Characterisation and application of antibodies specific for the long platelet-derived growth factor A and B chains.
The platelet-derived growth factor (PDGF) family comprises important mitogens for mesenchymal cells. The active dimeric form of PDGF consists of four structurally related A, B, C, and D chains. All PDGF-variants bind to PDGF-receptors. The A and B chains occur with and without basic C-terminal amino acid extensions as long (A(L) and B(L)) and short (A(S) and B(S)) isoforms. PDGF-A and -B form homo- or heterodimers. The biological relevance of short and long isoforms is unknown, although it may relate to different affinities for glycosaminoglycans of the cell glycocalix and intercellular matrix. Commercially available anti-PDGF-A and anti-PDGF-B antibodies cannot discriminate between the short and the long isoforms. Thus, to investigate the function of the long and short isoforms, we raised antibodies specific for the long A and B chain isoforms. The antibodies were affinity-purified and their properties analysed by surface plasmon resonance. Inhibition studies with different PDGF homodimers and dot-blot studies proved their high specificity for the respective isoforms. Both antibodies recognised the target PDGF homodimers complexed to the glycocalix of human arterial smooth muscle cells and human monocyte-derived macrophages. By using these specific antibodies, we were able to confirm at the protein level the synthesis of PDGF-A and -B during differentiation of human monocyte-derived macrophages and to demonstrate the presence of the PDGF-A(L) and PDGF-B(L) isoforms in human arterial tissue.
Wallenberg Laboratory for Cardiovascular Research, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
Gunnel
G
Ostergren-Lundén
Raquel G
RG
Olivas
Pierre
P
Eftekhari
Alexandra
A
Krettek
Xavier
X
Sanjuan
Gunnar
G
Fager
Senén
S
Vilaró
Florentyna
F
Lustig
Johan
J
Hoebeke
D000818:Animals; D000906:Antibodies / Q000276:immunology; D002339:Carotid Arteries / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology*; D002478:Cells, Cultured; D019276:Glycocalyx / Q000378:metabolism; D006801:Humans; D009000:Monocytes / Q000166:cytology / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism*; D010982:Platelet-Derived Growth Factor / Q000276:immunology / Q000378:metabolism*; D011485:Protein Binding; D020033:Protein Isoforms / Q000276:immunology / Q000378:metabolism; D011817:Rabbits; D017479:Receptors, Platelet-Derived Growth Factor / Q000378:metabolism; D020349:Surface Plasmon Resonance
D000906:Antibodies; D010982:Platelet-Derived Growth Factor; D020033:Protein Isoforms; C075278:platelet-derived growth factor A; D017479:Receptors, Platelet-Derived Growth Factor