lower O₂^- production than those previously untreated (99.8 v 181.8, P < .01). Stage of disease was unrelated to the defect. The presence of B symptoms and a decreased delayed type hypersensitivity to recall skin test antigens were associated with normal O₂^- production. The results obtained suggest that monocyte dysfunction is part of the immune dysregulation associated with active Hodgkin's disease. The O₂^- determination is a relatively easy test to perform and may be useful in identifying the patients with Hodgkin's disease who have an increased risk of opportunistic infections.