BINDING PATTERNS OF MISTLETOE LECTIN-I, LECTIN-II AND LECTIN-III TO MICROGLIA AND ALZHEIMER PLAQUE GLYCOPROTEINS IN HUMAN BRAINS

Glycoconjugates of microglial cells and in some cases those glycoconju gates present in the amyloid plaques in Alzheimer's disease in the cer ebral cortex can be stained with a lectin from mistletoe (ML-I) using a labour-intensive and time-consuming indirect immunoperoxidase techni que. In order to simplify the staining method and to test the staining characteristics of the other recently isolated mistletoe lectins (ML II, ML-III), biotinylated MLs I-III were used together with an avidin- alkaline phosphatase-complex for visualisation. Our findings indicate that this new improved technique can also be used for detection of mic roglial cells and is considerably faster than the old method. In addit ion to microglial cells, ML-I labelled plaque glycoproteins possibly i ndicating that glycoconjugates derived from microglia can be detected in plaques. In contrast to ML-I, both ML-II and ML-III did not stain m icroglial cells.