Regulation of normal myelopoiesis and chronic myelogenous leukaemia cell proliferation through a non-cytotoxic mechanism by a gamma/delta T cell clone.
Regulatory effects on myelopoiesis and myelogenous leukaemia cell proliferation mediated by a human T cell clone (TCC) carrying a gamma/delta receptor have been studied. MHC-unrestricted cytotoxicity could be induced in this clone by culture with IL-2 but not IL-4. Increasing concentrations of IL-2 resulted in increased lysis of natural killer (NK)-susceptible target cells but lysis of NK-resistant targets could not be induced. Moreover, cytotoxicity on fresh chronic myeloid leukaemia cells was not measurable even after culture with 1000 U/ml IL-2. However, NK-resistant targets could be lysed when anti-receptor antibodies (OKT3 or TCR-delta 1) were added to the assay. Clone 290-2 cells secreted lymphokines potentially inhibitory for myelopoiesis (TNF-alpha, IFN-gamma), and their supernatants could inhibit optimally stimulated granulocyte/macrophage colony formation by normal bone marrow. Moreover, 290-2 cells prevented the consistently observed IL-3-stimulated enhancement of proliferation of CML cells, although even IL-3-pretreated leukaemic cells were still resistant to lysis by this clone. Thus, cells of this type, even when not directly cytolytic, could have a role in the regulation of myeloid cell growth.
Pawelec
G
G
Immunology Laboratory, Medical Clinic, University of Tübingen, F.R.G.
Sayers
T
T
Busch
F W
FW
D000911:Antibodies, Monoclonal; D002455:Cell Division; D002478:Cells, Cultured; D002999:Clone Cells; D003601:Cytotoxicity Tests, Immunologic; D006410:Hematopoiesis / Q000502:physiology*; D006801:Humans; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000276:immunology*; D008222:Lymphokines / Q000378:metabolism / Q000494:pharmacology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D013997:Time Factors
D000911:Antibodies, Monoclonal; D008222:Lymphokines; D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta