Granulocyte-macrophage colony-stimulating factor binding sites and oxidative metabolism in human granulocytes.
We investigated the interaction between GM-CSF and its receptor on human granulocytes and on several human tumor cell lines. Specific high-affinity binding for GM-CSF was characterized by Scatchard plot analysis. The specific radioactivity of the 125I-labeled derivative of rH. GM-CSF was determined by self-displacement analysis and calculated to be 30 microCi/micrograms. The maximum concentration of binding sites (B max) in granulocytes was 40 fmol/mg protein (2,200 molecules GM-CSF bound/cell) and the dissociation constant (KD) was 0.42 nM. No binding sites for GM-CSF were found in two lung cancer cell lines, SCLC-16HV and NCI-N417 or in the urinary bladder carcinoma cell line 5637, whereas the promyelocytic leukemia cell line HL60 was positive for GM-CSF binding. Time course experiments showed maximum binding of GM-CSF in granulocytes after an incubation period of 60 min and a decrease in binding after an incubation period of 2 h. In parallel, we found a maximum biological signal when granulocytes were preincubated for 90 min with GM-CSF, and a decrease after an incubation time of 120 min. Preincubation of the cells with rH. GM-CSF induced an enhancement of the production of activated oxygen species by the cells in response to PMA.
Häder
M
M
Department of Medicine, University of Marburg, Federal Republic of Germany.
Klausmann
M
M
Pflüger
K H
KH
Lüben
G
G
Seiler
F R
FR
Havemann
K
K
D001665:Binding Sites; D002478:Cells, Cultured; D003115:Colony-Stimulating Factors / Q000378:metabolism*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006098:Granulocytes / Q000378:metabolism*; D006133:Growth Substances / Q000378:metabolism*; D006801:Humans; D009504:Neutrophils / Q000378:metabolism; D010084:Oxidation-Reduction; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014407:Tumor Cells, Cultured / Q000378:metabolism
D003115:Colony-Stimulating Factors; D006133:Growth Substances; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013755:Tetradecanoylphorbol Acetate