Immunohistochemistry definition

This section summarizes the current information about different human keratins, their functional significance, cell-type-specific distribution as well as their coexpression with myoepithelial markers and estrogen receptor alpha (ER), because these markers exhibit characteristic expression patterns in some human breast tumors. In many of these cases, a definite diagnosis can be achieved only when additional information is provided by immunohistochemistry. 

Immunohistochemistry also shows that a protein which cross reacts with antibody raised against the cotyledon 62 kD protein exists in leaves. The cross reacting protein is localized primarily in three cell types of the phloem of mature leaves. Studies at the electron microscope level further show that the intra-cellular localization is again exclusively in the outer membrane of the cells. While these unpublished results do not prove that the 62 kD cotyledon protein is a sucrose carrier, they are very encouraging and may prove very useful in studying the developmental regulation of this transport process as well as providing the further tools needed to definitively identify the carrier protein. 

Up to now attempts to provide a selective morphological detection of glucagon in the A cells of pancreatic islets have been carried out by means of im-munohistochemicaI techniques or indole methods. By immunohistochemistry the presence of glucagon in the cytoplasm of some islet cells has been definitively ascertained, but the exact nature of these cells has not been completely established (Baum et al., 1962 Chiappino et al., 1963). In fact, the most reliable and selective methods for islet cytology are not appliable to fresh cryostatic sections which are required by im-munoh i stochemi caI techniques. 

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