From:  Heterophile antibody interference in cardiac biomarker testing: mechanisms, pitfalls, and clinical consequences

 Mechanisms of heterophile antibody-mediated immunoassay interference.

MechanismUnderlying analytical interactionAssay type most affectedResult patternClinical risk
Antibody bridgingCross-linking of capture and detection antibodies independent of the analyteSandwich immunoassaysFalse-positive elevationOvertreatment
Blocking of analyte bindingSteric hindrance prevents analyte-antibody interactionSandwich immunoassaysFalse-negative resultMissed diagnosis
High-affinity nonspecific immune complex formationStable circulating antibody-mediated macrocomplex formationHigh-sensitivity platformsPersistent abnormal valuesChronic mislabeling
Platform-specific reagent interactionInteraction with assay-specific blocking agents or antibody sourcesManufacturer-dependentInter-assay discordanceDiagnostic confusion