Effects of lethal irradiation and cyclosporin A treatment on the growth and tumoricidal activity of a T cell clone potentially useful in cancer therapy.
The TALL-104 cell line, originally derived from a patient with T cell leukemia, can be maintained indefinitely in culture in the presence of interleukin-2 (IL-2) and is endowed with a highly potent major-histocompatibility-complex (MHC)-non-restricted tumoricidal activity both in vitro and in animal models. The present study analyzes in detail the short- and long-term effects of irradiation and cyclosporin A (CsA) treatment on the growth and tumoricidal function of this T cell clone as compared to polyclonal lymphokine-activated killer (LAK) cell preparations from healthy donors. DNA and RNA syntheses by both TALL-104 and LAK cells were irreversibly arrested a few hours after irradiation with 40 Gy. However, 4-h 51Cr-release assays, performed on different days (day 1 to day 7) after irradiation, showed that the cytotoxic efficiency of TALL-104 cells against hematopoietic and solid tumor targets was only modestly reduced, whereas that of LAK cells was severely inhibited. Moreover, the cytotoxic responses to recombinant human IL-2 and IL-12, measured 18 h after irradiation and cytokine addition, were normal in the case of TALL-104 cells but were abolished in the case of LAK cells. Co-culture of IL-2- or IL-12-preactivated TALL-104 cells with a tumor target for 5 days in the absence of cytokines resulted in a lower efficiency of lysis, as compared to the non-irradiated effectors, especially if the initial stimulus was IL-12. These findings suggest the requirement of multiple cytokine stimulation for optimal expression of tumoricidal activity by lethally irradiated TALL-104 cells. CsA, while abrogating TALL-104 cell proliferation at the low dose of 0.5 microgram/ml, inhibited their cytotoxic function marginally only at high doses (100 micrograms/ml). By contrast, CsA reduced dose-dependently the cytotoxicity of LAK cells starting at very low doses (0.5 microgram/ml). CsA did not impair the ability of TALL-104 and LAK cells to produce interferon (IFN) gamma, tumor necrosis factor (TNF) alpha, and granulocyte/macrophage-colony-stimulatory factor (GM-CSF) in response to IL-2, IL-12, or tumor targets. Irradiation reduced drastically IFN gamma production by LAK, but not TALL-104 cells; release of TNF alpha and GM-CSF by either type of effector was inhibited by 10%-50%, depending on the stimulus. The high resistance and immunosuppressive drugs renders tis immortal T cell clone a potentially safe and effective reagent for new adoptive-transfer approaches to cancer in MHC-incompatible recipients.
Cesano
A
A
Wistar Institute, Philadelphia, PA 19104, USA.
Visonneau
S
S
Cioé
L
L
Clark
S C
SC
Santoli
D
D
D000818:Animals; D002999:Clone Cells; D016572:Cyclosporine / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic; D006801:Humans; D018664:Interleukin-12 / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015979:Killer Cells, Lymphokine-Activated / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology / Q000528:radiation effects*; D008222:Lymphokines / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000528:radiation effects; D014407:Tumor Cells, Cultured
D007376:Interleukin-2; D008222:Lymphokines; D012333:RNA, Messenger; D018664:Interleukin-12; D016572:Cyclosporine