Representative cytofluorographic assessment of CD4 and CD8 cells stained with 7-AAD (apoptotic cells). Two-color immunofluorescence staining was performed on CD4 and CD8 lymphocytes to analyze the staining by 7-AAD. Representative results are shown for CD4 and CD8 T cells from a control individual (A) and an HIV-infected person at baseline (B) and after 150 days of L-carnitine treatment (C). The vertical bar represents the threshold above which 7-AAD staining was considered positive.