Receptor-purified, Bolton-Hunter radioiodinated, recombinant, human epidermal growth factor: an improved radioligand for receptor studies.
We report an assessment of the applicability of the Bolton-Hunter method to the radioiodination of epidermal growth factor (EGF). Recombinant human EGF (hEGF) could be radioiodinated successfully by this method, whereas murine EGF could not. Bolton-Hunter 125I-labeled hEGF was compared with commercial 125I-labeled hEGF prepared by the chloramine-T radioiodination method. Neither radioligand was sufficiently pure for a detailed characterization of the purportedly heterogeneous pattern of binding of EGF to its receptors. A procedure based on receptor adsorption was thus developed for repurification of the Bolton-Hunter 125I-labeled hEGF. This provided a much purer radioligand suitable for detailed studies of receptor-binding heterogeneity.
Kermode
J C
JC
Department of Pharmacology, University of Vermont College of Medicine, Burlington 05405.
Tritton
T R
TR
D000327:Adsorption; D004815:Epidermal Growth Factor / Q000302:isolation & purification*; D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D007202:Indicators and Reagents; D007457:Iodine Radioisotopes; D007553:Isotope Labeling / Q000379:methods*; D011869:Radioligand Assay; D011994:Recombinant Proteins / Q000302:isolation & purification; D013388:Succinimides; D014407:Tumor Cells, Cultured
D007202:Indicators and Reagents; D007457:Iodine Radioisotopes; D011994:Recombinant Proteins; D013388:Succinimides; D004815:Epidermal Growth Factor; C022581:Bolton-Hunter reagent; D066246:ErbB Receptors