Characteristics of radioimmunoassays for the alpha- and beta-subunits of human luteinizing hormone.
The binding characteristics and specificities of the National Hormone and Pituitary Program (NHPP) kits for the radioimmunoassay of the alpha- and beta-subunits of human luteinizing hormone (hLH-alpha and hLH-beta) were studied, as well as the specificities of the anti-hLH and anti-human follicle stimulating hormone (anti-hFSH) antisera distributed by the same organization. The affinity constants of the anti-hLH-alpha and anti-hLH-beta antisera were calculated at 157 +/- 8.4 nM-1 and 109 +/- 7.4 nM-1, respectively. Both antisera were highly specific with regard to the other subunit. However, in the homologous hLH-alpha RIA, native hLH cross-reacted at 21.9%, hFSH at 17.5% and hTSH at 7.9%. The alpha-subunit of the human chorionic gonadotropin, hCG-alpha, was equipotent with the hLH-alpha standard in this assay. In the homologous hLH-beta RIA, hLH showed a cross-reactivity of 14.7% while the cross-reactivities of hCG-beta, hFSH and hTSH were 3.5%, 1.2% and 0.6%, respectively. The anti-hFSH antiserum was highly specific, while the anti-hLH antiserum showed non parallel competition curves. With this knowledge of the specificity of each antiserum, corrections can be properly made for the assays of hLH, hLH-alpha and hLH-beta while the hFSH RIA can be used without correction for the presence of the three other components.
D000918:Antibody Specificity; D003429:Cross Reactions; D005640:Follicle Stimulating Hormone / Q000032:analysis / Q000276:immunology; D015292:Glycoprotein Hormones, alpha Subunit; D006801:Humans; D007986:Luteinizing Hormone / Q000032:analysis* / Q000276:immunology; D010446:Peptide Fragments / Q000032:analysis* / Q000276:immunology; D010908:Pituitary Hormones, Anterior / Q000032:analysis* / Q000276:immunology; D011863:Radioimmunoassay / Q000379:methods*
D015292:Glycoprotein Hormones, alpha Subunit; D010446:Peptide Fragments; D010908:Pituitary Hormones, Anterior; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone