Deficient interleukin-2-activated killer cell cytotoxicity in patients with systemic lupus erythematosus.

This study was undertaken to determine if the cytotoxic activity of interleukin-2 (IL-2)-activated killer (LAK) cells, which is induced by the direct activation of lymphocytes by IL-2, is defective in systemic lupus erythematosus (SLE). The killer cell activity of SLE patients, whether it be generated in autologous plasma or serum-free media, was significantly less than the controls against three different target cells. It was observed, by incubating control lymphocytes in 10% fresh SLE plasma, that soluble factors were responsible for a portion of the reduced generation of LAK cell cytotoxicity (P less than 0.

Phytohemagglutinin induced proliferation by aged lymphocytes: reduced expression of high affinity interleukin-2 receptors and interleukin-2 secretion.

Human lymphocytes from elderly and young donors were cultured with phytohemagglutinin. Cultures from two groups of aged donors, recruited respectively from our ambulatory clinic and a nursing home, incorporated less tritiated thymidine (3H-TdR) and secreted less interleukin-2 than did young donors. Furthermore, as determined for the first time by a radioligand binding receptor assay, the aged lymphoblasts possessed significantly fewer high affinity IL-2 receptors per cell.

Lysis of human T cell leukemia virus infected T and B lymphoid cells by interleukin 2-activated killer cells.

The human T cell leukemia (HTLV-1) retrovirus is the etiologic agent for adult T cell leukemia. Interleukin 2 (IL-2) activated killer (AK) cells have been shown to lyse freshly explanted tumor cells in vitro and have been used as a form of adoptive immunotherapy for the treatment of cancer. In this report, the ability of AK cells to lyse HTLV-1-infected targets was examined.

Natural killer cells do not lyse resting or mitogen-stimulated B cells.

It has recently been reported that isolated resting natural killer cells lyse autologous resting and mitogen-stimulated B cells. In this report, we have been unable to corroborate these observations and provide indirect evidence that lytic susceptibility is attributable to exposure of the target cells to xenogeneic antigens present in fetal calf serum (FCS). Moreover, we show that interleukin-2-activated killer cells potently lyse normal peripheral blood mononuclear cells which are exposed to FCS.

Induction of lymphokine activated killer cells in serum-free medium.

Lymphokine activated killer (LAK) cells may play a role in immunosurveillance against spontaneous neoplasms. To date, LAK cells have been grown in medium supplemented with human serum (HS). Formulation of a defined medium that supports LAK cell generation would be useful to delineate the mechanisms that regulate LAK cell induction.