Figure 1.

FADD deficiency impairs early thymocyte development only in Lck-FADD mice. (a) Thymus from a Lck-FADD mice (up, 7 weeks) and CD4-FADD mice (low, 5 weeks) with their littermate controls. Horizontal bar stands for 2 mm. (b) Thymic cellularity of Lck-FADD and CD4-FADD mice. Histograms depict the thymus total cellularity. S.D. calculated from five mice. ***P<0.001. (c and e) Representative flow cytometric analysis of thymus of Lck-FADD (up) and CD4-FADD mice (low) and their littermate control. Thymocytes were stained by using Abs to CD4 and CD8 or TCRγδ (n>3). The percentage for each quadrant is displayed in the appropriate quadrant. Each plot represents at least 10 000 events. Histograms showing absolute numbers of thymic populations in the different Tg mice or littermate controls. **P<0.01. (d) DN thymocytes stained with anti-CD44 and anti-CD25 to identify DN1–DN4 thymocytes from Lck-FADD (up) and CD4-FADD mice (low) with their littermate control (n>3). Absolute numbers of total DN3 and DN4 cells from five Tg mice and four littermate controls were calculated, as in Figure 1c above