Whole blood assay for NK activity in splenectomized and non-splenectomized hairy cell leukemia patients during IFN-alpha-2b treatment.
Natural killer cell (NK) activity in peripheral blood (PB) was followed longitudinally for up to 2 yr after initiation of low-dose IFN-alpha-2b therapy in nine hairy cell leukemia (HCL) patients. A whole blood NK (WB-NK) assay was employed in order to measure the NK activity per unit blood. The pretreatment WB-NK activity was consistently low, indicating that the patients' total NK activity in PB is decreased. Striking differences in WB-NK activity were observed between splenectomized and non-splenectomized patients, whereas no consistent patterns were found when using the conventional NK assay. Thus the WB-NK activity of splenectomized patients showed an immediate increase after initiation of treatment, while the activity in non-splenectomized patients decreased and remained low during the first 3-6 months. Subsequently, after reduction in spleen size, the WB-NK activity began to increase. In splenectomized patients, a second rise in WB-NK was observed after 3-6 months of therapy, coinciding with the normalisation of the peripheral blood counts. In both groups of patients incubation with IFN in vitro induced a rise in NK activity before start of treatment, which was abrogated promptly after initiation of therapy, indicating a maximal in vivo boosting of the NK cells. These differences observed indicate that the response of splenectomized and non-splenectomized HCL patients to IFN treatment should be evaluated separately.
University Department of Medicine and Haematology, Aarhus Amtssygehus, Denmark.
B
B
Nielsen
P
P
Hokland
J
J
Ellegaard
H
H
Hasselbalch
M
M
Hokland
D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D007113:Immunity, Innate; D007370:Interferon Type I / Q000627:therapeutic use*; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use*; D007694:Killer Cells, Natural / Q000276:immunology*; D007943:Leukemia, Hairy Cell / Q000276:immunology* / Q000628:therapy; D008297:Male; D011994:Recombinant Proteins; D013156:Splenectomy; D013997:Time Factors
D007370:Interferon Type I; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins