Endogenous avidin biotin activity (EABA) in thyroid pathology: immunohistochemical study

Abstract

Immunohistochemical methods based on the high affinity of avidin and biotin (e.g. ABC, LSAB) are characterized by high sensitivity and are widely used for detection of immunologic reaction. However, a non-specific reaction, observed in frozen tissues and in paraffin-embedded material, increasing after heat induced epitope retrieval (HIER), and caused either by endogenous biotin or any another chemical compound with high affinity for avidin, may lead to diagnostic mistakes. The aim of our investigation is to study presence of endogenous avidin biotin activity (EABA) in thyrocytes originating from various thyroid pathological lesions (neoplastic and non-neoplastic).