Even though Ag+ CD4 T cells from LD-infected mice exhibited a similar polyfunctional response at 2 wk p.i. (Fig. 5A), the number of Ag+ CD4 T cells that retained the ability to produce both IFN-γ and TNF-α at week 8 p.i. was significantly greater in LD-infected mice as compared with animals that received HD (Fig. 5B). This evidence concerns the gene CD4 and Huntington disease.