Cellular and substrate adhesion molecules (integrins) and their ligands in cerebral amyloid plaques in Alzheimer's disease.

Integrins belonging to different subfamilies can be identified immunohistochemically in cerebral amyloid plaques. Monoclonal antibodies against the VLA family beta 1-integrins show staining of the corona of classical amyloid plaques for beta 1, alpha 3 and alpha 6. Immunostaining reveal also the presence of collagen and laminin in the corona. Activated microglial cells in classical plaques strongly express receptors belonging to the LeuCAM family (beta 2 integrins). The ligands ICAM and activated complement C3 are found in both amorphous and classical plaques. Vitronectin receptor (alpha v) is found in glial cells in classical plaques but its ligand vitronectin is seen in both amorphous and classical plaques. The data presented here demonstrate the presence of different cellular and substrate adhesive molecules (integrins) and their ligands in classical plaques. The findings suggest that amyloid plaques show signs of regeneration and tissue remodelling.