These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Characterization of granulocyte-macrophage colony-stimulating factor receptor on the blast cells of acute myeloblastic leukemia. Author: Onetto-Pothier N, Aumont N, Haman A, Bigras C, Wong GG, Clark SC, De Léan A, Hoang T. Journal: Blood; 1990 Jan 01; 75(1):59-66. PubMed ID: 2153034. Abstract: Iodinated granulocyte-macrophage colony-stimulating factor (GM-CSF) was used to document the specific binding of GM-CSF to all acute myeloblastic leukemia (AML) samples examined in the present study. There was some heterogeneity in the number of GM-CSF binding sites per cell. To determine whether the low level of binding to some patient samples may be attributed to receptor occupancy by an endogenous source of GM-CSF, we devised an acid wash procedure that could remove surface-bound GM-CSF without affecting receptor properties. We thus document that GM-CSF specific binding to AML blasts before or after acid wash was the same, indicating that the observed heterogeneity in binding is not the result of receptor occupancy by an endogeneous source of GM-CSF. Saturation analyses are in favor of the presence of two classes of binding sites on AML blasts: a high-affinity receptor that binds GM-CSF with a dissociation constant (kd) of 3 to 73 pmol/L and a second class of low-affinity receptor that binds GM-CSF with a kd of 1 to 10 nmol/L. Binding studies with two established cell lines KG-1, and IRCM-8 also showed the presence of two classes of binding sites with high and low affinities. Analysis of GM-CSF titration curves in culture indicate that the median effective concentration required for stimulation of blast colony formation (EC50 = 5-36 pmol/L) were in the range of the kd of the high-affinity binding site, suggesting that this high-affinity binding site mediates the proliferative response.[Abstract] [Full Text] [Related] [New Search]