Archival formalin-fixed, paraffin-embedded (FFPE) tissue blocks has been adopted as the standard tissue process method. More than one hundred years, hundreds and thousands FFPE tissue blocks stored at pathology are an invaluable resource for clinical and basic research. Antigen retrieval (AR) has created a revolutionary way to recover the antigenicity masked by formalin fixation in these tissue blocks. Since the AR developed in 1991, it has widely been used in pathology and other morphologic sciences as a breakthrough in the field of immunohistochemistry. Furthermore, AR has also been successfully used in a wide variety of molecular techniques including imaging mass spectrometry, and efficient protein, and nuclei acid extraction from FFPE tissues to improve application of FFPE tissue in molecular pathology. This book summarized critical issues of basic principle of AR, emphasizing how to use AR as a gold key to open the door of FFPE tissue treasure and new dimensions of further development of this AR technique based on abundant published data worldwide and authors' experiences over two decades. This book is intended for biomedical scientists, pathologists, technicians, students.

Shan-Rong Shi is the Professor of Clinical Pathology at USC, until retired in 2012. For his valuable contribution of the Antigen Retrieval Technique, on March 31, 2011, at the 62th Annual Meeting of The HCS, USA, he received the George Gomori Award. He is the Editorial Board of 3 journals, and was a member of The HCS Council (2006-2010).