Presence of T cells expressing specific TCR-Vβ chains in periphery and thymus, 3 to 4 months after DLI.

The frequency of T CD4⁺ and CD8⁺ T cells, expressing specific TCR Vβ chains was determined by flow cytometry using FITC-labeled anti–Vβ-TCR and anti–CD4-PE and anti–CD8-PerCP monoclonal antibodies. Results are expressed as percentage of T cells, expressing the specific TCR-Vβ chain, among total single-positive CD4⁺ (upper panels) or total single-positive CD8⁺ T cells (lower panels), in spleens (black bars) or thymuses (empty bars) of chimeras, given DLI at week 3 (DLI). Control chimeras (no DLI) had not been challenged with DLI at week 3. Data represent mean ± SE of 10 individual DLI chimeras and 6 individual cochimeras from 3 identically designed experiments. *P < .05 for comparison between spleen values of DLI and no DLI; **P < .05 for comparison between thymus values of DLI and no DLI, as tested by the Mann-Whitney Utest.