Macrophages kill T9 glioma tumor cells bearing the membrane isoform of macrophage colony stimulating factor through a phagocytosis-dependent pathway.
Rat T9 glioma cells transfected with the gene for the membrane isoform of macrophage-CSF (mM-CSF) but not for the secreted isoform of M-CSF were directly killed by bone marrow-derived macrophages. Macrophage-mediated cytolysis of the mM-CSF-transfected clone was blocked by using chemical inhibitors of phagocytosis such as iodoacetate, 2-deoxyglucose, gadolinium chloride, and cytochalasin B. In contrast, macrophage-mediated killing of mM-CSF-expressing tumor cells was augmented by the microtubule inhibitor, colchicine. Use of nitric oxide and reactive oxygen intermediate inhibitors failed to alter the macrophage-mediated killing of the mM-CSF-transfected tumor cells. Photomicroscopy, using immunohistochemical staining with the anti-Hck Ab to distinguish macrophages from tumor cells, revealed that phagocytosis began within 2 h after addition of the mM-CSF-bearing tumor cells. Photocinematography confirmed that macrophages first phagocytosized and then lysed the internalized mM-CSF transfectant cells. Using annexin V and acridine orange staining techniques, macrophages phagocytosized living mM-CSF-transfected tumor cells.
Jadus
M R
MR
Department of Laboratory Service, Veterans Affairs Medical Center, Long Beach, CA 90822, USA. Jadus.Martin@Long-Beach.VA.GOV
Williams
C C
CC
Avina
M D
MD
Ly
M
M
Kim
S
S
Liu
Y
Y
Narasaki
R
R
Lowell
C A
CA
Wepsic
H T
HT
D000818:Animals; D001854:Bone Marrow Cells / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D005910:Glioma / Q000276:immunology*; D008262:Macrophage Activation; D016173:Macrophage Colony-Stimulating Factor / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D008565:Membrane Proteins / Q000276:immunology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000502:physiology; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured
D008565:Membrane Proteins; D017382:Reactive Oxygen Species; D016173:Macrophage Colony-Stimulating Factor; D019331:NG-Nitroarginine Methyl Ester