Tissue fixation – the most underestimated methodical feature of immunohistochemistry

The present review supplies for the first time a comparative approach referring to negative or positive effects of the most important and approved fixation media used in immunohistochemistry (Formalin, Bouin`s solution), that are discussed related to specific impacts caused by the new HOPE fixation technique. Moreover, possible other influences on the effectiveness of the fixatives (specimen collection and post-harvesting delay, chemical characteristics of fixatives, fixation temperature and duration, tissue and organ structure, localization problems of reaction products, approved fixation media versus HOPE fixation) are summarised that may have any remarkable consequences for the structural quality and the immunoreactivities of the different tissues or organs studied. Additionally, information from recent immunohistochemical findings of the authors was introduced to include personal practical experience of many years.