PROGRAMMED CELL-DEATH IN BRAINS OF HIV-1-POSITIVE AIDS AND PRE-AIDS PATIENTS

Neuropathological studies have revealed that the brains of HIV-1-infec ted AIDS patients show the typical encephalitis and, in addition, neur onal loss. More secently, this neuronal cell loss has been thought to take place via programmed cell death (apoptosis) which has been demons trated by an in situ end labelling (ISEL) technique. In this study 54 brains of HIV-1-positive patients were investigated by the ISEL techni que to investigate whether apoptosis is also present in the brains of patients at the asymptomatic stage. Of these, 10 patients suffered fro m HIV encephalitis (HIVE), 8 had AIDS without neuropathological disord ers and 36 were HTV-1-positive pre-AIDS patients. Apoptotic cells were detected in 6 of the 10 HIVE, 1 of the 8 AIDS without central nervous system (CNS) disease and 4 of the 36 asymptomatic individuals. A diff erence seen between the AIDS and pre-AIDS cases was that, in the latte r, apoptotic cells were found in the white matter in all 4 cases, whil e only 2 of these 4 showed apoptotic neurons. The presence of apoptoti c cells in a number, albeit small, of brains of HIV-1-positive pre-AID S individuals, combined with abnormalities described previously in the same group of patients gives further support to the opinion that brai n damage already occurs during the early stages of HIV infection.