TBX21 and multiple system atrophy: Nevertheless, using Tcrb−/− and Cd4−/− mice, we expanded our findings to show that these infiltrating T cells, and more specifically Tbet+, IFN-γ producing Th1 CD4 T cells (Fig. 7), are involved in mediating not only the CNS myeloid response to Olig001 SYN (Fig. 4), but also the demyelination associated with this model of MSA (Fig. 7).