Apoptosis and apoptosis-associated perturbations of peripheral blood lymphocytes during HIV infection: comparison between AIDS patients and asymptomatic long-term non-progressors

This study was designed to compare the degree of lymphocyte apoptosis and F as-Fas ligand (FasL) expression in AIDS patients and long-term non-progress ors (LTNPs) and correlate these parameters with apoptosis-associated pertur bations in lymphocyte function. LTNPs had a lower frequency of apoptotic CD 4(+) and CD8(+) T cells compared with subjects with AIDS. This correlated w ith a lower frequency of cells expressing Fas and FasL. The frequency of se lected lymphocyte populations exhibiting a disrupted mitochondrial transmem brane potential (Delta Psi (m)) and increased superoxide generation was low er in LTNPs than in patients with AIDS; these abnormalities were associated with lower levels of caspase-1 activation in LTNPs. The results indicate a significantly reduced level of apoptosis and apoptosis-associated paramete rs in LTNPs than in patients developing AIDS. Based on these findings, a cr ucial role for mitochondria can be predicted in the process of lymphocyte a poptosis during the evolution of AIDS.