LECTINS by Vector Laboratories Inc.

Although “lectin” was originally coined to define agglutinins that could discriminate among types of red blood cells, today the term is used more generally and includes sugar-binding proteins from many sources regardless of their ability to agglutinate cells. 

Most lectins are multimeric, consisting of non-covalently associated subunits. It is this multimeric structure that gives lectins their ability to agglutinate cells or form precipitates with glycoconjugates in a manner similar to antigen-antibody interactions. This unique group of proteins has provided researchers with powerful tools to explore a myriad of biological structures and processes.

Because of the specificity that each lectin has toward a particular carbohydrate structure, even oligosaccharides with identical sugar compositions can be distinguished or separated. The affinity between a lectin and its receptor may vary a great deal due to small changes in the carbohydrate structure of the receptor. These properties enable the researcher to discriminate between structures, isolate a specific glycoconjugate, cell, or virus from a mixture, or study one process among several.

Another property of some lectins is an ability to induce mitosis in cells that are normally not dividing. This property has been exploited extensively in an attempt to understand the process of lymphocyte blastogenesis and the biochemical and structural alterations associated with mitogenesis.  These important applications include lymphokine production and viral coat protein (eg gp120) isolation.  In fact, thousands of articles on lectins have been published examining hundreds of different aspects and uses of lectins.