FIG 4.

CD8⁺ T cells recovering after depletion are mostly activated effector memory cells. CD8⁺ T-cell subpopulations and activation levels (CD38 and HLA-DR expression) in blood were monitored by flow cytometry. Naive, CM, and EM cells were distinguished on the basis of CD28 and CD95 expression levels. (A) Follow-up of absolute counts of naive, CM/TM, and EM CD8⁺ T cells in blood at various time points. (B) Expression of the activation markers CD38 (top), HLA-DR (middle), or both (bottom) by EM CD8⁺ T cells. Note that 13311 did not show any reconstitution of CD8⁺ cells before death and 13316 exhibited extremely late partial reconstitution of CD8⁺ cells; this precluded any phenotypic analysis of CD8⁺ T cells in 50 μl of whole blood for these 2 animals during this period.