Affinity chromatographic separation of gonadotropic hormone agonist and antagonist antibodies. Implications for structure, immunological and biological properties of glycoproteins.
Gonadotropic hormones which have lost peripheral sugar residues in their oligosaccharide chains display antagonistic properties and produce antibodies that fail to recognize the fully glycosylated hormone (agonist form). These polyclonal antibodies were separated by successive affinity chromatography on divinylsulfonyl-Sepharose coupled agonist and antagonist columns. The immunoglobulin G fraction from the agonist affinity columns recognizes both free agonist and antagonist in solution radioimmunoassays and also when these hormone forms are bound to receptors on gonadal cells. However, antagonist-specific antibodies recognize only the free antagonist in solution but not when it is receptor bound, implying that the conformation of the receptor-bound antagonist is different from that of the agonist. Affinity-purified antibodies against the different forms are useful in analyzing immunological and biological properties of the hormones. The studies with these glycosylated hormones serve as a useful model for other glycoproteins of pharmaceutical value.
Sairam
M R
MR
Reproduction Research Laboratory, Clinical Research Institute of Montreal, Quebec, Canada.
Jiang
L G
LG
D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000302:isolation & purification*; D015153:Blotting, Western; D006063:Chorionic Gonadotropin / Q000276:immunology*; D002846:Chromatography, Affinity; D003429:Cross Reactions; D005640:Follicle Stimulating Hormone / Q000031:analogs & derivatives* / Q000276:immunology; D006023:Glycoproteins / Q000737:chemistry* / Q000276:immunology; D006031:Glycosylation; D006801:Humans; D007986:Luteinizing Hormone / Q000031:analogs & derivatives* / Q000276:immunology; D011487:Protein Conformation; D012756:Sheep
D000906:Antibodies; D006063:Chorionic Gonadotropin; D006023:Glycoproteins; C034923:HCG, deglycosylated; C049669:follicle stimulating hormone, deglycosylated; C030405:luteinizing hormone, deglycosylated; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone