Combined Lectin- and Immuno-histochemistry (CLIH) for Fluorescence Microscopy.

The function of glycoproteins depends both on their polypeptide chain and sugar residues. For detection and localization of glycoproteins in tissue sections, methods of immunohistochemistry (IHC) and lectin histochemistry (LHC) are usually used separately. For a better understanding of the expression and distribution of variants of glycoproteins, tissue sections can be analyzed by combined lectin- and immuno-histochemistry (CLIH). CLIH exploits the advantages of both IHC and LHC and can therefore contribute to research in glycobiology and other fields of cell biology. Since cancer transformation is accompanied by alterations in the glycosylation of some glycoproteins, CLIH could also be exploited for improved classification of cancers. The chapter considers how CLIH could be employed on paraffin sections and semithin cryosections for fluorescence microscopy. Five different protocols of CLIH are described in detail as well as appropriate negative controls.