Apoptosis is common in brains of patients with AIDS, and its severity correlates with the severity of regional HIV encephalitis (HIVE). To further distinguish between apoptosis and other cell death mechanisms in HIVE, we looked for the expression of apoptotic-related genes, using immunohistochemistry to identify caspase 1 (interleukin-converting enzyme beta (ICE)) and caspase 3 as well as HIV gp41; in situ end labeling (ISEL) to detect cells with fragmented DNA, and routine histology for neuronal loss, glial reactivity, and HIVE. Paraffin-embedded sections of basal ganglia were selected since this region bears the brunt of gray matter disease in HIVE. Only 17% of controls showed moderate ISEL and none had caspase immunoreactivity or neuronal loss. 71% of AIDS brains had moderate to severe ISEL; 67% displayed caspase immunoreactivity and neuronal loss; and 57% had HIVE. ISEL and caspase-positive cells included neurons, glia and perivascular inflammatory cells. These results show pro-apoptotic gene expression in AIDS versus HIV-negative brains; their presence strengthens the hypothesis that cell death mechanisms in AIDS brains are apoptotic rather than necrotic. They confirm prior studies that show increased ISEL in AIDS brains but, in contrast to our prior study, did not correlate ISEL severity with HIVE.
|Original language||English (US)|
|State||Published - Mar 20 1998|
ASJC Scopus subject areas
- Molecular Biology