Proportion of memory T cells.

The percentage of memory cells, defined by high expression of CD29, among CD4⁺ (A) and CD8⁺ (B) T cells in uninfected (white bars) and SIV-infected macaques with (dark gray bars) or without (light gray bars) signs of AIDS was determined by flow cytometry. *Significantly different compared with uninfected monkeys (P ≤ .05).