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PubMed · 2024941

Specificity of two-site immunometric assays.

B Perry·R S Chapman·M G McConway·D Griffin·G H Beastall
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Abstract

The assessment of specificity in two-site immunometric assays is complex. Conventional approaches based on standard substitution with cross-reactant may yield misleading results. An 'in-house' immunoradiometric assay (IRMA) for human growth hormone (hGH) appeared free from cross-reactivity with human placental lactogen (hPL) in a single point standard substitution experiment performed by the United Kingdom External Quality Assessment Scheme (UK EQAS). However, detailed studies based on the substitution of hGH standards with hPL cross-reactant, the addition of hPL cross-reactant to hGH standards and the recovery of added hGH from endogenous cross-reactant (sera from pregnant subjects) revealed gross cross-reactivity of hPL in the hGH assay. We recommend that the validation of assay specificity should require the demonstration of quantitative recovery of a range of analyte concentrations from human sera that contain varying endogenous concentrations of cross-reactant.

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CalibrationCross ReactionsFemaleGrowth HormoneHumansImmunologic TechniquesPlacental LactogenReproducibility of ResultsSensitivity and SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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B Perry, R S Chapman, M G McConway, D Griffin, G H Beastall. 1991. Specificity of two-site immunometric assays.. https://doi.org/10.1177/000456329102800114

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