Figure 2. Activation and cytokine production of alloreactive T cells are diminished in the presence of anti-CD154 dAbs.

(A) Representative histograms of CD44 expression on splenic CD4⁺ and CD8⁺ T cells isolated from grafted mice at day 14. (B) Frequencies of CD44^hi cells among CD4⁺ and CD8⁺ T cell populations. Treatment with MR-1, 7E1-G2b or CD154 dAbs results in the reduction of CD44 expression on both CD4⁺ and CD8⁺ cells. (C) Representative flow plots of intracellular cytokine staining of recipient splenocytes, gated on CD8⁺ T cells. 10⁶ recipient splenocytes were incubated with 2×10⁶ BALB/c stimulator splenocytes for 5 hours and then fixed and permeabilized before being stained for FACS analysis. (D) Frequencies and absolute numbers of cytokine-producing CD8⁺ T cells. Treatment with MR-1, 7E1-G2b or CD154 dAbs results in the reduction of percentage of multicytokine producing CD8⁺ T cells. Data are cumulative of two separate experiments with a total of 8 to 10 mice per group. ** p < 0.01, *** p < 0.001.