INCREASED EXPRESSION OF HEAT-SHOCK PROTEIN 27 KDA IN ALZHEIMER-DISEASE - A PRELIMINARY-STUDY

STRESS-response (heat shock) proteins (hsps) are induced in living cel ls under pathological conditions, including diseases of the central ne rvous system. Increased synthesis of hsps is suggested to play a role in preventing neuronal injury in Alzheimer disease (AD). Using a highl y specific antibody we have studied the expression of heat shock prote in 27 kDa (hsp 27), in the brains of AD and nondemented, age-matched c ontrol patients. Immunoblotting and immunohistochemical methods were u sed. We report here that in the human brain in the normal condition th e expression of hsp 27 is low and limited to the vessels, subpial astr ocytes and single astrocytes of the white matter. There is a significa nt increase in the expression of hsp 27 in the cortex of AD. In AD, th e immunoreaction is mainly localized in proliferating astrocytes estab lishing a pattern of astrocytic gliosis. These findings are the first to show the presence of hsp 27 in human cerebral tissue in normal cond itions and its induction in AD.