Vegetable lectins are particularly suitable for the stimulation of lymphocytes under in vitro conditions. An important mitogen group is the lectins, sugar-binding proteins. Lectins specifically bind to membrane-glycoproteins of different cells, including lymphocytes. They effect thereby agglutinations producing cell activation and proliferation.
Vegetable agglutinins (mostly legumes) can party agglutinate erythrocytes according to the species and blood groups (therefore named phytohemagglutinins or lectins). This includes also Concanavalin A (Con A), a protein extracted from Canavalia ensiformis, which was found to effectively agglutinate human erythrocytes.
Phytohemagglutinins (PHA) that mainly agglutinate erythrocytes are referred to as E, whereas PHA with lymphocytes stimulating properties as PHA L.
A routine test of mitogen stimulation and nomenclature