Epitope mapping on intact, heated and reduced molecular variants of human chorionic gonadotrophin.
Monoclonal antibodies (MAbs) raised against purified human chorionic gonadotrophin (hCG) (n = 30) and synthetic peptides derived from hCG (n = 3) were able to recognize by Western blotting several hCG dimers (57-47 and 42 kDa), free beta-subunits (35-32, 26 and 16 kDa) and free alpha-subunit (21 kDa) which coexist in commercially available hCG preparations. According to differences in the immunoreactivity of hCG-related molecular forms observed under native or denaturing conditions such as boiling or reducing hCG samples before or after gel electrophoresis, nine classes of MAbs able to recognize different immunoreactive domains were determined. Three domains corresponded to continuous epitopes recognized by MAbs raised against hCG-related peptides. The six remaining domains, recognized by the other MAbs, contained discontinuous epitopes from which three were surface-oriented and three disguised in the holo-hormone. This solid-phase approach, combining native and denaturing conditions, represents a simple and powerful tool to screen the specificity of MAbs from varying sources and to investigate molecular variants of proteic hormone.
Research Laboratory on Reproduction (CP-626), Faculty of Medicine, Free University of Brussels (ULB), Belgium.
A M
AM
Nagy
A M
AM
Vanbellinghen
C
C
Robyn
S
S
Meuris
D000911:Antibodies, Monoclonal / Q000276:immunology; D006063:Chorionic Gonadotropin / Q000276:immunology*; D018604:Epitope Mapping; D000939:Epitopes / Q000276:immunology*; D006801:Humans; D010455:Peptides / Q000737:chemistry / Q000276:immunology
D000911:Antibodies, Monoclonal; D006063:Chorionic Gonadotropin; D000939:Epitopes; D010455:Peptides