Expression of the erythropoietin receptor on a human myeloma cell line.
We demonstrated the expression of the erythropoietin (EPO) receptor by a human myeloma cell line (MM-S1) which was established in our laboratory. EPO dose-dependently stimulated the proliferation of MM-S1 cells. Binding of radioiodinated EPO (125I-Epo) to MM-S1 cells was competitively inhibited by unlabeled EPO, but not by other recombinant cytokines. Specific binding of 125I-Epo to MM-S1 cells was saturable, and the Scatchard analysis revealed 330 EPO binding sites per cell with a Kd of 0.56 nmol/L. Bound EPO was internalized by MM-S1 cells during incubation at 37 degrees C. This is the first report describing the expression of the EPO receptor by human cells other than those of the erythroid lineage.
Okuno
Y
Y
Second Department of Internal Medicine, Faculty of Medicine, Kyoto University, Japan.
Takahashi
T
T
Suzuki
A
A
Ichiba
S
S
Nakamura
K
K
Hitomi
K
K
Sasaki
R
R
Imura
H
H
D002455:Cell Division / Q000187:drug effects; D004921:Erythropoietin / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D009101:Multiple Myeloma / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000096:biosynthesis* / Q000378:metabolism; D017467:Receptors, Erythropoietin; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
D011956:Receptors, Cell Surface; D017467:Receptors, Erythropoietin; D004921:Erythropoietin