title: Mechanism involved in gallium-67 (Ga-67) uptake by human lymphoid cell lines.
abstract: The gallium-67 (Ga-67) is a radionuclide used for diagnostic imaging. It is known for its ability to accumulate in inflammatory lesions and tumors, especially in lymphomas. The intracellular distribution and the uptake mechanism of Ga-67 remains a subject of discussion. In this work, we studied the mechanism of Ga-67 uptake in 4 human lymphoid cell lines: 38658, Jurkat, DG75 and U715. Our results have pointed out the heterogeneity of Ga-67 uptake among these cell lines. Using flow cytometry analysis, we reported the expression of transferrin-receptor (TfR) in each lymphoid cell line, and found a positive correlation between TfR density and the Ga-67 uptake (r = 0.99) in lymphoid cells. The anti-TfR monoclonal antibody (MoAb) blocked significantly the Ga-67 uptake in all lymphoid cell lines indicating the Ga-67 uptake as a TfR-dependent mechanism. This mechanism has been saturated with different cold gallium concentrations. A total inhibition of Ga-67 uptake was obtained at a 10(-4) M cold gallium concentration. To conclude, we have shown that the Ga-67 uptake is TfR-dependent in lymphoid cells. Thus, the gallium penetrates in lymphoid cells by an active mechanism which can be saturated.
authors.affiliation: Service d'Hématologie Biologique, EA 1625, Hôpital Avicenne, UFR SMBH, Léonard de Vinci, Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Nejmeddine
authors.forename: N
authors.initials: N
authors.lastname: Caillat-Vigneron
authors.forename: F
authors.initials: F
authors.lastname: Escaig
authors.forename: J L
authors.initials: JL
authors.lastname: Moretti
authors.forename: M
authors.initials: M
authors.lastname: Raphael
authors.forename: P
authors.initials: P
authors.lastname: Galle
mesh_terms: D000911:Antibodies, Monoclonal; D001693:Biological Transport, Active; D002051:Burkitt Lymphoma / Q000000981:diagnostic imaging; D005434:Flow Cytometry; D005709:Gallium Isotopes; D006801:Humans; D019169:Jurkat Cells; D008214:Lymphocytes / Q000000981:diagnostic imaging*; D016399:Lymphoma, T-Cell / Q000000981:diagnostic imaging; D011877:Radionuclide Imaging; D011990:Receptors, Transferrin / Q000032:analysis* / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D000911:Antibodies, Monoclonal; D005709:Gallium Isotopes; D011990:Receptors, Transferrin