In vitro radiosensitivity of the spontaneous cytotoxicity of blood lymphocytes in patients with untreated Hodgkin's disease.

The in vitro X-ray sensitivity of the natural killer (NK) cell activity and interferon (IFN)-inducible NK activity of blood lymphocytes obtained from 12 patients with untreated Hodgkin's disease (HD) and 12 healthy subjects was compared. It was observed that the NK activity against K562-cells decreased in a roughly linear fashion within the dose range of 4.0-16.0 Gy and there was no demonstrable difference between patients and controls. IFN treatment of the irradiated cells increased their NK activity to a higher relative extent than in unirradiated cells. On a relative basis, this increase became more pronounced as the X-ray dose was increased. The extent by which IFN could augment NK activity of lymphocytes, whether irradiated or not, did not differ between patients and controls. It is concluded that the radiosensitivity of NK activity and IFN-inducible NK activity of blood lymphocytes in HD is similar to that of healthy individuals, which is in contrast to T-cells and T-cell responses in this disease.