Binding and suppressive activity of human recombinant ferritins on erythroid cells.
We studied the relation between ferritin cellular binding and suppressive activity of recombinant H- and L-ferritin on human erythroid cells at different proliferation/differentiation phases. L-ferritin failed to show any suppressive activity or detectable binding to erythroblasts at any stage of maturation. In contrast, H-ferritin demonstrated binding to erythroblasts derived from peripheral BFU-E cells which increased steadily between 7-14 days of culture up to 15,000 molecules per cell. Reticulocytes and erythrocytes failed to bind either L- or H-ferritin. H-ferritin suppressed BFU-E colony formation and reduced K562 cell proliferation at nanomolar concentrations. This suggests that the expression of H-ferritin binding sites is modulated by cellular proliferation and differentiation, that cells expressing H-ferritin binding sites are sensitive to ferritin suppressive activity and that a causal relation exists between ferritin cellular binding and suppressive activity.
Fargion
S
S
Institute of Internal Medicine and Medical Physiopathology, Milan, Italy.
Cappellini
M D
MD
Fracanzani
A L
AL
De Feo
T M
TM
Levi
S
S
Arosio
P
P
Fiorelli
G
G
D001665:Binding Sites; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D004912:Erythrocytes / Q000378:metabolism; D015672:Erythroid Precursor Cells / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D004920:Erythropoiesis / Q000187:drug effects; D005293:Ferritins / Q000378:metabolism / Q000494:pharmacology*; D005312:Fetal Blood / Q000166:cytology; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism / Q000473:pathology; D011485:Protein Binding / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology; D012156:Reticulocytes / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000378:metabolism / Q000473:pathology
D011994:Recombinant Proteins; D005293:Ferritins