title: Use of detergent-based buffers allows detection of precursor inhibin forms in an immunoassay format.
abstract: Inhibin ELISAs are used in monitoring aspects of reproductive function, however these assays are based on the measurements of the mature 30kDa inhibin forms and not precursor forms. In conventional ELISA formats, the 105kDa unprocessed 'Pro-inhibin' forms are immunologically inactive, but the immunoactivity can be recovered in the presence of detergents. The immunoactivity of Pro-inhibin forms was assessed in the presence of a range of detergents utilising antibodies to the α-, βA- and βB-subunits of inhibin. In contrast to mature forms, unprocessed inhibin forms showed a 10-40 fold increase in inhibin A and total inhibin immunoactivities under optimised detergent (0.5% SDS/2% Triton X-100) conditions. The suppressed immunoactivity of the Pro-inhibin forms in these immunoassays was attributed to steric hindrance by the respective βA- and α-subunit prodomains. This study details a detergent-based immunoassay that allows detection of previously undetectable precursor inhibin forms.
authors.affiliation: Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia.
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Walton
authors.forename: Karen L
authors.initials: KL
authors.lastname: Chan
authors.forename: Enid
authors.initials: E
authors.lastname: Pruysers
authors.forename: Emily K
authors.initials: EK
authors.lastname: Kelly
authors.forename: Guy
authors.initials: G
authors.lastname: Harris
authors.forename: Craig A
authors.initials: CA
authors.lastname: Harrison
authors.forename: David M
authors.initials: DM
authors.lastname: Robertson
mesh_terms: D002021:Buffers; D002846:Chromatography, Affinity; D003902:Detergents / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D015571:Follicular Fluid / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D007265:Inhibins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D017830:Octoxynol / Q000737:chemistry; D020033:Protein Isoforms / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D011498:Protein Precursors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry
chemical_list: D002021:Buffers; D003902:Detergents; D020033:Protein Isoforms; D011498:Protein Precursors; C422362:inhibin A; C422364:inhibin B; D012967:Sodium Dodecyl Sulfate; D007265:Inhibins; D017830:Octoxynol
keywords: Immunoassay; Inhibin A; Inhibin B; Inhibin ELISA; Prodomain; SDS