Binding of different dimeric forms of PDGF to human fibroblasts: evidence for two separate receptor types.
The binding of the three dimeric forms of platelet-derived growth factor (PDGF), PDGF-AA, PDGF-AB and PDGF-BB, to human fibroblasts was studied. Cross-competition experiments revealed the existence of two different PDGF receptor classes: the type A PDGF receptor bound all three dimeric forms of PDGF, whereas the type B PDGF receptor bound PDGF-BB with high affinity and PDGF-AB with lower affinity, but not PDGF-AA. The sizes of the two receptors were estimated with affinity labeling techniques; the A type receptor appeared as a major component of 125 kd and a minor of 160 kd, and the B type receptor as two components of 160 and 175 kd. A previously established PDGF receptor monoclonal antibody, PDGFR-B2, was shown to react with the B type receptor only. The different abilities of the three dimeric forms of PDGF to stimulate incorporation of [3H]TdR into human fibroblasts indicated that the major mitogenic effect of PDGF is mediated via the B type receptor.
Heldin
C H
CH
Ludwig Institute for Cancer Research, Uppsala, Sweden.
Bäckström
G
G
Ostman
A
A
Hammacher
A
A
Rönnstrand
L
L
Rubin
K
K
Nistér
M
M
Westermark
B
B
D000911:Antibodies, Monoclonal; D001667:Binding, Competitive; D002478:Cells, Cultured; D003432:Cross-Linking Reagents; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D008934:Mitogens; D010982:Platelet-Derived Growth Factor / Q000276:immunology / Q000378:metabolism* / Q000494:pharmacology; D011487:Protein Conformation; D011956:Receptors, Cell Surface / Q000378:metabolism*; D017479:Receptors, Platelet-Derived Growth Factor
D000911:Antibodies, Monoclonal; D003432:Cross-Linking Reagents; D008934:Mitogens; D010982:Platelet-Derived Growth Factor; D011956:Receptors, Cell Surface; D017479:Receptors, Platelet-Derived Growth Factor