FAS and infection: Infection with either SIV-rtTAΔnef or SIVΔnef induced α4+β7+ CD4+CD95+ and CD8+CD95+ TCM and TEM subsets although the change in CD4+ TEM cells failed to reach statistical significance the result was skewed by macaque E67, which also was an exception in the CD8+ TEM population (Figure 5).